CONDITIONING SYSTEM FOR A TEST BENCH

Description

[0001] The invention relates to a mixing unit for a conditioning system of a test bench, for conditioning an operating medium of a test circuit of a test specimen mounted on the test bench to a predetermined target temperature, and to a conditioning unit for a conditioning system of a test bench, for conditioning an operating medium of a test circuit of a test specimen mounted on the test bench to a predetermined target temperature. Furthermore, the invention relates to a conditioning system for a test bench, for conditioning an operating medium of a test circuit of a test specimen mounted on the test bench to a predetermined target temperature, and to a test bench with a test specimen and with a conditioning system for conditioning an operating medium of a test circuit of the test specimen to a predetermined target temperature.Furthermore, the invention relates to a method for conditioning an operating medium of a test specimen circuit of a test specimen on a test bench to a predetermined target temperature.

[0002] Conditioning systems can be used on test benches for certain test experiments in order to condition specific liquid or gaseous operating media of a test object to a desired temperature. For example, entire vehicles, vehicle subsystems, or individual vehicle components are tested as test objects. A vehicle subsystem is, for example, a powertrain, which can comprise one or more components, such as drive units, transmissions, etc. A component can be, for example, a drive unit such as an internal combustion engine, electric motors, combinations of internal combustion engines and electric motors (so-called hybrid drives). However, components can also be, for example, fuel cells, batteries, transmissions, etc. Each test object usually has at least one test object circuit for an operating medium, such as a coolant, fuel, lubricating oil, etc.During operation of the test object on the test bench, the operating medium circulates in the test object circuit, usually involving heat input into the operating medium. It is often desirable to adjust certain temporal temperature profiles of the operating medium in the test object circuit on the test bench as precisely and as quickly as possible. For example, it may be desirable to recreate a temperature profile of an operating medium in the test object previously recorded under real conditions (e.g., in a real vehicle while driving a specific route) on the test bench, or even a simultaneously simulated temperature profile. It may also be desirable to keep the temperature as constant as possible.In particular, rapid temperature changes of the operating medium on the test bench by means of a conditioning system can only be inadequately controlled to date, which is essentially due to the relatively high thermal inertia of the operating media used.

[0003] Conditioning systems and components of conditioning systems are known, for example, from WO 2019 / 183658 A1, WO 2019 / 149792 A1, EP 3 293 504 A1, DE 10 2009 013449 A1 or from US 2019 / 091641 A1.

[0004] It is therefore the object of the invention to provide a device and a method which make it possible to condition an operating medium in a test circuit of a test specimen on a test bench to a desired temperature as quickly as possible.

[0005] According to the invention, the object is achieved with a conditioning unit in that at least one mixing unit inlet connection and at least one mixing unit outlet connection are provided on the conditioning unit for connecting the conditioning unit to a mixing unit that can be fluidically integrated into the test specimen circuit, wherein the at least one mixing unit inlet connection and the at least one mixing unit outlet connection are fluidically connected within the conditioning unit to form part of a conditioning circuit for the operating medium, wherein a main flow line of the conditioning circuit connected to the at least one mixing unit inlet connection is divided into at least two partial flow lines in the conditioning unit, wherein each partial flow line is connected to the at least one mixing unit outlet connection,The operating medium in one partial flow line can be conditioned to a predetermined conditioning temperature, and the at least one further partial flow line can be flowed through by unconditioned operating medium with a neutral temperature that is higher or lower than the conditioning temperature. The flow rate of the operating medium in the at least two partial flow lines can be adjusted depending on the predetermined target temperature in the test sample circuit. By adjusting the flow rate, a specific mixing ratio of operating medium from the at least two partial flow lines can be generated depending on the predetermined target temperature, so that the target temperature can be reached as quickly as possible.

[0006] Advantageous embodiments of the conditioning unit are specified in the dependent claims 2 to 11.

[0007] Furthermore, the object is achieved by a method in that a mixing unit is fluidically integrated into the test specimen circuit in order to form a part of the test specimen circuit, wherein operating medium of the test specimen circuit to be conditioned is supplied to the mixing unit via at least one test specimen circuit inlet connection and operating medium conditioned to the predetermined target temperature is discharged from the mixing unit via at least one test specimen circuit outlet connection, wherein at least operating medium with a predetermined conditioning temperature and operating medium with a relatively higher or lower neutral temperature is supplied to the mixing unit via at least one conditioning unit inlet connection,which is mixed with the supplied operating medium of the test specimen circuit in a mixing area provided within the mixing unit and is discharged from the mixing unit via at least one conditioning unit return connection, wherein a flow of the operating medium with the conditioning temperature and a flow of the operating medium with the neutral temperature are set depending on the specified target temperature.

[0008] Advantageous embodiments of the method are specified in dependent claims 13 to 16.

[0009] The object can further be achieved advantageously with a mixing unit in that a mixing area is provided in the mixing unit, in which the operating medium of the test specimen circuit can be mixed with preconditioned operating medium from a conditioning circuit in order to condition the operating medium in the test specimen circuit to the predetermined target temperature, wherein at least one test specimen circuit inlet connection and at least one test specimen circuit outlet connection are provided on the mixing unit for the fluidic integration of the mixing unit into the test specimen circuit, which are fluidically connected to one another via the mixing area in order to form part of the test specimen circuit, wherein at least one conditioning unit inlet connection and at least one conditioning unit return connection are provided on the mixing unit for connecting the mixing unit to a conditioning unit of the conditioning system,which are fluidically connected to each other via the mixing area to form part of the conditioning circuit for the operating medium. This allows a very homogeneous mixture to be created and pressure loss in the test sample circuit to be kept as low as possible.

[0010] The present invention is described below with reference to the Figuren 1a bis 7 which show exemplary, schematic and non-limiting advantageous embodiments of the invention. Fig.1a a conditioning system of the invention in an advantageous embodiment, Fig.1b a conditioning system of the invention in an alternative embodiment Fig.2 a mixing unit in an advantageous embodiment, Fig.3 a flow pattern in the mixing chamber of the mixing unit, Fig.4 a mixing unit in an alternative embodiment and Fig.5 a valve unit in an advantageous embodiment, Fig.6 a sectional view of a valve housing of the valve unit and Fig.7 a mixing element of the valve unit.

[0011] Fig.1a shows a schematic representation of a conditioning system 1 according to the invention on a test bench in an advantageous embodiment. The conditioning system 1 has a conditioning unit 2 and a mixing unit 3, which are fluidically connected to one another to form a conditioning circuit KK for a fluid operating medium. A fluid operating medium is understood here to be a suitable gaseous or liquid medium. For example, a coolant, a fuel, an oil, air, etc. can be provided as the operating medium. In the context of the invention, "fluidically connected" is understood to mean a fluid-mechanical connection, for example via suitable pipes, lines, etc. The mixing unit 3 can be fluidically integrated into a test specimen circuit PK of a test specimen P mounted on a test bench, in which the same operating medium circulates.The type of operating medium used in the conditioning circuit KK depends on the operating medium used in the test object circuit PK of the test object P. As mentioned at the beginning, the test object P can be, for example, a transmission such as a manual transmission, automatic transmission or an axle drive, a drive unit such as an internal combustion engine, electric motor, a hybrid drive, an energy storage device such as a battery or an energy converter such as a fuel cell, etc. However, the type of test object P used is irrelevant for the invention. In principle, any test object P with a test object circuit PK with operating medium can be used. If the test object has several operating media, several of such conditioning systems 1 according to the invention can of course also be provided on the test bench. In order to control the test object P on the test bench in accordance with a test experiment, a test bench control unit 21 is generally provided in a known manner.

[0012] In the test sample circuit PK, a pump (not shown) for conveying the operating medium can of course also be provided, which can be part of the test bench or part of the test sample P. Of course, other components such as heat exchangers, valves, sensors, throttles, etc. can also be provided in the test sample circuit PK, which, however, are irrelevant for the invention. The mixing unit 3 can, as in Fig.1 shown, in the flow direction of the operating medium after the test specimen P in the test specimen circuit PK. However, the mixing unit 3 can also be provided in the flow direction of the operating medium before the test specimen P, as in Fig.1 is indicated by the dashed test specimen P.

