An air intake system for an engine test bench

Abstract

An engine test bench air intake system comprises a supply source, a temperature simulation unit and a simulation cabin; the supply source comprises a fuel supply source, an oxygen supply source, an engine intake supply source and an alcohol supply source; the temperature simulation unit comprises a tube body and a shell, the tube body is located inside the shell, the tube body is a first medium channel, and the space between the outer wall of the tube body and the inner wall of the shell forms a second medium channel; the test engine is located in the simulation cabin; the fuel supply source is connected to the test engine through a pipeline, the oxygen supply source and the engine intake supply source are connected to the inlet of the second medium channel through pipelines respectively, the outlet of the second medium channel is connected to the air intake of the test engine through a pipeline, and the alcohol supply source is connected to the inlet of the first medium channel through a pipeline after passing through an igniter.

Description

Technical Field

[0001] The invention relates to the technical field of test measurement, in particular to an air intake system of an engine test bench. Background Art

[0002] Before an aircraft engine is tested for flight, it is necessary to conduct high-altitude simulation tests on the ground. During the engine test, a set of intake parameters is required, including total intake pressure, intake air flow, intake oxygen content, total intake temperature, and engine fuel supply, which are called intake state points. After reaching the set value and stabilizing, its performance and parameters are recorded or its performance is evaluated. The existing engine test bench technology has no mature technology for engine intake simulation, and there is no accurate theoretical judgment method for when the simulation state reaches a stable state, resulting in poor test simulation effects, long test cycles, high costs, and serious waste of resources. Summary of the invention

[0003] The technical problem solved by the present invention is to overcome the deficiencies of the prior art and provide an engine test bench air intake system.

[0004] The technical solution of the present invention is: an engine test bench air intake system, including a supply source, a temperature simulation unit and a simulation cabin; the supply source includes a fuel supply source, an oxygen supply source, an engine intake supply source and an alcohol supply source; the temperature simulation unit includes a tube body and a shell, the tube body is located inside the shell, the tube body is a first medium channel, and the space between the outer wall of the tube body and the inner wall of the shell forms a second medium channel; the test engine is located in the simulation cabin; the fuel supply source is connected to the test engine through a pipeline, the oxygen supply source and the engine intake supply source are connected to the inlet of the second medium channel through pipelines respectively, the outlet of the second medium channel is connected to the air intake of the test engine through a pipeline, and the alcohol supply source is connected to the inlet of the first medium channel through a pipeline after passing through an igniter.

[0005] Furthermore, an engine fuel supply flow regulating valve and an engine fuel supply shut-off valve are provided on a pipeline connecting the fuel supply source and the tested engine.

[0006] Furthermore, an oxygen supply flow regulating valve and an oxygen supply stop valve are provided on the pipeline connecting the oxygen supply source and the inlet of the second medium channel.

[0007] Furthermore, an engine intake air supply pressure regulating valve is provided on the pipeline connecting the engine intake air supply source and the inlet of the second medium channel.

[0008] Furthermore, an alcohol supply flow regulating valve and an alcohol supply stop valve are provided on the pipeline connecting the alcohol supply source and the inlet of the first medium channel, and the outlet of the first medium channel is connected to the outside.

[0009] The advantages of the present invention compared with the prior art are:

[0010] 1. The engine test bench air intake system of the present invention simulates the engine intake flow rate and the total intake pressure through the engine intake supply source. At the same time, oxygen is supplemented for the engine intake through the oxygen supply source and the engine intake temperature is simulated through the temperature simulation unit, thereby realizing a true simulation of the engine intake, having a simple structure and high simulation accuracy.

[0011] 2. The engine test bench air intake system of the present invention is provided with an alcohol supply source, and the alcohol is ignited by an igniter to generate heat which is exchanged with the engine air intake in the temperature simulation unit to achieve the regulation of the engine air intake temperature.

[0012] 3. The engine test bench air intake system of the present invention realizes adjustable flow and pressure of relevant supply sources by setting various valves, thereby realizing simulation of multiple state points. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 The figure is a schematic diagram of the structure of the air intake system of the engine test bench of the present invention.

