A device and method for testing heat transfer and flow resistance coefficient of cooling medium

Abstract

The present invention relates to a device and method for testing the heat exchange and flow resistance coefficient of a cooling medium, wherein the method comprises: constructing a cooling medium testing device and determining a cooling medium to be tested for inputting into the cooling medium testing device; wherein the cooling medium testing device comprises: a connecting flange, a single-channel cooling flow channel, a temperature sensor and a pressure sensor; the temperature sensors are arranged at equal intervals on the single-channel cooling flow channel along the circumference of the connecting flange; the pressure sensors are arranged at equal intervals on the single-channel cooling flow channel along the circumference of the connecting flange; the connecting flange is connected to the outlet of an engine combustion chamber and the cooling medium to be tested is input into the single-channel cooling flow channel, so as to heat the connecting flange based on the high-temperature combustion gas outputted from the engine combustion chamber; the temperature and pressure of adjacent positions of the interval section on the single-channel cooling flow channel are respectively collected based on the temperature sensor and the pressure sensor, and the heat exchange coefficient and flow resistance coefficient of the cooling medium to be tested are obtained after calculation based on the temperature and pressure.

Description

Technical Field

[0001] The present invention relates to the field of aerospace, and in particular to a device and method for testing heat exchange and flow resistance coefficient of a cooling medium. Background Art

[0002] Due to their high-temperature operating environments, engines often utilize active cooling structures as a thermal protection design solution. Commonly used cooling media for engines include hydrocarbon fuels such as kerosene and methane. Their heat exchange and flow resistance characteristics are key to the design of active cooling channels. Insufficient heat exchange between the cooling medium and the cooling channels can lead to overheating and overheating of the cooling channels, which in turn affects the engine's service life and operational reliability. Excessive resistance to the flow of the cooling medium in the cooling channels can lead to pressure drop losses in the channels and excessive operating pressure in the cooling medium supply pump, resulting in excessive pump energy consumption.

[0003] The heat transfer and flow resistance characteristics of the coolant in the cooling channel are related to the coolant's form, physical properties, flow state, and the size and surface roughness of the cooling channel. During the temperature rise process, the coolant may be in liquid, gaseous, or a mixed gas-liquid state. Rapid changes in the coolant's physical properties, such as specific heat, density, and viscosity, at different temperatures and operating pressures will cause changes in the coolant's heat transfer and flow resistance characteristics. In addition, changes in the coolant flow rate, flow velocity, and cooling channel size will cause the coolant to exhibit laminar flow, turbulent flow, or a combination of the two in the cooling channel. Taking all of the above factors into account, the heat transfer and flow resistance characteristics of the coolant in the engine's active cooling channel are complex and variable.

[0004] Conventional testing methods for cooling medium heat transfer and flow resistance coefficients primarily rely on single-tube heating. However, due to its slow heating rate and relatively uniform heating of the cooling medium, this method cannot simulate the thermal environment within the engine cooling channel, and therefore cannot accurately capture the flow patterns of the cooling medium within the engine cooling channel. Furthermore, single-tube heating tests require a long heating time for the cooling medium to reach steady-state thermal equilibrium, resulting in lengthy testing cycles and significant labor and material resources. Summary of the Invention

[0005] The object of the present invention is to provide a device and method for testing the heat transfer and flow resistance coefficient of a cooling medium.

[0006] To achieve the above-mentioned object of the invention, the present invention provides a method for testing the heat transfer and flow resistance coefficient of a cooling medium, comprising the following steps:

[0007] S1. Construct a cooling medium test device and determine the cooling medium to be tested for input into the cooling medium test device; wherein the cooling medium test device includes: a connecting flange, a single cooling channel arranged on the outer side of the connecting flange, and a temperature sensor and a pressure sensor arranged on the single cooling channel;

[0008] Along the circumference of the connecting flange, the single cooling channel is regularly arranged on the outer side of the connecting flange in a circuitous manner;

[0009] The temperature sensors are arranged at equal intervals on the single cooling channel along the circumference of the connecting flange;

[0010] The pressure sensors are arranged at equal intervals on the single cooling channel along the circumference of the connecting flange;

[0011] S2. The connecting flange is connected to the outlet of the engine combustion chamber and the cooling medium to be tested is input into the single cooling channel to heat the connecting flange based on the high-temperature gas output from the engine combustion chamber;

[0012] S3. Based on the temperature sensor and the pressure sensor, the temperature and pressure of adjacent positions of equally spaced sections on the single cooling channel are respectively collected, and the heat transfer coefficient and flow resistance coefficient of the cooling medium to be measured are obtained through calculation based on the temperature and the pressure.