[0013] The temperature behavior of the operating medium is to be simulated on the test bench with the aid of the conditioning system 1. In particular, the conditioning system 1 according to the invention is to simulate the heat input of the test object P into the test object circuit PK, which heat input results from the operation of the test object P. For this purpose, the test object P can actually be operated as intended on the test bench, so that it itself performs work through which the operating medium in the test object circuit PK is heated. The conditioning system 1 could, for example, be used to simulate a higher or lower heat input from the test object P. However, the test object P can also be used solely to reproduce the pressure loss in the test object circuit PK caused by the test object P as realistically as possible.In this case, the test specimen P is not operated itself, thus it does not cause any heat input into the operating medium of the test specimen circuit PK, but its heat input is emulated by the conditioning system 1 according to the invention.

[0014] For this purpose, preconditioned operating medium from the conditioning circuit KK and the operating medium of the test sample circuit PK are mixed in the mixing unit 3 in such a way that a predetermined target temperature T_SOLL of the operating medium in the test sample circuit PK is set downstream of the mixing unit 3. The preconditioning of the operating medium in the conditioning circuit KK is carried out by the conditioning unit 2, as explained in more detail below. Advantageous embodiments of the mixing unit 3 are described with reference to Fig.2 + Fig.3 as well as Fig.4 described in more detail.

[0015] Generally, at least one mixing unit inlet connection 4 and at least one mixing unit outlet connection 5 are provided on the conditioning unit 2 for connecting the conditioning unit 2 with the mixing unit 3. In the example shown according to Fig.1a For example, three mixing unit outlet connections 5a-5c are provided. The mixing unit inlet connection 4 is fluidically connected to the three mixing unit outlet connections 5a-5c within the conditioning unit 2 to form part of the conditioning circuit KK for the operating medium. Generally, a main flow line 6 of the conditioning circuit KK connected to the mixing unit inlet connection 4 is divided within the conditioning unit 2 into at least two partial flow lines 7a+7c (or 7b+7c), for example, at a distribution node 8.

[0016] In general, the operating medium in one of the at least two partial flow lines 7a, 7b can be conditioned to a predetermined conditioning temperature T1, T2, and the at least one further partial flow line 7c can be flowed through by unconditioned operating medium with a neutral temperature T3 that is higher or lower than the conditioning temperature T1, T2. The embodiment with a conditioning temperature T1 that is higher than the neutral temperature T3 can be used if only heating of the operating medium in the test object circuit PK is desired. The embodiment with a conditioning temperature T2 that is lower than the neutral temperature T3 can be used if cooling of the operating medium in the test object circuit PK is desired.For conditioning to the conditioning temperature T1, T2 which is higher or lower relative to the neutral temperature T3, a suitable temperature control unit 9a, 9b can be provided in the respective partial flow line 7a, 7b, as will be explained in more detail below.

[0017] In the example shown in Fig.1a The main flow line 6 is divided within the conditioning unit 2 into three partial flow lines 7a, 7b, 7c, thus allowing the operating medium to be heated in the first partial flow line 7a and cooled in the second partial flow line 7b. A preferably controllable pump 15 for conveying the operating medium in the conditioning circuit KK can be provided in the main flow line 6, but a pump (not shown) can also be provided in each of the partial flow lines 7a-7c. Furthermore, a bypass line 16 for the operating medium can also be provided, which connects the main flow line 6 upstream of the pump 15 with the main flow line 6 downstream of the pump in order to bypass the pump 15.A controllable valve 17 can be provided in the bypass line 16 in order to reduce, preferably completely compensate, a pressure loss Δp in the test specimen circuit PK caused by the mixing unit 3, as will be explained below with reference to the example shown in . Fig.2-Fig.4 As an alternative or in addition to the bypass line 16 including valve 17, a throttle point 29 with an adjustable orifice plate can also be provided in the mixing unit 3, via which the pressure loss can be compensated, as can also be seen from Fig.2-Fig.4 will be explained in more detail.

[0018] In the example according to Fig.1a Each partial flow line 7a-7c within the conditioning unit 2 is connected to a mixing unit outlet connection 5a-5c. The mixing unit outlet connections 5a-5c can in turn be connected, for example, via supply lines ZLa-Zlc, to the mixing unit 3 in order to supply the preconditioned operating medium to the mixing unit 3. The operating medium can be conditioned to a first conditioning temperature T1 in a first partial flow line 7a and to a second conditioning temperature T2 in a second partial flow line 7b. The operating medium can flow through a third partial flow line 7c at a neutral temperature T3 lying between the first and second temperatures and is preferably not conditioned separately. The temperature ranges of the conditioning temperatures T1, T2 depend essentially on the specified boundary conditions or requirements for the conditioning system 1, such as, for example,from a minimum or maximum required target temperature T_TARGET of the operating medium and / or the operating medium used. The neutral temperature T3, which lies between the conditioning temperatures T1 and T2, depends essentially on the temperature of the operating medium flowing back from the mixing unit 3.

[0019] Preferably, at least one first temperature control unit 9a is provided in the first partial flow line 7a of the conditioning unit 2 in order to condition the operating medium to the first (high) conditioning temperature T1. Likewise, at least one second temperature control unit 9b is preferably provided in the second partial flow line 7b in order to condition the operating medium to the second (low) conditioning temperature T2. In principle, all devices suitable for conditioning the operating medium in the first and second partial flow lines 7a, 7b to the respectively provided conditioning temperatures T1, T2 can be used as the temperature control unit 9a, 9b, such as heat exchangers, (e.g., electric) heating devices, cooling devices, heat pumps, Peltier elements, etc.For example, at least one heat source supply connection 10a and at least one heat source return connection 10b for connecting a heat source can be provided on the conditioning unit 2. The heat source supply connection 10a and the heat source return connection 10b can be fluidically connected to the first temperature control unit 9a, which is designed as a heat exchanger, to form part of a heat source supply circuit VK1.

[0020] In an analogous manner, at least one heat sink flow connection 11a and at least one heat sink return connection 11b for connecting the heat sink can also be provided on the conditioning unit 2, which are fluidically connected to the second temperature control unit 9b designed as a heat exchanger in order to form part of a heat sink supply circuit VK2. Essentially any suitable device can be used as the heat source, with which the supply medium of the heat source supply circuit VK1 is kept at a relatively high supply temperature that is as constant as possible, for example in the range of 10K above the max. required target temperature. Analogously, essentially any suitable device can be used as the heat sink, with which the supply medium of the heat sink supply circuit VK2 is kept at a relatively low supply temperature that is as constant as possible, for example in the range of 10K below the min.required target temperature. The supply medium can be, for example, the operating medium or another suitable medium.

[0021] The heat supply by the heat source and heat sink can, for example, take place in a separate supply module 12, which forms a self-sufficient unit to which the conditioning unit 2 can be connected. Of course, further (not shown) hydraulic components for the supply circuits VK1, VK2 can also be provided in the supply module 12, for example pumps, pressure control devices, valves, tanks, etc. The control of the supply module 12 could, for example, be carried out by a conditioning unit control unit 20, which can, for example, be arranged in the conditioning unit 2. However, the control of the supply module 12 could, for example, also be carried out by a test bench control unit 21 of the test bench on which the conditioning system 1 is used (as indicated by the dashed connecting line in Fig.1 is indicated).

[0022] However, test benches often have a central media supply system, for example, as part of the test bench building, for the provision of preconditioned supply media. For example, several, even different, test benches can be supplied with one or more preconditioned supply media via the central media supply system. The provision of the preconditioned supply media for the supply circuits VK1, VK2 of the first and second temperature control units 9a, 9b, in particular heat exchangers, could in this case be provided, for example, via supply lines L1, L2 of the central media supply system, as shown in Fig.1a is indicated. In this case, a separate supply module 12 is not necessary.