[0014] Figure 2 It is a partial structural schematic diagram of the temperature simulation unit of the intake system of the engine test bench of the present invention.

[0015] Figure 3 The present invention is a flow chart of the method for using the engine test bench air intake system. DETAILED DESCRIPTION

[0016] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0017] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection", "connection", and "abutment" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0018] An engine test bench intake system is used for an engine high-altitude multi-state point intake simulation test, wherein the intake parameters of the state points include engine intake total pressure, intake air flow, intake oxygen composition, intake total temperature, and engine fuel supply.

[0019] The engine test bench air intake system includes a supply source, a temperature simulation unit 200 and a simulation cabin 300 .

[0020] The supply sources include a fuel supply source 110, an oxygen supply source 120, an engine intake supply source 130 and an alcohol supply source 140; the temperature simulation unit includes a tube body 210 and a shell 220, the tube body 210 is located inside the shell 220, the tube body 210 is a first medium channel, and the space between the outer wall of the tube body 210 and the inner wall of the shell 220 forms a second medium channel; when the temperature simulation unit 200 is working, the first medium flows in the first medium channel, and the second medium flows in the second medium channel, the temperature of the first medium is higher than that of the second medium, and the first medium and the second medium realize heat exchange through the tube wall of the tube body 210.

[0021] The test engine 400 is located in the simulation cabin 300 .

[0022] The fuel supply source 110 is connected to the test engine 400 through a pipeline, the oxygen supply source 120 and the engine intake supply source 130 are respectively connected to the inlet of the second medium channel through pipelines, and the outlet of the second medium channel is connected to the intake port of the test engine 400 through a pipeline, providing the test engine 400 with simulated engine intake flow, total intake pressure and oxygen content; the alcohol supply source 140 is connected to the inlet of the first medium channel through a pipeline after passing through an igniter, and the outlet of the first medium channel is connected to the outside world. The igniter ignites and burns the alcohol to generate heat, which is exchanged with the second medium in the second medium channel in the temperature simulation unit 200 to adjust the temperature of the second medium in the second medium channel, thereby realizing engine intake temperature simulation. The engine intake simulation of the present invention is realistic, high in precision, and simple in structure.

[0023] An engine fuel supply flow regulating valve 510 is provided on the pipeline connecting the fuel supply source 110 and the test engine 400, an oxygen supply flow regulating valve 530 is provided on the pipeline connecting the oxygen supply source 120 and the inlet of the second medium channel, an engine intake supply pressure regulating valve 550 is provided on the pipeline connecting the engine intake supply source 130 and the inlet of the second medium channel, and an alcohol supply flow regulating valve 560 is provided on the pipeline connecting the alcohol supply source 140 and the inlet of the first medium channel, so as to realize parameter adjustment of each supply source and meet the simulation of multiple state points.

[0024] Preferably, the engine test bench includes an engine fuel supply shut-off valve 520, an oxygen supply shut-off valve 540 and an alcohol supply shut-off valve 570, the engine fuel supply shut-off valve 520 is arranged on a pipeline connecting the fuel supply source 110 and the test engine 400; the oxygen supply shut-off valve 540 is arranged on a pipeline connecting the oxygen supply source 120 and the entrance of the second medium channel; the alcohol supply shut-off valve 570 is arranged on a pipeline connecting the alcohol supply source 140 and the entrance of the first medium channel. During the use of the engine test bench, the engine fuel supply shut-off valve 520 is opened before opening the engine fuel supply flow regulating valve 510, the oxygen supply shut-off valve 540 is opened before opening the oxygen supply flow regulating valve 530, and the alcohol supply shut-off valve 570 is opened before opening the alcohol supply flow regulating valve 560; the engine fuel supply shut-off valve 520 is closed after closing the engine fuel supply flow regulating valve 510, the oxygen supply shut-off valve 540 is closed after closing the oxygen supply flow regulating valve 530, and the alcohol supply shut-off valve 570 is closed after closing the alcohol supply flow regulating valve 560, so as to ensure the safety of the test bench in a non-experimental state.