[0013] According to one aspect of the present invention, the input port and the output port of the single-channel cooling channel are arranged adjacent to each other;

[0014] The rib width of the single-channel cooling channel is consistent along the entire length, the channel width is consistent along the entire length, and the channel height is consistent along the entire length.

[0015] According to one aspect of the present invention, the temperature sensors and the pressure sensors adjacent to each other at equal intervals on the single cooling channel are installed in a staggered arrangement.

[0016] According to one aspect of the present invention, the input port of the single-channel cooling channel is provided with a flow control device;

[0017] The flow control device is a flow pump, or the flow control device is connected to a venturi tube of a boosting pipe, so as to control the cavitation flow at a preset pressure.

[0018] According to one aspect of the present invention, the output port of the single-channel cooling channel is provided with an orifice throttling member for controlling the outlet pressure of the output port.

[0019] According to one aspect of the present invention, in step S3, the temperature and pressure of adjacent positions of equally spaced segments on the single-channel cooling channel are respectively collected based on the temperature sensor and the pressure sensor, and the heat transfer coefficient and flow resistance coefficient of the cooling medium to be measured are obtained based on the temperature and the pressure. The heat transfer coefficient is the heat transfer coefficient at the average temperature and average pressure of the adjacent interval segments, and the flow resistance coefficient is the flow resistance coefficient at the average temperature of the adjacent interval segments.

[0020] According to one aspect of the present invention, the heat transfer coefficient is obtained based on the following steps, which include:

[0021] S3a1. Obtain the inlet mass flow rate of the cooling medium to be measured at the input port , and obtain the inlet temperature of the cooling medium to be measured at adjacent positions of the equally spaced segments and outlet temperature , to obtain the heat absorption power of the high temperature gas on the cooling medium to be tested during the equal interval period , and is expressed as:

[0022]

[0023] in, H i 、 H i+1 The cooling medium to be tested is at the temperature and temperature Enthalpy value at ;

[0024] S3a2. Obtain the average heat flux density of the high-temperature gas heating the connecting flange when the cooling medium to be tested flows through the equally spaced segments. q i , and is expressed as:

[0025]

[0026] in, T r The recovery temperature of the high-temperature fuel gas output from the engine combustion chamber. h 0 is the heat transfer coefficient between high temperature gas and the connecting flange wall, is the heat transfer coefficient between the cooling medium to be measured and the connecting flange wall, η p is the rib effect coefficient, t is the side wall thickness of the connecting flange, λ is the thermal conductivity of the connecting flange;

[0027] S3a3. Obtaining the heating power of the cooling medium to be tested when it flows through the equally spaced segments , and is expressed as:

[0028]

[0029] in, A i The contact area between the high-temperature gas and the wall surface of the connecting flange when the cooling medium to be tested flows through the equally spaced sections;

[0030] S3a4. Based on the law of conservation of energy, establish the heat absorption power of the high-temperature gas in the same equal interval to the cooling medium to be tested The heating power when the cooling medium to be tested flows through the equally spaced segments The heat transfer coefficient is obtained by the equation:

[0031]

[0032] in, Represents the heat transfer coefficient.

[0033] According to one aspect of the present invention, the flow resistance coefficient is obtained based on the following steps, which include:

[0034] S3b1. Obtain the pressure loss of the cooling medium to be tested in the single cooling channel, and express it as:

[0035]

[0036] in, λ is the flow resistance coefficient, l is the flow channel length, d is the hydraulic diameter of the cooling channel, ρ is the cooling medium density, , b The height and width of a single cooling channel;

[0037] S3b2. Obtain the inlet temperature of the cooling medium to be measured flowing through adjacent positions of the equally spaced segments T i , outlet temperature T i+1 and inlet pressure P i , outlet pressure P i+1 , and obtain the flow resistance at the average temperature of the equally spaced segments, which is expressed as:

[0038]

[0039] in, ρ i Indicates the average temperature of the cooling medium to be tested ( T i + T i+1) / 2;

[0040] S3b3. Based on the average temperature of the cooling medium flowing through the equally spaced segments ( T i + T i+1 ) / 2 to obtain its flow resistance coefficient, which can be expressed as:

[0041]

[0042]

[0043] in, λ i represents the flow resistance coefficient, λ oi It represents the flow resistance coefficient of the cooling medium to be tested flowing through the equally spaced sections at room temperature. ρ 0 is the density of the cooling medium to be tested at room temperature, P 0i 、 P 0i+1 Indicates mass flow rate at room temperature The inlet pressure and outlet pressure of the cooling medium to be measured at adjacent positions of the equally spaced segments, Δ p 0i It represents the flow resistance of the cooling medium to be tested flowing through equally spaced segments at room temperature.

[0044] To achieve the above-mentioned object, the present invention provides a testing device for the aforementioned heat transfer and flow resistance coefficient testing method, comprising: a connecting flange, a single-channel cooling channel arranged on the outer side of the connecting flange, and a temperature sensor and a pressure sensor arranged on the single-channel cooling channel;

[0045] Along the circumference of the connecting flange, the single cooling channel is regularly arranged on the outer side of the connecting flange in a circuitous manner;

[0046] The temperature sensors are arranged at equal intervals on the single cooling channel along the circumference of the connecting flange;

[0047] The pressure sensors are arranged at equal intervals on the single-path cooling channel along the circumference of the connecting flange.

[0048] According to one aspect of the present invention, the input port and the output port of the single-channel cooling channel are arranged adjacent to each other;

[0049] The rib width of the single-channel cooling channel is consistent along the entire length, the channel width is consistent along the entire length, and the channel height is consistent along the entire length.

[0050] The temperature sensors and pressure sensors adjacent to each other at equal intervals on the single cooling channel are installed in a staggered arrangement;

[0051] The input port of the single-channel cooling channel is provided with a flow control device;

[0052] The output port of the single-channel cooling channel is provided with an orifice throttling member for controlling the outlet pressure of the output port;

[0053] The flow control device is a flow pump, or the flow control device is connected to a venturi tube of a boosting pipe, so as to control the cavitation flow at a preset pressure.

[0054] According to one solution of the present invention, the present invention can quickly test the temperature and pressure parameter changes of the cooling medium to be tested in the cooling channel under different mass flow rates. Compared with the traditional single-tube heating test method, the present invention has the characteristics of low test cost and short cycle.

[0055] According to one embodiment of the present invention, the high-temperature combustion gas at the engine combustion chamber outlet heats the test device's cooling medium with excellent circumferential uniformity and high heater efficiency. Furthermore, by ensuring consistent operating conditions in the engine combustion chamber, the thermal environment for heating the cooling medium remains consistent under each test condition.

[0056] According to one solution of the present invention, the present invention can test the temperature and pressure parameter changes of the cooling medium in the cooling channel along the cooling channel under the rated flow and back pressure of the cooling medium through a single test, and the validity and consistency of the test data are good.

[0057] According to one solution of the present invention, the present invention can fully obtain the heat transfer and flow resistance coefficients of the cooling medium to be tested at different operating temperatures and pressures, thereby improving the accuracy of the heat transfer and pressure drop engineering design of the engine active cooling channel. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] Figure 1 is a block diagram schematically showing the steps of a method for testing heat transfer and flow resistance coefficient according to one embodiment of the present invention;

[0059] Figure 2 is a structural diagram schematically showing a testing device according to an embodiment of the present invention;

[0060] Figure 3 It is a schematic representation Figure 2 A magnified view of a local location;

[0061] Figure 4 FIG. 1 is a diagram schematically showing the distribution of temperature sensors and pressure sensors in a testing device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0062] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be derived from these drawings without inventive effort.

[0063] When describing the embodiments of the present invention, the orientation or positional relationship expressed by the terms "longitudinal", "transverse", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" are based on the orientation or positional relationship shown in the relevant drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation. Therefore, the above terms should not be understood as limiting the present invention.