[0023] The conditioning unit 2 is designed to control, in particular to regulate, a flow of the operating medium, e.g. volume flow or mass flow, in the three partial flow lines 7a-7c (or generally at least two partial flow lines 7a+7c or 7b+7c) depending on the predetermined target temperature T_SOLL of the operating medium in the test piece circuit PK, so that the target temperature T_SOLL in the test piece circuit PK can be set as quickly as possible. For this purpose, the preconditioned operating medium from the partial flow lines 7a-7c of the conditioning unit 2 is mixed with the operating medium in the test piece circuit PK depending on the predetermined target temperature T_SOLL test piece circuit PK, wherein the mixing takes place in the mixing unit 3, in particular in a mixing area 28 of the mixing unit 3, as described below with reference to Fig.2-Fig.4 will be explained in more detail below. In order to form the conditioning circuit KK, the conditioning unit 2 can be connected to the mixing unit 3, for example, via one or more suitable supply lines ZLa-ZLc and one or more suitable return lines RL.

[0024] For this purpose, at least one conditioning unit inlet connection 27a and one conditioning unit return connection 27b are provided on the mixing unit 3. The conditioning unit return connection 27b can be connected via the return line RL to the mixing unit inlet connection 4 of the conditioning unit 2. In the example shown in Fig.1a A supply line ZLa-ZLc is connected to each mixing unit outlet connection 5a-5c of the conditioning unit 2. If a single conditioning unit supply connection 27a is provided on the mixing unit 3, the supply lines ZLa-ZLc can preferably be combined into a common collecting line SL immediately upstream of the mixing unit 3, as shown in Fig.1a is indicated. The common collecting line SL can then be connected to the conditioning unit inlet connection 27a. However, a plurality of (not shown) conditioning unit inlet connections 27a could also be provided on the mixing unit 3, for example three conditioning unit inlet connections 27a (or one conditioning unit inlet connection 27a per inlet line ZLa-ZLc). In this case, each mixing unit outlet connection 5a-5c could be connected to a conditioning unit inlet connection via an inlet line ZLa-ZLc. The plurality of conditioning unit inlet connections 27a could then be combined in the mixing unit 3 to form a collecting line SL, which in turn opens into the mixing area 28 of the mixing unit 3.In order to quickly reach the desired target temperature T_SOLL in the test specimen circuit PK, it is advantageous if the preconditioned operating medium is only brought together into a stream in the collecting line SL as close as possible to the mixing unit 3, preferably only directly in the mixing unit 3.

[0025] The flow rates in the three partial flow lines 7a-7c of the conditioning unit 2 (or generally at least two partial flow lines 7a+7c or 7b+7c) can be set as a function of the desired target temperature T_SOLL to be achieved in such a way that a preconditioned mixture of operating medium of the first conditioning temperature T1 or operating medium of the second conditioning temperature T2 and operating medium of the intermediate neutral temperature T3 is formed in the conditioning circuit KK with a specific mixing ratio, so that when this preconditioned mixture of the operating medium from the conditioning circuit KK is mixed with the operating medium of the test object circuit PK, the specified target temperature T_SOLL in the test object circuit PK is established as quickly as possible.The conditioning temperatures T1, T2 and the neutral temperature T3 of the operating medium in the partial flow lines 7a, 7c are essentially constant, and the target temperature T_TARGET is essentially set only by controlling or regulating the flows in the partial flow lines 7a-7c of the conditioning unit 2, so that a specific mixing ratio is achieved. If only two partial flow lines (warm + neutral or cold + neutral) are provided, naturally only these two partial flows are mixed with a specific mixing ratio, so that the target temperature T_TARGET is set in the test specimen circuit PK. The flow in the conditioning circuit KK is preferably higher than the flow in the test specimen circuit PK, so that the operating medium in the test specimen circuit PK is preferably essentially completely replaced by the preconditioned operating medium from the conditioning circuit KK.

[0026] To control the flow rates, a known pressure control unit 13a, 13b can be provided, for example, in the first partial flow line 7a and in the second partial flow line 7b of the conditioning circuit KK of the conditioning unit 2, and a check valve 14 can be provided in the third partial flow line 7c. In the main flow line 6, for example upstream of the distribution node 8, a first measuring orifice 18 with a differential pressure sensor 18a for measuring a differential pressure Δp1 across the first measuring orifice 18 can be provided, and in the third partial flow line 7c, for example downstream of the distribution node 8, a second measuring orifice 19 with a differential pressure sensor 19a for measuring a differential pressure Δp2 across the second measuring orifice 19 can be provided.Since the differential pressures Δp1, Δp2 are proportional to the square of the respective flow rate (volume flow, mass flow), the percentage flows (= partial volume flows, partial mass flows) in the partial flow lines 7a-7c can be calculated from the difference between the measured differential pressures Δp1, Δp2. With a difference of Δp1- Δp2=0, for example, 100% of the operating medium flows through the third partial flow line 7c, with a difference of Δp1- Δp2= 0.5 × Δp1, for example, 75% of the operating medium flows through the third partial flow line 7c and 25% through the first or the second partial flow line 7a, 7b (or generally through the at least one partial flow line 7a or 7b), etc. Alternatively, instead of the measuring orifice 18 with differential pressure sensor 18a and the measuring orifice 19 with differential pressure sensor 19a, a suitable (not shown) flow measuring unit can be provided, with which the flow (volume flow, mass flow) can be measured directly, e.g.in the form of a well-known MID sensor (magnetic inductive flow meter) or a Coriolis mass flow meter.

[0027] The conditioning system 1 can be controlled, for example, via a suitable control unit in the form of hardware (microprocessor-based hardware, integrated circuit (such as an ASIC, FPGA), programmable logic controller, analog circuit, or a combination of such hardware) and / or software. For example, the control could be carried out directly via a higher-level control unit, such as the test bench control unit 21 of the test bench, which is usually present on every test bench anyway. The test object P and any other devices of the test bench are usually controlled or regulated via the test bench control unit 21, e.g. a loading machine (not shown) for driving or loading the test object P and / or a supply module 12, etc. Alternatively or additionally, a conditioning unit control unit 20 could also be provided in the conditioning unit 2.The test bench control unit 21 could then communicate in a suitable manner with the conditioning unit control unit 20 to exchange control information. For example, the test bench control unit 21 could be connected to the conditioning unit 2 via a suitable test bench interface S, via which control data can be transmitted or exchanged.

[0028] One or more suitable controllers, for example PID controllers, can be provided in the test bench control unit 21 and / or the conditioning unit control unit 20 in order to regulate a predetermined setpoint value X_ACTUAL in the test object circuit PK, in particular the setpoint temperature T_SETPOINT. Optionally, however, a setpoint pressure loss Δp_SETPOINT could also be regulated across the mixing unit 3, in particular in order to be able to compensate for the design-related pressure loss of the mixing unit 3 or to simulate various pressure losses. A known feedforward control can advantageously also be implemented in the control system, so that the controller only has to correct for minor errors. The setpoint values ​​X_SETPOINT of the control system can be specified, for example, via the test bench control unit 21. For example, a simulation unit 22 in which a simulation model is implemented can also be provided in the test bench control unit 21.With the simulation model 22, for example, a specific temporal progression of a target value X_SOLL, in particular a temporal progression of a target temperature T_SOLL, can be generated. However, a measured temporal temperature progression could also be used as the target temperature T_SOLL, for example, which originates from a real test drive with a vehicle, for example, from a vehicle in which the test object P to be examined was installed or from test bench tests already conducted with the test object P, etc.