[0025] The method for using the engine test bench air intake system comprises the following steps:

[0026] S100), engine intake total pressure and oxygen content regulation

[0027] The engine intake supply pressure regulating valve and the oxygen supply flow regulating valve are adjusted according to the total intake pressure and oxygen content at the first simulated state point, so that the total pressure and oxygen content of the second medium passing through the outlet of the second medium channel are the same as the total intake pressure and oxygen content of the engine at the first simulated state point.

[0028] S200), engine intake total temperature regulation

[0029] According to the total intake air temperature at the first simulation state point, the alcohol supply flow regulating valve is adjusted and the igniter is started to ignite the alcohol to burn the alcohol. The burning alcohol exchanges heat with the second medium in the second medium channel in the first medium channel, so that the total temperature of the second medium passing through the outlet of the second medium channel is the same as the total intake air temperature of the engine at the first simulation state point;

[0030] S210), adjusting the alcohol supply flow regulating valve according to the highest operating value that the temperature simulation unit can withstand, starting the igniter, igniting the alcohol to make it burn, and the burning alcohol exchanges heat with the second medium in the first medium channel and the second medium channel;

[0031] S220), maintaining the state of step S310 until the temperature simulation unit enters a stable working state;

[0032] S230), according to the total temperature of the second medium at the outlet of the second medium channel, the mass of the second medium in the second medium channel, the constant pressure specific heat of the second medium, the convection heat transfer coefficient of the outer wall of the tube body, the inner wall area of ​​the entire tube body, the mass of the first medium in the first medium channel, the constant pressure specific heat of the first medium, the convection heat transfer coefficient of the outer wall of the tube body, the outer wall area of ​​the entire tube body, and the total temperature of the second medium at the inlet of the second medium channel at the first simulation state point;

[0033] S240), adjusting the alcohol supply flow regulating valve to adjust the state of the first medium in the first medium channel from the highest operating value that the temperature simulation unit can withstand to a predetermined value according to the first simulation test state point;

[0034] S250), maintaining the first medium in the first medium channel in accordance with the predetermined value supply state of the first simulation test state point of the experiment until the temperature simulation unit enters a stable working state, at which time the total temperature of the second medium passing through the outlet of the second medium channel is the same as the total intake temperature of the engine at the first simulation state point.

[0035] S300), engine intake total pressure regulation

[0036] The engine intake supply pressure regulating valve is adjusted according to the total intake pressure at the first simulated state point, so that the total pressure of the second medium passing through the outlet of the second medium channel is the same as the total intake pressure of the engine at the first simulated state point.

[0037] S400), engine ignition

[0038] The engine fuel supply flow regulating valve is adjusted according to the fuel demand at the first simulation state point of the engine, so that the fuel supplied by the fuel supply source is the same as the fuel demand at the first simulation state point of the engine. The engine is ignited, and the intake simulation test at the first simulation state point is performed until the intake simulation test at this state point ends.

[0039] S500), simulation test of the Nth simulation state point

[0040] The oxygen supply flow regulating valve, the engine intake supply pressure regulating valve, the alcohol supply flow regulating valve and the engine fuel supply flow regulating valve are respectively adjusted to make the total pressure, total temperature and oxygen content of the second medium at the outlet of the second medium channel the same as the intake total pressure, total temperature and oxygen content of the engine at the Nth simulation state point, and the fuel supplied by the fuel supply source is the same as the fuel demand of the engine at the Nth simulation state point; wherein, N≥2, and the intake simulation test of the engine at the Nth state point is started and ended.