[0064] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. The embodiments cannot be described one by one here, but the embodiments of the present invention are not limited to the following embodiments.

[0065] Combine Figure 1 、 Figure 2 、 Figure 3 and Figure 4 As shown, according to one embodiment of the present invention, a method for testing heat transfer and flow resistance coefficient of a cooling medium of the present invention includes the following steps:

[0066] S1. Construct a cooling medium test device and determine a cooling medium to be tested for input into the cooling medium test device; the cooling medium test device comprises: a connecting flange 11, a single cooling channel 12 arranged on an outer side of the connecting flange 11, and a temperature sensor 13 and a pressure sensor 14 arranged on the single cooling channel 12; the single cooling channel 12 is arranged regularly on the outer side of the connecting flange 11 in a circuitous manner along the circumference of the connecting flange 11; the temperature sensors 13 are arranged at equal intervals on the single cooling channel 12 along the circumference of the connecting flange 11; and the pressure sensors 14 are arranged at equal intervals on the single cooling channel 12 along the circumference of the connecting flange 11;

[0067] S2. The connecting flange 11 is connected to the outlet of the engine combustion chamber and the cooling medium to be tested is input to the single cooling channel 12, based on the high-temperature gas output of the engine combustion chamber to heat the connecting flange 11;

[0068] S3. The temperature and pressure of adjacent positions of the interval section on the single cooling channel 12 are respectively collected using the temperature sensor 13 and the pressure sensor 14, and the heat transfer coefficient and flow resistance coefficient of the cooling medium to be measured are obtained through calculation based on the temperature and pressure.

[0069] Combine Figure 1 、 Figure 2 、 Figure 3 and Figure 4 As shown, according to one embodiment of the present invention, the connecting flange 11 comprises a mounting body and a connecting ring disposed at one end of the mounting body. The connecting ring has multiple through-holes spaced evenly apart to facilitate the installation and fixation of the connecting flange 11 using connectors. In this embodiment, the mounting body is entirely cylindrical, and a single cooling channel 12 can be disposed on its outer surface. The single cooling channel 12 is fixedly connected to the mounting body, contacting and enabling heat exchange with the mounting body.

[0070] In this embodiment, the single-channel cooling channel 12 includes an axial channel portion and a radial connecting portion. The axial connecting portion is a straight tube, and multiple axial connecting portions are arranged in parallel at equal intervals on the connecting flange 11. The radial connecting portions are respectively connected to adjacent axial channel portions, thereby achieving a tortuous structure in which multiple axial channel portions are sequentially connected end to end. Of course, in this embodiment, to ensure unidirectional flow of the cooling medium to be measured, two of the axial channel portions are selected as the head and tail portions of the entire single-channel cooling channel 12, and by providing an input port 121 and an output port 122 at each end, unidirectional flow of the cooling medium to be measured from input to output is achieved.

[0071] In this embodiment, the input port 121 and the output port 122 of the single cooling channel 12 are arranged adjacent to each other, that is, in the axial direction of the connecting flange 11, the input port 121 and the output port 122 are respectively arranged at the same side ends of two adjacent axial channel parts, so as to achieve the unification of the input and output positions of the cooling medium to be measured, and facilitate the installation of the corresponding structure to simplify the overall structure.

[0072] In this embodiment, the rib width, channel width, and channel height of the single cooling channel 12 are consistent along the entire channel; wherein the single cooling channel 12 adopts a rectangular channel with a rectangular cross-section.

[0073] In this embodiment, the connecting flange 11 can be divided into a plurality of equally spaced segments along the circumference of the connecting flange 11, and the temperature sensor 13 and the pressure sensor 14 can be arranged at equal intervals based on the positions of the equally spaced segments, wherein the positions of the temperature sensor 13 and the pressure sensor 14 are spaced apart along the axial direction of the connecting flange 11.

[0074] Combine Figure 1 、 Figure 2 、 Figure 3 and Figure 4 As shown, according to one embodiment of the present invention, adjacent temperature sensors 13 and pressure sensors 14 at equal intervals along a single cooling channel 12 are installed in a staggered arrangement. Specifically, in the axial direction of the connecting flange 11, the temperature sensors 13 and pressure sensors 14 are arranged to form two circles of measurement positions. Within each circle of measurement positions, the temperature sensors 13 and pressure sensors 14 are arranged in an alternating manner. Furthermore, in the axial direction of the connecting flange 11, the temperature sensors 13 and pressure sensors 14 are spaced apart in the same axial flow channel portion, thereby achieving a staggered arrangement.