[0029] In the simplest case, a constant setpoint X_SOLL, e.g., a constant setpoint temperature T_SOLL and / or a constant pressure loss Δp_SOLL, could of course also be specified, for example, by manual input via a suitable input device such as a computer. The setpoints X_SOLL can, for example, be transferred from the test bench control unit 21 via the test bench interface S to the conditioning unit control unit 20 and processed by the latter. From the specified setpoint(s) X_SOLL and from the recorded actual values ​​X_IST, the conditioning unit control unit 20, for example, the controller implemented therein, determines the required manipulated variables X_STELL of the actuators required for the control, for example, the pressure control units 13a, 13b ( Fig.1a ) and / or the pump 15 and / or the controllable valve 17 in the bypass line 16 and / or a valve unit 34 ( Fig.1b ) and / or an actuator A of an adjustable orifice of the throttle point 29 ( Fig.1b ).

[0030] Actual values ​​X_IST of the control system can be recorded during operation of the conditioning system 1 by suitable sensors, e.g. at the conditioning unit 2 and the mixing unit 3, and transmitted to the conditioning unit control unit 20. In the conditioning unit 2 and the mixing unit 3, for example, one or more temperature sensors 23, pressure sensors 24 and differential pressure sensors 24a, 18a, 19a can be provided, with which an actual temperature T _IST, an actual pressure p_IST or an actual differential pressure Δp_IST of the operating medium (or the supply medium of the temperature control units 9a, 9b designed as heat exchangers) can be determined. In the mixing unit 3, for example, a differential pressure sensor 24a can be provided in order to record the pressure loss Δp_IST across the mixing unit 3.As is well known, a differential pressure sensor 24a can also be understood as two individual pressure sensors 24, each generating a measured value. The pressure loss Δp_ACTUAL can then be determined from the difference between the measured values ​​of the pressure sensors 24. The same applies analogously to the differential pressure sensors 18a, 19a.

[0031] The aforementioned pressure control units 13a, 13b of the first and second partial flow lines 7a, 7b can be provided as actuators for regulating the temperature in the operating medium of the test specimen circuit PK. The flow rate in the at least two partial flow lines 7a+7c or 7b+7c can be adjusted via the pressure control units 13a, 13b depending on the target temperature T_SOLL. The control unit 21, 20 can, for example, determine a target differential pressure Δp2_SOLL in the third partial flow line 7c based on the general Richmann mixing rule according to the relationship Δ p 2 _ SOLL = Δ p 1 * T _ SOLL − T 3 Tx − T 3 2 calculate. Where Δp1 is the differential pressure measured by means of orifice plate 18 in the main flow line 6 upstream of junction 8, T_SOLL is the desired setpoint temperature of the operating medium, T3 is the neutral temperature of the operating medium in the third partial flow line 7c and Tx represents the conditioning temperature T1 or T2 of the operating medium in the first or second partial flow line 7a, 7b. From the setpoint differential pressure Δp2_SOLL and the actual differential pressure Δp2_IST measured by means of orifice plate 19, the control unit 20, 21 can use a suitable controller, e.g. a PI or PID controller, to determine a manipulated variable X_STELL, with which the pressure control units 13a, 13b are controlled.If, for example, suitable flow measuring devices are used to measure the mass flow or volume flow instead of the measuring orifices 18, 19 with differential pressure sensors 18a, 19a, Richmann's mixing rule could of course also be used in an analogous manner to calculate a target mass flow or a target volume flow.

[0032] The above relationship can also be used, for example, to determine an actual temperature T _IST of the mixed operating medium, e.g. in the area of ​​the collecting line SL in the mixing unit 3, at which Fig.1a the temperature sensor 23 is shown. This can be particularly advantageous in the dynamic operation of the conditioning system 1, in which, for example, a time-varying temperature profile of the target temperature T_SOLL in the test sample circuit PK is to be set, because the temperature sensor 23 may not be able to detect rapid temperature changes quickly enough. The actual temperature T_IST of the mixture can, for example, be determined using the general Richmann mixing rule according to T _ IST = mx * Tx + m 3 * T 3 mx + m 3 calculated. Where mx stands for the mass flow m1, m2 of the operating medium in the first or second partial flow line 7a, 7b, Tx stands for the conditioning temperature T1, T2 in the first or second partial flow line 7a, 7b, m3 stands for the mass flow in the third partial flow line 7c and T3 stands for the neutral temperature in the third partial flow line 7c. The prerequisite for this is that the mass flows mx, m3 are known. For this purpose, for example, suitable flow measuring devices for measuring the mass flow mx, m3 can be used instead of the orifices 18, 19. If suitable flow measuring devices for measuring the volume flow are provided instead of the orifices 18, 19, the volume flows could of course also be used for the calculation.

[0033] For flow measurement using the Fig.1a (and subsequently also in Fig.1b ) shown measuring orifices 18, 19 with differential pressure sensors 18a, 19a, the following relationship results: T _ IST = Δ p 2 Δ p 1 * Tx − T 3 + T 3 .

[0034] For example, the controllable valve 17 in the bypass line 16 of the pump 15 can be used as an actuator for regulating or compensating the pressure loss in the mixing unit 3. Alternatively or in addition to the control via the valve 17, the pressure loss compensation can also be carried out by varying the delivery rate of the pump 15 (e.g., by varying the pump speed). Furthermore, an adjustable orifice plate could also be provided in the mixing unit 3 to regulate the pressure loss ( Fig.1b ). Depending on the specified setpoints X_SOLL, the conditioning unit control unit 20 can calculate corresponding manipulated variables X_STELL and adjust them via the actuators.

[0035] In Fig.1b An alternative embodiment of the conditioning system 1 is shown. The structure and function of the conditioning system 1 essentially correspond to the conditioning system 1 from Fig.1a , which is why only the main differences are discussed below. In contrast to Fig.1a Only one mixing unit outlet connection 5 is provided on the conditioning unit 2. The partial flow lines 7a-7c (or generally the at least two partial flow lines 7a+7c or 7b+7c) are therefore already combined within the conditioning unit 2 to form a conditioning unit collecting line KSL, which is connected to the mixing unit outlet connection 5. Consequently, only a single inlet line ZL is required to connect the mixing unit 3 to the conditioning unit 2. This requires fewer lines, allowing for a simpler connection.

[0036] In the conditioning unit 2, a valve unit 34 can be provided for mixing the operating medium from the three partial flow lines 7a-7c (or generally at least two partial flow lines 7a+7c; 7b+7c) and for supplying it to the conditioning unit collecting line KSL. The partial flow lines 7a-7c are connected to the conditioning unit collecting line KSL via the valve unit 34, and the conditioning unit collecting line KSL is in turn connected to the mixing unit drain connection 5. Alternatively or additionally, a valve unit 34 (not shown) could also be provided at the junction 8 for distributing the operating medium from the main flow line 6 to the partial flow lines 7a-7c, wherein the main flow line 6 is connected to the partial flow lines 7a-7c via the valve unit 34.By using a controllable valve unit 34, the pressure control units 13a, 13b in the partial flow lines 7a, 7b and the check valve 14 in the third partial flow line 7c can be dispensed with, as shown in . Fig.1b An advantageous embodiment of the valve unit 34 is described below with reference to Fig.5 explained in more detail.

[0037] In the mixing unit 3 shown in Fig.1b is in contrast to Fig.1a An adjustable orifice plate is provided at the throttle point 29, which can be adjusted by an electrically controllable actuator A, for example a suitable actuator, in order to change the flow cross-section of the throttle point 29. This allows the bypass line 16 and the controllable valve 27 to be Fig.1a omitted and the pressure loss compensation can be carried out by adjusting the orifice by means of the actuator A. For this purpose, a differential pressure sensor 24a for measuring a differential pressure Δp as the actual value X_IST can be provided in the mixing unit 3. The actual value X_IST can be transmitted, for example, to the test bench control unit 21 and / or to the conditioning unit control unit 20, which determines a manipulated variable X_STELL, which is transmitted to the actuator A, as in Fig.1b is indicated. If the pressure loss compensation is carried out only via the orifice plate, in a simple embodiment, for example, a controllable pump 15 could be dispensed with and a pump 15 with a constant flow rate could be used in the conditioning unit 2.