[0041] S510), adjusting the oxygen supply flow regulating valve so that the oxygen content of the second medium at the outlet of the second medium channel is the same as the oxygen content of the engine at the Nth simulation state point;

[0042] S520), according to the total temperature of the second medium at the outlet of the second medium channel, the mass of the second medium in the second medium channel, the constant pressure specific heat of the second medium, the convection heat transfer coefficient of the outer wall of the tube body, the inner wall area of ​​the entire tube body, the mass of the first medium in the first medium channel, the constant pressure specific heat of the first medium, the convection heat transfer coefficient of the outer wall of the tube body, the outer wall area of ​​the entire tube body, and the total temperature of the second medium at the inlet of the second medium channel at the Nth simulation state point;

[0043] S530), adjusting the alcohol supply flow regulating valve to adjust the first medium state in the first medium channel from the predetermined value supply at the first simulation test state point to the predetermined value supply at the Nth simulation test state point;

[0044] S540), maintaining the first medium in the first medium channel in accordance with the predetermined value of the Nth simulation test state point of the experiment until the temperature simulation unit enters a stable working state, at which time the total temperature of the second medium passing through the outlet of the second medium channel is the same as the total intake temperature of the engine at the Nth simulation state point;

[0045] S550), adjusting the engine intake supply pressure regulating valve according to the intake total pressure at the Nth simulation state point, so that the total pressure of the second medium passing through the outlet of the second medium channel is the same as the intake total pressure of the engine at the Nth simulation state point;

[0046] S560), adjusting the engine fuel supply flow regulating valve according to the fuel demand of the engine at the Nth simulation state point, so that the fuel supplied by the fuel supply source is the same as the fuel demand of the engine at the Nth simulation state point, and starting the intake simulation test of the engine at the Nth state point until the intake simulation test at this state point ends.

[0047] S600), repeat step S500 until all simulation state points are tested, the engine is turned off, and the engine fuel supply flow regulating valve, oxygen supply flow regulating valve, engine intake supply pressure regulating valve and alcohol supply flow regulating valve are closed.

[0048] Preferably, the highest operating condition value that the temperature simulation unit can withstand is the highest pressure, highest temperature and highest flow rate of the first medium that the temperature simulation unit can withstand; the parameters of the predetermined values ​​of the simulation test state point include the pressure of the medium inlet and outlet, the medium flow rate and the medium temperature.

[0049] Preferably, in step S220, the state of step S210 is maintained until the temperature simulation unit enters a stable working state, and the time required is T1; in step S250, the first medium in the first medium channel is maintained in a supply state according to a predetermined value of the first simulation test state point of the experiment until the temperature simulation unit enters a stable working state, and the time required is T2; in step S540, the first medium in the first medium channel is maintained in a supply state according to a predetermined value of the Nth simulation test state point of the experiment until the temperature simulation unit enters a stable working state, and the time required is T N ;

[0050] T1, T2 and T N All are determined according to the calculation formula for the temperature simulation unit to enter a stable working state; the calculation formula for the temperature simulation unit to enter a stable working state is:

[0051]

[0052] Where: T x is the time for the temperature simulation unit to enter a stable working state, in seconds; m is the mass of the entire pipe, in kg, which is a known quantity; c mp is the constant pressure specific heat of the tube, in J / kg·K, which is a known quantity; h h is the convection heat transfer coefficient of the inner wall of the tube, in W / (m 2 K), is a known quantity; A si is the inner wall area of ​​the entire tube, in m 2 , is a known quantity; m h is the mass of the first medium in the first medium channel, in kg, which is a known quantity; c ph is the constant pressure specific heat of the first medium, in J / kg·K, which is a known quantity; h c is the convective heat transfer coefficient of the outer wall of the tube, in W / (m 2 K), is a known quantity; A se is the outer wall area of ​​the entire tube, in m 2 , is a known quantity; m cis the mass of the second medium in the second medium channel, in kg, which is a known quantity; c pc is the constant-pressure specific heat of the second medium, in J / kg·K, which is a known quantity.