[0075] Combine Figure 1 、 Figure 2 、 Figure 3 and Figure 4 As shown, according to one embodiment of the present invention, the inlet 121 of the single-channel cooling channel 12 is provided with a flow control device; the flow control device is a flow pump, which realizes real-time flow control by using the flow pump. Alternatively, the flow control device is connected to a venturi tube of the boosting pipe to control the cavitation flow at a preset pressure. In this case, based on the boosting of the boosting tank, the flow control is achieved by the cavitation flow of the venturi tube at a certain rated pressure.

[0076] Combine Figure 1 、 Figure 2 、 Figure 3 and Figure 4 As shown, according to one embodiment of the present invention, the output port 122 of the single-channel cooling channel 12 is provided with an orifice throttling element for controlling the outlet pressure of the output port 122. In this embodiment, the orifice throttling element has a variety of specifications. Thus, the outlet pressure can be adjusted by using orifice throttling elements of different specifications to meet measurement requirements under different pressure parameters and temperatures of the cooling medium to be measured.

[0077] Combine Figure 1 、 Figure 2 、 Figure 3 and Figure 4 As shown, according to one embodiment of the present invention, in step S3, the temperature and pressure of the adjacent positions of the interval segments on the single-channel cooling channel 12 are respectively collected based on the temperature sensor 13 and the pressure sensor 14, and the heat transfer coefficient and flow resistance coefficient of the cooling medium to be measured are obtained based on the temperature and pressure. The heat transfer coefficient is the heat transfer coefficient at the average temperature and average pressure of the adjacent interval segments, and the flow resistance coefficient is the flow resistance coefficient at the average temperature of the adjacent interval segments.

[0078] Combine Figure 1 、 Figure 2 、 Figure 3 and Figure 4 As shown, according to one embodiment of the present invention, the convection heat transfer coefficient between the cooling medium and the solid wall represents the heat transfer capacity between the cooling medium and the solid surface, that is, the heat exchange amount between the cooling medium and the solid wall by convection per unit time and per unit area, and the unit is W / (m 2 K), thus, the size of the heat transfer coefficient reflects the strength of convective heat transfer. In this embodiment, the heat transfer coefficient is obtained based on the following steps, which include:

[0079] S3a1. Obtain the inlet mass flow rate of the cooling medium to be measured at the input port 121 , and obtain the temperature of adjacent positions of the equally spaced segments through which the cooling medium to be measured flows T i and temperature T i+1 , and then the heat absorption power of the high temperature gas on the cooling medium to be tested in the equal interval section can be calculated under steady state , and is expressed as:

[0080]

[0081] in, H i 、 H i+1 The cooling medium to be tested is at the temperature and temperature Enthalpy value at ;

[0082] S3a2. Obtain the average heat flux density of the high-temperature gas heating the connecting flange 11 when the cooling medium to be tested flows through the equally spaced segments. q i , and is expressed as:

[0083]

[0084] in, T r The recovery temperature of the high-temperature fuel gas output from the engine combustion chamber. h 0 is the heat transfer coefficient between high temperature gas and the wall of connecting flange 11, is the heat transfer coefficient between the cooling medium to be measured and the wall of the connecting flange 11, η p is the rib effect coefficient, t is the side wall thickness of the connecting flange 11, λ is the thermal conductivity of the connecting flange 11;

[0085] S3a3. Obtain the heating power when the cooling medium to be tested flows through the equally spaced segments , and is expressed as:

[0086]

[0087] in, A i is the contact area between the high-temperature gas and the wall surface of the connecting flange 11 when the cooling medium to be measured flows through the equally spaced sections;

[0088] S3a4. Based on the law of conservation of energy, establish the heat absorption power of the high-temperature gas in the same equal interval to the cooling medium to be tested The heating power when the cooling medium to be measured flows through the equal interval section Equal relationship, in order to obtain the average temperature ( T i + T i+1 ) / 2 and the average pressure ( P i + P i+1 ) / 2, and is expressed as:

[0089]

[0090] in, Represents the heat transfer coefficient.