[0038] The following is based on reference to Fig.2 bis Fig.4 The mixing unit 3 is explained in more detail using two advantageous embodiments. Fig.2 the mixing unit 3 of a first embodiment in a perspective view and Fig.3 a flow pattern of the operating medium within the mixing unit 3 Fig.2 in top view. Fig.4 shows a mixing unit 3 in an alternative embodiment in a perspective view. In general, the mixing unit 3 can have a housing 25 made of a suitable material, for example a steel or aluminum alloy or plastic, in which suitable flow channels are provided for guiding the operating medium. On the mixing unit 3, at least one test specimen circuit inlet connection 26a and at least one test specimen circuit outlet connection 26b are provided for fluidic integration of the mixing unit 3 into the test specimen circuit PK of the test specimen P. As a result, the mixing unit 3 can be easily integrated into an existing test specimen circuit PK of a test specimen P on the test bench, without any structural changes to the test bench being necessary.

[0039] Of course, connecting and sealing elements not shown can also be provided on the mixing unit 3 in order to enable the simplest and leak-free connection possible, e.g. of a pipe or a hose of the test sample circuit PK to the test sample circuit inlet connection 26a and the test sample circuit outlet connection 26b of the mixing unit 3. The test sample circuit inlet connection 26a and the test sample circuit outlet connection 26b are fluidically connected within the mixing unit 3 via the mixing area 28 to form part of the test sample circuit PK. Operating medium can thus flow within the mixing unit 3 from the test sample circuit inlet connection 26a via the mixing area 28 to the test sample circuit outlet connection 26b, as shown in Fig.2-Fig.4 indicated by the two arrows and as in Fig.3 can be seen from the flow. Within the scope of the invention, the mixing area 28 is understood to mean the entire area within the mixing unit 3 in which the operating medium from the conditioning circuit KK and the operating medium from the test sample circuit PK are in contact.

[0040] As described, at least one conditioning unit inlet connection 27a and at least one conditioning unit return connection 27b are provided on the mixing unit 3 for connecting the mixing unit 3 to the conditioning unit 2 of the conditioning system 1. As mentioned, the connection can be made, for example, via a return line RL and one or more inlet lines ZL, ZLa-ZLc, for example, one inlet line ZLi per partial flow line ( Fig.1a ) or a common supply line ZL ( Fig.1b ). If there are multiple inlet lines ZLa-ZLc, these can be combined upstream of the mixing unit 3 to form a common collecting line SL, or multiple conditioning unit inlet connections 27a could be provided, each of which can be connected to a supply line ZLa-ZLc. The preconditioned operating medium from the partial streams can be combined into one stream via a collecting line SL in the mixing unit 3.

[0041] The at least one conditioning unit inlet connection 27a and the at least one conditioning unit return connection 27b are also fluidically connected within the mixing unit 3 via the mixing area 28 in order to form part of the conditioning circuit KK (see Fig.1a , 1b) for the operating medium. As a result, the preconditioned operating medium, which is supplied to the mixing unit 3 from the conditioning unit 2, can flow within the mixing unit 3 from the conditioning unit inlet connection 27a via the mixing area 28 to the conditioning unit return connection 27b, as shown in Fig.2 is indicated by the two arrows. The flow of the operating medium in the conditioning circuit KK is thus opposite to the flow of the operating medium in the test specimen circuit PK, which ensures good mixing. In addition, the pressure loss in the test specimen circuit PK can be compensated for via the throttle point 29. Of course, connecting and sealing elements (not shown) can be provided on the mixing unit 3 in order to enable the most leak-free connection possible, for example of a pipe or a hose in the conditioning circuit KK, to the conditioning unit inlet connection 27a and the conditioning unit outlet connection 27b of the mixing unit 3.

[0042] As mentioned, a mixing area 28 is provided in the mixing unit 3, in which the operating medium of the test sample circuit PK can be mixed with the conditioned operating medium from the conditioning circuit KK in order to condition the operating medium in the test sample circuit PK to the specified target temperature. In order to produce as quickly as possible a homogeneous mixture of the operating medium of the conditioning circuit KK and the operating medium of the test sample circuit PK, the mixing area 28 preferably has at least one substantially annular mixing chamber 28a, as shown in particular in Fig.3 can be seen. In general, the term "annular" within the scope of the invention essentially refers to any desired ring shape, for example a cylindrical ring, torus, etc. The conditioning unit return connection 27b is preferably arranged on the mixing unit 3 such that it opens into the mixing region 28 between the test piece circuit inlet connection 26a and the conditioning unit inlet connection 27a.

[0043] In the example according to Fig.2 + Fig.3 For example, the conditioning unit return connection 27b opens into the mixing area 28 between the test circuit inlet connection 26a and the annular mixing chamber 28a. In addition, a throttle point 29 can be provided between the conditioning unit inlet connection 27a and the conditioning unit return connection 27b. In the example according to Fig.2 + Fig.3 the throttle point 29 is arranged, for example, between the annular mixing chamber 28a and the conditioning unit return connection 27b and is designed as a fixed constriction with an unchangeable flow cross-section. The throttle point 29 can generate a differential pressure in the flow of the operating medium between the conditioning unit inlet connection 27a and the conditioning unit return connection 27b, which counteracts the differential pressure in the flow of the operating medium in the test specimen circuit PK. By setting a higher flow rate (volume flow or mass flow) of the operating medium in the conditioning circuit KK relative to the flow rate (volume flow or mass flow) in the test specimen circuit PK (e.g. via a preferably controllable pump 15 and / or bypass line 16 with valve 17), the pressure loss generated by the mixing unit 3 in the test specimen circuit PK can thus be reduced orpreferably fully compensated or set to a specific value. In general, the flow rate (volume flow or mass flow) in the conditioning circuit KK is preferably higher than the flow rate (volume flow or mass flow) in the test specimen circuit PK, for example 5-20%, in particular approx. 10% higher. As a result, the operating medium of the test specimen circuit PK in the mixing unit 3 can advantageously be essentially completely exchanged and replaced by conditioned operating medium from the conditioning circuit KK. The temperature of the operating medium in the region of the at least one conditioning unit inlet connection 27a (e.g. in the collecting line SL - . Fig.1a or in the supply line ZL - Fig.1b ) therefore preferably corresponds substantially to the temperature of the operating medium in the region of the test circuit outlet connection 26b. Therefore, within the scope of the invention, the temperature in the region of at least one conditioning unit inlet connection 27a can also be used as the target temperature T_SOLL and the actual temperature T_IST.

[0044] To control the pressure loss compensation, according to an advantageous embodiment, the flow cross-section at the throttle point 29 can also be variable (alternatively or in addition to controlling the flow in the conditioning circuit KK in the conditioning unit 2). As already mentioned, an adjustable orifice plate can be provided for this purpose, by means of which the flow cross-section of the throttle point 29 can be changed. In the simplest case, the adjustable orifice plate could be manually adjustable, but preferably an electrically controllable actuator A (see Fig.1b ) for adjusting the orifice, which can be controlled, for example, by the conditioning unit control unit 20 and / or by the test bench control unit 21. The control or regulation of the flow of the operating medium of the conditioning circuit KK can, as mentioned, be carried out via a control unit (e.g., test bench control unit 21 or conditioning unit control unit 20). For example, a suitable controller (e.g., PID controller) can be implemented in the conditioning unit control unit 20. The controller can be derived from the signal applied to the mixing unit 3 by means of the differential pressure sensor 24a ( Fig.1 ) measured actual differential pressure Δp_IST in the test specimen circuit PK and a specified target differential pressure Δp_SOLL (e.g., Δp_SOLL = 0), a manipulated variable X_STELL is calculated for the controllable valve 17 in the bypass line 16 of the pump 15 of the conditioning unit 2 and the valve is controlled accordingly. As already mentioned, a known pre-control of the manipulated variable X_STELL can also be implemented in the control system. However, the flow could also be controlled, for example, via a pump 15 with a variable delivery rate, e.g., via a pump 15 with an adjustable pump speed. The control of the adjustable orifice for adjusting the flow cross-section could, for example, also be controlled via a separate control unit and / or via the test bench control unit 21 or the conditioning unit control unit 20.If the adjustable orifice at the throttle point 29 is closed, the pump 15 of the conditioning unit 2 can also be used, for example, to pump the operating medium in the test sample circuit PK. In this case, a separate pump in the test sample circuit PK could also be dispensed with.

[0045] To reduce the pressure loss Δp in the test sample circuit PK, it is advantageous if an inlet opening 30 of the test sample circuit inlet connection 26a, which opens from the radial outside into the annular mixing chamber 28a, and an outlet opening 31 of the test sample circuit outlet connection 26b, which opens from the radial outside into the annular mixing chamber 28a, are spaced apart from one another in the mixing chamber 28a at a circumferential distance of at least 90°, preferably 180°±30°. Furthermore, it can be advantageous if the at least one conditioning unit inlet connection 27a extends into a central region 32 of the mixing unit 3 and opens from the radial inside into the annular mixing chamber 28a, preferably in the region of the inlet opening 30 of the test sample circuit inlet connection 26a. As already shown in Fig.1 As described above, at least one temperature sensor 23 for measuring the actual temperature T_IST of the operating medium can be provided on the mixing unit 3. Preferably, one temperature sensor 23 is provided in the area of ​​the conditioning unit inlet connection 27a, one temperature sensor 23 in the area of ​​the test circuit inlet connection 26a, and one temperature sensor 23 in the area of ​​the test circuit outlet connection 26b, as shown in Fig.3 is indicated. The recorded actual temperatures T_ACTUAL can be transferred, for example, to a control unit (e.g. test bench control unit 21 or conditioning unit control unit 20) for adjusting the target temperature T_SOLL in the test specimen circuit PK.

[0046] In Fig.4 An alternative embodiment of the mixing unit 3 is shown. At least one test sample circuit inlet connection 26a, at least one test sample circuit outlet connection 26b, at least one conditioning unit inlet connection 27a and at least one conditioning unit return connection 27a are provided on the mixing unit 3. In contrast to the variant according to Fig.3 Here, two essentially annular mixing chambers 28a, 28b are provided in the mixing area 28, which preferably communicate radially with each other. In the flow connection between the two annular chambers 28a, 28b, a throttle point 29 is preferably provided. Analogous to that shown in FIG. Fig.3 As described, the throttle point 29 could again have a fixed flow cross-section or an adjustable orifice (not shown) with an actuator A could be provided for adjusting the flow cross-section, as in Fig.1b is indicated. The conditioning unit inlet connection 27a preferably opens substantially centrally in the axial direction into the first mixing chamber 28a, and the test piece circuit outlet connection 26b preferably opens radially into the first mixing chamber 28a. In a similar manner, the conditioning unit return connection 27b preferably opens substantially centrally in the axial direction into the second mixing chamber 28b, and the test piece circuit inlet connection 26a preferably opens radially into the second mixing chamber 28b.In order to keep the pressure loss as low as possible, it is also advantageous here if an inlet opening 30 of the test piece circuit inlet connection 26a opening from the radial outside into the second annular mixing chamber 28b and an outlet opening 31 of the test piece circuit outlet connection 26b opening from the radial outside into the first annular mixing chamber 28a are spaced from one another at an angle of at least 90°, preferably 180°±30°, wherein the inlet opening 30 and the outlet opening 31 are advantageously aligned, as shown.

[0047] In order to achieve the best possible mixing of the preconditioned operating medium from the conditioning circuit KK with the operating medium of the test piece circuit PK, it can also be advantageous if at least one sieve element 33 is provided in the mixing area 28. This can create turbulence in the flow, which improves mixing. With appropriate arrangement in the flow path, the at least one sieve element 33 can also serve as a type of dirt filter, so that, for example, deposits or dirt particles from the test piece circuit PK cannot enter the conditioning circuit KK. For this purpose, for example, at least one sieve element 33 with a sufficiently small mesh size can be provided at least in the area of ​​the conditioning unit return connection 27b. In general, various designs can be used as the sieve element 33, for example perforated sheets, wire mesh, metal grids, etc.

[0048] As in Fig.4 As shown, it is particularly advantageous if a preferably annular sieve element 33 is provided in each of the annular mixing chambers 28a, 28b. In the example shown, the sieve elements 33 are designed as essentially cylindrical sleeves, on the outer circumferential surface of which several openings are provided, which connect the outer circumferential surface with the inner circumferential surface. Depending on the number, size and distribution of the openings on the circumference, the mixing and / or filtering properties can be influenced. In the variant according to Fig.4 For example, one preferably cylindrical recess could first be provided for each mixing chamber 28a, 28b, e.g., drilled or milled into the housing 25. The annular sieve elements 33 can then be inserted in a suitable manner. The annular mixing chamber 28a, 28b is thus formed between the inner circumferential surface of the cylindrical opening and the outer circumferential surface of the annular sieve element 33.

[0049] As a result, the preconditioned operating medium can flow from the conditioning circuit KK via the conditioning unit inlet connection 27a essentially in the axial direction into the cylindrical interior of the annular sieve element 33 and through the openings of the annular sieve element 33 in the radial direction into the annular mixing chamber 28a. From the annular mixing chamber 28a, the operating medium can flow further against the flow direction of the test circuit PK through the throttle point 29 into the second annular mixing chamber 28b. From the second annular mixing chamber 28b, the operating medium can flow essentially in the opposite direction to that in the first mixing chamber 28a, initially radially through the openings in the sieve element 33 into the interior of the sieve element 33 and then in the axial direction to the conditioning unit return connection 27b, as indicated by the arrows in Fig.4 is indicated. At the same time, during the described flow of the operating medium of the conditioning circuit KK, the operating medium of the test specimen circuit PK can flow essentially in the opposite direction through the mixing area 28, as indicated by the corresponding arrows.

[0050] In Fig.5 Finally, a valve unit 34 for use in the conditioning unit 2 is shown in an advantageous embodiment. Fig.6 shows a sectional view of the valve housing 34a of the valve unit 34 from Fig.5. Fig.7 shows a mixing element 37 of the valve unit 34 from Fig.5 As already described, the valve unit 34 can be used to distribute a main fluid flow HS of a (liquid or gaseous) operating medium to at least two partial fluid flows TS and / or to mix at least two partial fluid flows of an operating medium or several different operating media into a main fluid flow HS. The valve unit 34 can therefore advantageously be used, for example, in the Fig.1b The conditioning unit 2 shown can be used to combine the three partial flow lines 7a-7c into a conditioning manifold KSL. Additionally or alternatively, the valve unit 34 could also be used in the conditioning unit 2 at the junction 8 to distribute the main flow line 6 to the three partial flow lines 7a-7c. Independently of the conditioning unit 2, the valve unit 34 could also be provided for other purposes, for example, to generate a mixture of different gases in the main fluid flow HS, which are supplied to the valve unit 34 via the partial fluid flows TS.

[0051] For example, a synthesis gas could be produced from oxygen O2, nitrogen N2 and carbon dioxide CO2.

[0052] The valve unit 34 or the valve housing 34a has at least one main fluid flow connection 36 for the main fluid flow HS and at least one partial fluid flow connection 35a-35c for each partial fluid flow TS, which fluidically communicate via a mixing chamber M provided in the valve unit 34. If the valve unit according to Fig.1b For mixing the partial fluid streams TS of the partial flow lines 7a-7c, for example, the first partial flow line 7a can be connected to the first partial fluid flow connection 35a, the second partial flow line 7b to the second partial fluid flow connection 35b, and the third partial flow line 7c to the third partial fluid flow connection 35c. The conditioning unit collecting line KSL can be connected to the main fluid flow connection 36. A movable mixing element 37 for controlling the flow is provided in the mixing chamber M and can be driven by a drive unit 38. Depending on the position of the mixing element 37, a specific mixing ratio of the partial fluid streams can be set.