[0091] In this embodiment, the heat transfer coefficient between the cooling medium to be tested and the wall surface of the connecting flange 11 at a certain rated flow rate, working back pressure and corresponding working temperature can be obtained by repeating the test multiple times.

[0092] Combine Figure 1 、 Figure 2 、 Figure 3 and Figure 4 As shown, according to one embodiment of the present invention, the flow resistance coefficient is obtained based on the following steps, which include:

[0093] S3b1. Obtain the pressure loss of the cooling medium to be tested in the single cooling channel 12, wherein the pressure loss in the single cooling channel 12 includes two types of along-line pressure loss and local pressure loss, which are expressed as:

[0094]

[0095] in, λ is the flow resistance coefficient, l is the flow channel length, d is the hydraulic diameter of the cooling channel, ρ is the density of the cooling medium, u is the flow rate.

[0096] The flow resistance coefficient is mainly related to the flow state of the cooling medium to be measured, the surface roughness of the channel, the geometric shape, etc. In engineering applications, it is often fitted by the Reynolds number Re.

[0097] The flow state of the cooling medium to be tested in the single-channel cooling channel 12 is mainly divided into two types: laminar flow and turbulent flow, which is mainly related to the Reynolds number Re and is expressed as:

[0098]

[0099] in, v is the kinematic viscosity of the cooling medium to be tested.

[0100] For a rectangular channel, the hydraulic diameter d Expressed as:

[0101]

[0102] in, , b It is the height and width of the single cooling channel 12.

[0103] The cooling medium to be measured is at mass flow rate The flow velocity of a channel section is u Expressed as:

[0104]

[0105] in, ρ Indicates the density of the cooling medium.

[0106] Furthermore, due to the density of the cooling medium to be tested ρ , kinematic viscosity v It changes with the change of temperature and pressure, which causes the flow resistance coefficient to change with the change of the temperature and pressure of the cooling medium to be measured; thus, the pressure loss in the single cooling channel 12 can be transformed into:

[0107] .

[0108] S3b2. Obtain the temperature of adjacent positions of the cooling medium flowing through the equally spaced segments T i ,temperature T i+1 and pressure P i ,pressure P i+1 , and obtain the flow resistance at the average temperature of the equal interval segment; in this embodiment, at room temperature, the mass flow rate is used The pressures of the cooling medium to be tested at adjacent positions in a certain equally spaced segment are P0i 、 P 0i +1, then the flow resistance of the cooling medium to be measured at a certain equal interval at room temperature is Δ p 0i for:

[0109]

[0110] in, ρ 0 is the density of the cooling medium to be tested at room temperature, λ 0i It is the flow resistance coefficient of the cooling medium to be tested in the equally spaced sections at room temperature.

[0111] Furthermore, based on the flow resistance coefficient of each equally spaced segment at room temperature, the average flow resistance coefficient at room temperature is obtained. λ 0, and is represented by:

[0112]

[0113] in, n Indicates the number of equally spaced segments.

[0114] By heating the test device, the inlet temperature of adjacent positions at equal intervals is measured T i , outlet temperature T i+1 , inlet pressure of cooling medium P i , outlet pressure P i+1 , then a certain equal interval segment has an average temperature ( T i + T i+1 ) / 2 flow resistance is

[0115]

[0116] in, ρ i Indicates the average temperature of the cooling medium to be tested ( T i + T i+1 ) / 2;

[0117] S3b3. Obtain the flow resistance coefficient of the cooling medium to be measured based on the flow resistance of the cooling medium flowing through the equally spaced segments at the average temperature, and express it as:

[0118]

[0119]

[0120] in, λ i represents the flow resistance coefficient, λ oi It indicates the flow resistance coefficient of the cooling medium to be tested flowing through the equally spaced sections at room temperature. ρ 0 is the density of the cooling medium to be tested at room temperature, P 0i 、 P 0i+1 Indicates mass flow rate at room temperature The pressure of the cooling medium to be measured flowing through adjacent positions of the equally spaced segments, Δ p 0i It indicates the flow resistance of the cooling medium to be tested flowing through equally spaced sections at room temperature.