[0053] In the example shown, the mixing element 37 is designed, for example, as a rotatable rotor and the drive unit 38 is designed as an electrically actuated actuator, as in Fig.5 The drive unit 38 can be controlled, for example, by a suitable control unit in order to mix the partial fluid streams TS with a specific mixing ratio (or to distribute them in a specific ratio). In the example according to Fig.1b the valve unit 34 can, for example, be controlled by the conditioning unit control unit 20 with a specific manipulated variable X_STELL in order to set a mixing ratio of the operating medium from the partial flow lines 7a-7c so that the desired target temperature T_SOLL is reached in the test specimen circuit PK.

[0054] As in Fig.6 und Fig.7 As can be seen, the mixing chamber M can, for example, be at least partially cylindrical and the mixing element 37 or the rotor can, for example, have a hollow cylinder which is rotatable in the mixing chamber M (see Fig.5 ). On the outer circumferential surface of the hollow cylinder, a control opening 40 is preferably provided, which connects the outer circumferential surface of the hollow cylinder with the inner circumferential surface. The control opening 40 can, for example, be a cylindrical bore, but can also have a different shape. In the example shown, the control opening 40 is designed, for example, as a type of notch. The control opening 40 extends in the circumferential direction over a predetermined area, which essentially depends on the structural design of the valve unit 34, in particular on the relative arrangement of the inlet openings 41a-41c of the partial fluid flow connections 35a-35c into the mixing chamber M, wherein in Fig.6 only the inlet openings 41a, 41c are visible. For example, the control opening 40 can extend over 90-180° in the circumferential direction. In the axial direction, the length of the control opening 40 preferably corresponds to the length of the inlet openings of the partial fluid flow connections 35a-35c. By rotating the rotor or hollow cylinder by means of the drive unit 38, the control opening 40 can be brought at least partially into alignment with at least one inlet opening 41a-41c of the partial fluid flow connections 35a-35c opening into the mixing chamber M. When using the valve unit 34 as a mixing valve (as in Fig.1b ) a specific mixing ratio of the partial fluid flows TS of the operating medium (or the different operating media) in the main fluid flow HS can be set.

[0055] In the example shown according to Fig.5 For example, the rotor can preferably be rotated continuously between a first position in which the control opening 40 communicates exclusively with the inlet opening 41a of the first partial fluid flow connection 35a, a second position in which the control opening 40 communicates exclusively with the inlet opening 41b of the second partial fluid flow connection 35b, and a third position (vertically downwards) in which the control opening 40 communicates exclusively with the inlet opening 41c of the third partial fluid flow connection 35c. In the first position, the inlet openings 41b, 41c of the second and third partial fluid flow connections 35b, 35c are closed, so that 100% of the flow can flow through the first partial fluid flow connection 35a.In the second position, the inlet openings 41a, 41c of the first and third partial fluid flow connections 35a, 35c are closed, so that 100% of the flow flows via the second partial fluid flow connection 35b, and in the third position, the inlet openings 41a, 41b of the first and second partial fluid flow connections 35a, 35b are closed, so that 100% of the flow can flow via the third partial fluid flow connection 35c. When the control opening 40 is positioned between the first and third positions, the first partial fluid flow and the third partial fluid flow are mixed in a specific ratio. When the control opening 40 is positioned between the second and third positions, the second partial fluid flow and the third partial fluid flow are mixed in a specific ratio.The respective mixing ratio depends essentially on the size and geometry of the control opening 40 as well as on the size and geometry of the inlet openings 41a-41c of the partial fluid flow connections 35a-35c.

[0056] At least one swirl recess 39 can preferably also be provided on the outer circumferential surface of the hollow cylinder, which connects the outer circumferential surface of the hollow cylinder with the inner circumferential surface. Preferably, as in Fig.5 und Fig.7 shown, several swirl recesses 39 are provided in the circumferential direction on the hollow cylinder. The swirl recesses 39 are arranged in the axial direction in a section of the hollow cylinder, which is located in the area of ​​an inlet 42 of the main fluid flow connection 36 in the mixing chamber M. This can generate turbulence in the flow, whereby an improved mixing of the partial fluid flows TS can be achieved. When mixing partial fluid flows TS with different temperatures, this can be advantageous, for example, in order to enable the most accurate temperature of the mixture in the main fluid flow HS directly at the valve unit 34, e.g. with the Fig.5indicated temperature sensor 23. As indicated, further temperature sensors 23 can of course also be provided on the valve unit 34, e.g., one temperature sensor 23 for each partial fluid flow connection 35a-35c. To further improve the mixing of the partial fluid flows TS, the recesses 39 can be designed, for example, as elongated holes whose main axes run, for example, parallel to the axis of the hollow cylinder.

[0057] Of course, the valve unit 34 shown is only an example, and other configurations are also conceivable. For example, the mixing chamber M and the mixing element 37 do not have to be cylindrical, but could also have a different shape. Depending on the design of the valve unit 34, in particular the mixing element 37, the mixing chamber M, and the position, size, and geometry of the control opening 40, the mixing behavior of the valve unit 34 can be adapted to specific boundary conditions.

Claims

1. Conditioning unit (2) for a conditioning system (1) of a test bench for conditioning an operating medium of a test object circuit (PK) of a test object (P) mounted on the test bench to a predefined setpoint temperature (T_SOLL), characterized in that at least one mixing unit supply connection (4) and at least one mixing unit outlet connection (5, 5a-5c) are provided on the conditioning unit (2) for connecting the conditioning unit (2) to a mixing unit (3) which can be fluidically integrated into the test object circuit (PK), wherein the at least one mixing unit supply connection (4) and the at least one mixing unit outlet connection (5, 5a-5c) are fluidically connected within the conditioning unit (2) to form a part of a conditioning circuit (KK) for the operating medium, wherein a main flow line (6) of the conditioning circuit (KK) connected to the at least one mixing unit supply connection (4) is divided in the conditioning unit (2) into at least two partial flow lines (7a-7c), wherein each partial flow line (7a-7c) is connected with the at least one mixing unit outlet connection (5, 5a-5c), wherein the operating medium is able to be conditioned in a partial flow line (7a, 7b) to a predefined conditioning temperature (T1, T2), and the at least one further partial flow line (7c) is able to be flowed through by unconditioned operating medium having a relatively higher or lower neutral temperature (T3) compared to the conditioning temperature (T1, T2), wherein a flow rate of the operating medium in the at least two partial flow lines (7a-7c) is able to be adjusted as a function of the predefined setpoint temperature (T_SOLL) in the test object circuit (PK).

2. Conditioning unit (2) according to claim 1, characterized in that the main flow line (6) is divided into at least three partial flow lines (7a-7c), wherein each partial flow line (7a-7c) is connected to the at least one mixing unit outlet connection (5, 5a-5c), wherein the operating medium is able to be conditioned in a first partial flow line (7a) to a first conditioning temperature (T1), is able to be conditioned in a second partial flow line (7b) to a second temperature (T2), and a third partial flow line (7c) is able to be flowed through by unconditioned operating medium having a neutral temperature (T3) lying between the first and second conditioning temperature (T1, T2).

3. Conditioning unit (2) according to claim 1 or 2, characterized in that at least one temperature control unit (9a, 9b), preferably designed as a heat exchanger, is provided in the conditioning unit (2) in at least one partial flow line (7a, 7b) in order to condition the operating medium to the respective conditioning temperature (T1, T2).

4. Conditioning unit (2) according to claim 3, characterized in that at least one heat source supply connection (10a) and at least one heat source return connection (10b) for connecting a heat source are provided on the conditioning unit (2), said heat source connections being fluidically connected to a heat exchanger (9a) arranged in the partial flow line (7a) provided for conditioning the operating medium to the conditioning temperature (T1) that is higher relative to the neutral temperature (T3) in order to form a part of a heat source supply circuit (VK1) and / or that at least one heat sink supply connection (11a) and at least one heat sink return connection (11b) for connecting a heat sink are provided on the conditioning unit (2), said heat sink connections are fluidically connected to a heat exchanger (9b) arranged in the partial flow line (7b) provided for conditioning the operating medium to the lower conditioning temperature (T2) compared to the neutral temperature (T3) in order to form a part of a heat sink supply circuit (VK2).