[0121] In this embodiment, the flow resistance coefficient of the cooling medium to be tested flowing through the single cooling channel 12 at a certain rated flow rate, working back pressure and corresponding working temperature can be obtained by repeating the test multiple times.

[0122] Combine Figure 2 、 Figure 3 and Figure 4 As shown, the present invention provides a test device for the aforementioned heat exchange and flow resistance coefficient test method, comprising: a connecting flange 11, a single-channel cooling channel 12 arranged on the outer side of the connecting flange 11, and a temperature sensor 13 and a pressure sensor 14 arranged on the single-channel cooling channel 12; in this embodiment, along the circumference of the connecting flange 11, the single-channel cooling channel 12 is regularly arranged on the outer side of the connecting flange 11 in a circuitous manner; further, along the circumference of the connecting flange 11, the temperature sensors 13 are arranged at equal intervals on the single-channel cooling channel 12; along the circumference of the connecting flange 11, the pressure sensors 14 are arranged at equal intervals on the single-channel cooling channel 12.

[0123] Combine Figure 2 、 Figure 3 and Figure 4 As shown, according to one embodiment of the present invention, the input port 121 and the output port 122 of the single-channel cooling channel 12 are arranged adjacent to each other; wherein, the rib width along the single-channel cooling channel 12 is consistent, the channel width along the channel is consistent, and the channel height along the channel is consistent. In this embodiment, the temperature sensors 13 and pressure sensors 14 adjacent to each other at equal intervals on the single-channel cooling channel 12 are installed in a staggered arrangement; further, the input port 121 of the single-channel cooling channel 12 is provided with a flow control device; the output port 122 of the single-channel cooling channel 12 is provided with an orifice throttling member for controlling the outlet pressure of the output port 122. In this embodiment, the flow control device is a flow pump, or the flow control device is connected to a venturi tube of a boost pipe for controlling the cavitation flow at a preset pressure.

[0124] The above contents are merely examples of specific solutions of the present invention. For devices and structures not described in detail, it should be understood that they can be implemented by adopting general devices and methods available in the art.

[0125] The above description is merely one embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that the present invention is susceptible to various modifications and variations. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A method for testing heat transfer and flow resistance coefficient of a cooling medium, characterized in that: The following steps are involved: S1. Construct a cooling medium test device and determine a cooling medium to be tested for input into the cooling medium test device; wherein the cooling medium test device comprises: a connecting flange (11), a single-channel cooling channel (12) arranged on the outer side of the connecting flange (11), a temperature sensor (13) and a pressure sensor (14) arranged on the single-channel cooling channel (12); an input port (121) and an output port (122) of the single-channel cooling channel (12) are arranged adjacent to each other; Along the circumference of the connecting flange (11), the single-path cooling channel (12) is regularly arranged on the outer side of the connecting flange (11) in a circuitous manner; The temperature sensors (13) are arranged at equal intervals on the single-path cooling channel (12) along the circumference of the connecting flange (11); The pressure sensors (14) are arranged at equal intervals on the single-path cooling channel (12) along the circumference of the connecting flange (11); S2. Connecting the connecting flange (11) to the outlet of the engine combustion chamber and inputting the cooling medium to be tested into the single-channel cooling channel (12) to heat the connecting flange (11) based on the high-temperature gas output from the engine combustion chamber; S3. Based on the temperature sensor (13) and the pressure sensor (14), the temperature and pressure of adjacent positions of the evenly spaced segments on the single cooling channel (12) are respectively collected, and the heat transfer coefficient and flow resistance coefficient of the cooling medium to be measured are obtained after calculation based on the temperature and the pressure; wherein the heat transfer coefficient is obtained based on the following steps, which include: S3a1. Obtaining the inlet mass flow rate of the cooling medium to be measured at the input port (121) , and obtain the inlet temperature of the cooling medium to be measured at adjacent positions of the equally spaced segments and outlet temperature , to obtain the heat absorption power of the cooling medium to be tested on the high temperature gas when the cooling medium to be tested is in the equal interval segment , and is expressed as: in, H i 、 H i+1 The cooling medium to be tested is at the temperature and temperature Enthalpy value at ; S3a2. Obtain the average heat flux density of the high-temperature gas heating the connecting flange (11) when the cooling medium to be tested flows through the equally spaced sections. q i , and is expressed as: in, T r The recovery temperature of the high-temperature fuel gas output from the engine combustion chamber. h 0 is the heat transfer coefficient between the high temperature gas and the wall of the connecting flange (11), is the heat transfer coefficient between the cooling medium to be measured and the wall of the connecting flange (11), η p is the rib effect coefficient, t is the side wall thickness of the connecting flange (11), λ is the thermal conductivity of the connecting flange (11); S3a3. Obtaining the heating power of the cooling medium to be tested when it flows through the equally spaced segments , and is expressed as: in, A i is the contact area between the high-temperature gas and the wall surface of the connecting flange (11) when the cooling medium to be measured flows through the equally spaced sections; S3a4. Based on the law of conservation of energy, establish the heat absorption power of the cooling medium to be tested on the high-temperature gas in the same equal interval The heating power when the cooling medium to be tested flows through the equally spaced segments The heat transfer coefficient is obtained by the equation: in, represents the heat transfer coefficient; The flow resistance coefficient is obtained based on the following steps, which include: S3b1. Obtain the pressure loss of the cooling medium to be tested in the single-pass cooling channel (12), and express it as: in, λ is the flow resistance coefficient, l is the flow channel length, d is the hydraulic diameter of the cooling channel, ρ is the density of the cooling medium, , b is the height and width of the single cooling channel (12); S3b2. Obtain the inlet temperature of the cooling medium to be measured flowing through adjacent positions of the equally spaced segments T i , outlet temperature T i+1 and inlet pressure P i , outlet pressure P i+1 , and obtain the average temperature of the equally spaced segments ( T i + T i+1 ) / 2, which is expressed as: in, ρ i Indicates the average temperature of the cooling medium to be tested ( T i + T i+1 ) / 2; S3b3. Based on the average temperature of the cooling medium flowing through the equally spaced segments ( T i + T i+1 ) / 2 to obtain its flow resistance coefficient, which can be expressed as: in, λ i represents the flow resistance coefficient, λ oi It represents the flow resistance coefficient of the cooling medium to be tested flowing through the equally spaced sections at room temperature. ρ 0 is the density of the cooling medium to be tested at room temperature, P 0i 、 P 0i+1 Indicates mass flow rate at room temperature The inlet pressure and outlet pressure of the cooling medium to be measured at adjacent positions of the equally spaced segments, Δ p 0i It represents the flow resistance of the cooling medium to be tested flowing through equally spaced segments at room temperature.

2. The heat transfer and flow resistance coefficient testing method according to claim 1, characterized in that: The rib width of the single-channel cooling channel (12) is consistent along the entire length, the channel width is consistent along the entire length, and the channel height is consistent along the entire length.

3. The method for testing heat transfer and flow resistance coefficient according to claim 2, characterized in that: The temperature sensors (13) and the pressure sensors (14) adjacent to each other at equal intervals on the single-channel cooling channel (12) are installed in a staggered arrangement.

4. The method for testing heat transfer and flow resistance coefficient according to claim 2, characterized in that: The input port (121) of the single-channel cooling channel (12) is provided with a flow control device; The flow control device is a flow pump, or the flow control device is a venturi tube connected to a boost tank, so as to achieve flow control through cavitation flow at a preset pressure.

5. The method for testing heat transfer and flow resistance coefficient according to claim 4, characterized in that: The output port (122) of the single-channel cooling channel (12) is provided with an orifice throttling element for controlling the outlet pressure of the output port (122).

6. The method for testing heat transfer and flow resistance coefficient according to claim 5, characterized in that: In step S3, the temperature and pressure of adjacent positions of the equally spaced segments on the single-channel cooling channel (12) are respectively collected based on the temperature sensor (13) and the pressure sensor (14), and the heat transfer coefficient and flow resistance coefficient of the cooling medium to be measured are obtained based on the temperature and the pressure, wherein the heat transfer coefficient is the heat transfer coefficient at the average temperature and average pressure of the adjacent interval segments, and the flow resistance coefficient is the flow resistance coefficient at the average temperature of the adjacent interval segments.

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