5. Conditioning unit (2) according to any of claims 1 to 4, characterized in that at least one conditioning unit control unit (20) for controlling at least the flow rate of the operating medium in the at least two partial flow lines (7a-7c) is provided in the conditioning unit (2) and / or in that the conditioning unit (2) can be connected to a test bench control unit (21) via a test bench interface (S) for controlling at least the flow rate of the operating medium in the at least two partial flow lines (7a-7c).

6. Conditioning unit (2) according to any of claims 1 to 5, characterized in that a pressure control unit (13a, 13b) is provided in the at least one partial flow line (7a, 7b) in which the operating medium can be conditioned to the respective conditioning temperature (T1, T2) and that a check valve (14) is provided in the at least one further partial flow line (7c) through which unconditioned operating medium can flow, wherein the at least one pressure control unit (13a, 13b) can be controlled by at least one control unit (20, 21) in order to adjust the flow rate in the at least two partial flow lines (7a-7c).

7. Conditioning unit (2) according to any of claims 1 to 6, characterized in that a first measuring orifice (18) with a differential pressure sensor (18a) for measuring a differential pressure (Δp1) over the first measuring orifice (18) or a flow measuring unit is provided in the main flow line (6) and that a second measuring orifice (19) with a differential pressure sensor (19a) for measuring a differential pressure (Δp2) over the second measuring orifice (19) or a flow measuring unit is provided in the at least one further partial flow line (7c) through which unconditioned operating medium can flow, wherein the control unit (21, 20) is preferably designed to calculate a setpoint differential pressure (Δp2_SOLL) in the third partial flow line (7c) as a function of the specified setpoint temperature (T_SOLL) according to the relationship Δ p 2 _ SOLL = Δ p 1 * T _ SOLL − T 3 Tx − T 3 2 with Tx=T1 orT2 and to calculate a control input variable (X_STELL) for the at least one pressure control unit (13a, 13b) from an actual differential pressure (Δp2_SOLL) measured with the differential pressure sensor (19a) and the setpoint differential pressure (Δp2_SOLL).

8. Conditioning unit (2) according to any of claims 1 to 7, characterized in that in the main flow line (6) a pump (15) for conveying the operating medium in the conditioning circuit (KK) is provided, which pump is preferably controllable by a control unit (20, 21), wherein a bypass line (16) for the operating medium is preferably provided in the conditioning circuit (KK) for bypassing the pump (15), wherein a controllable valve (17) is provided in the bypass line (16), wherein the controllable valve is preferably controllable by a control unit (20, 21).

9. Conditioning unit (2) according to any of claims 1 to 8, characterized in that a controllable valve unit (34) for distributing the operating medium from the main flow line (6) to the at least two partial flow lines (7a-7c) is provided in the conditioning unit (2), wherein the main flow line (6) is connected via the valve unit (34) to the at least two partial flow lines (7a-7c) and / or that a controllable valve unit (34) for mixing the operating medium from the at least two partial flow lines (7a-7c) and supplying to a conditioning unit collecting line (KSL) is provided in the conditioning unit (2), wherein the at least two partial flow lines (7a-7c) are connected to the conditioning unit collecting line (KSL) via the valve unit (34) and the conditioning unit collecting line (KSL) is connected to the at least one mixing unit outlet connection (5).

10. Conditioning unit (2) according to claim 9, characterized in that the valve unit (34) has at least one main fluid flow connection (36) for the main fluid flow (HS) and at least one partial fluid flow connection (35a-35c) per part fluid flow (TS), which fluidically communicate via a mixing space (M), wherein a movable mixing element (37) is provided in the mixing space (M) for preferably continuously controlling a distribution ratio or a mixing ratio of the partial fluid flows (TS), which movable mixing element (37) can be driven by a drive unit (38).

11. Conditioning unit (2) according to claim 10, characterized in that the mixing element (37) is designed as a rotatable rotor and that the drive unit (38) is designed as an electrically operable actuator to rotate the rotor, wherein the rotor preferably has a hollow cylinder, wherein a control opening (40) is provided on the outer circumferential surface of the hollow cylinder, which control opening connects the outer circumferential surface of the hollow cylinder to the inner circumferential surface, wherein the rotor can be rotated, preferably continuously, in order to bring the control opening (40) into an at least partial correspondence with at least one inlet opening of the partial fluid flow connections (35a-35c) which opens into the mixing space (M), wherein at least one turbulence recess (39) is preferably provided on the outer circumferential surface of the hollow cylinder, which connects the outer circumferential surface of the hollow cylinder to the inner circumferential surface, wherein the turbulence recess (39) is arranged in the axial direction in a section of the hollow cylinder which lies in a region of an opening of the main fluid flow connection (36) in the mixing space (M) and wherein the turbulence recess (39) is preferably designed as an elongated hole.

12. Method for conditioning an operating medium flowing in a test object circuit (PK) of a test object (P) mounted on a test bench to a predefined setpoint temperature (T_SOLL), characterized in that a mixing unit (3) is fluidically integrated into the test object circuit (PK) in order to form a part of the test object circuit (PK), wherein operating medium of the test object circuit (PK) to be conditioned is supplied to the mixing unit (3) via at least one test object circuit supply connection (26a) and operating medium conditioned to the predefined setpoint temperature (T_SOLL) is discharged from the mixing unit (3) via at least one test object circuit outlet connection (26b), wherein at least operating medium with a predefined conditioning temperature (T1, T2) and operating medium with a relatively higher or lower neutral temperature (T3) is supplied to the mixing unit (3) via at least one conditioning unit supply connection (27a), which operating medium is mixed in a mixing region (28) provided within the mixing unit (3) with the supplied operating medium of the test object circuit (PK) and is discharged from the mixing unit (3) via at least one conditioning unit return connection (27b), wherein a flow rate of the operating medium with the conditioning temperature (T1, T2) and a flow rate of the operating medium with the neutral temperature (T3) is adjusted as a function of the predefined setpoint temperature (T_SOLL).

13. Method according to claim 12, characterized in that at least one actual temperature (T_IST) of the operating medium is determined in the test object circuit (PK) or in the conditioning circuit (KK) and is supplied to a control unit (20, 21), wherein the control unit (20, 21) controls the flow rate of the operating medium with the conditioning temperature (T1, T2) and the flow rate of the operating medium at the neutral temperature (T3) as a function of the determined actual temperature (T_IST) and the predefined setpoint temperature (T_SOLL).

14. Method according to claim 13, characterized in that the actual temperature (T_IST) is calculated based on Richmann's law of mixtures, preferably according to T _ IST = mx * Tx + m 3 * T 3 mx + m 3 with a mass flow rate (mx) of the operating medium with the conditioning temperature (T1, T2) and a mass flow rate (m3) of the operating medium with the neutral temperature (T3).

15. Method according to claim 12 or 13, characterized in that the operating medium supplied to the mixing unit (3) via the at least one conditioning unit supply connection (27a) flows counter to a flow direction of the test object circuit (PK) to the at least one conditioning unit return connection (27b).

16. Method according to any of claims 12 to 15, characterized in that an actual pressure loss (Δp_IST) is measured in the testing object circuit (PK) in the mixing unit (3), and in that the flow rate of the operating medium with the conditioning temperature (T1, T2) and the flow rate of the operating medium with the neutral temperature (T3) are fixed in such a way and / or a flow cross section of a throttle point (29) provided in the mixing region (28) is fixed in such a way that the pressure loss (Δp) in the test object circuit (PK) of the mixing unit (3) is adjusted, preferably compensated, to a predefined setpoint pressure loss (Δp_SOLL).