[0053] Preferably, step S230 determines the supply temperature of the first medium according to the total temperature of the second medium at the outlet of the second medium channel, the mass of the second medium in the second medium channel, the constant pressure specific heat of the second medium, the convection heat transfer coefficient of the inner wall of the tube body, the inner wall area of ​​the entire tube body, the mass of the first medium in the first medium channel, the constant pressure specific heat of the first medium, the convection heat transfer coefficient of the outer wall of the tube body, the outer wall area of ​​the entire tube body and the total temperature of the second medium at the inlet of the second medium channel at the first simulation state point. At this time, the supply temperature of the first medium is T hi1 ;

[0054] In step S520, the supply temperature of the first medium is determined according to the total temperature of the second medium at the outlet of the second medium channel, the mass of the second medium in the second medium channel, the constant pressure specific heat of the second medium, the convection heat transfer coefficient of the inner wall of the tube body, the inner wall area of ​​the entire tube body, the mass of the first medium in the first medium channel, the constant pressure specific heat of the first medium, the convection heat transfer coefficient of the outer wall of the tube body, the outer wall area of ​​the entire tube body, and the total temperature of the second medium at the inlet of the second medium channel at the Nth simulation state point. At this time, the supply temperature of the first medium is T hiN ;

[0055] T hi1 and T hiN All are determined according to the temperature simulation unit heat flow input temperature formula; the temperature simulation unit heat flow input temperature formula is:

[0056]

[0057] Where:

[0058] T hix is the supply temperature of the first medium, in K; T co is the total temperature of the second medium at the outlet of the second medium channel, in K, which is a known quantity; m c is the mass of the second medium in the two-medium channel, in kg, which is a known quantity; c pc is the constant pressure specific heat of the second medium, in J / kg·K, which is a known quantity; h h is the convection heat transfer coefficient of the inner wall of the tube, in W / (m 2 K), is a known quantity; A si is the inner wall area of ​​the entire tube, in m 2 , is a known quantity; m h is the mass of the first medium in the first medium channel, in kg, which is a known quantity; c phis the constant pressure specific heat of the first medium, in J / kg·K, which is a known quantity; h c is the convective heat transfer coefficient of the outer wall of the tube, in W / (m 2 K), is a known quantity; A se is the outer wall area of ​​the entire tube, in m 2 , is a known quantity; T ci is the total temperature of the second medium at the inlet of the second medium channel, in K, which is a known quantity.

[0059] Preferably, when conducting an engine intake simulation test, the engine under test is at the ambient pressure of the flight altitude, and an exhaust device can be used to extract the pressure in the simulation cabin. Preferably, the exhaust device is a vacuum tank or an ejector.

[0060] In addition to the beneficial technical effects mentioned above, the engine test bench air intake system of the present invention has the following beneficial technical effects:

[0061] 1. The method of first adjusting the total intake pressure and oxygen content, then adjusting the total intake temperature, and then fine-tuning the total intake pressure before fuel supply and ignition is adopted. The adjustment speed is fast, which saves the adjustment time of the test bench engine intake simulation, reduces the test cost, and avoids energy waste.

[0062] 2. During the use of the temperature simulation unit, creatively, at startup, first use the highest operating value that the temperature simulation unit can withstand to input hot air flow into the heat exchanger, so that the inner tube of the temperature simulation unit works at full load and heats up at the fastest speed. The tube temperature rises quickly and the temperature distribution is uniform. Then, it is adjusted from the full load state to the preset test value, and the time to enter the stable working state is greatly shortened.

[0063] 3. During the use of the temperature simulation unit, a high-accuracy calculation formula for the temperature simulation unit to enter a stable working state was determined through a large amount of test data and creative data curve fitting. This can accurately determine the time when the temperature simulation unit enters a stable working state, greatly shorten the test time, reduce the test cost, and avoid energy waste.

[0064] 4. During the use of the temperature simulation unit, a high-accuracy heat flow input calculation formula for the temperature simulation unit was determined through a large amount of test data and creative data curve fitting. The heat flow input temperature of the temperature simulation unit can be accurately determined, which greatly shortens the test time, reduces the test cost, and avoids energy waste.

[0065] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0066] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A method for using an intake system of an engine test bench, characterized in that: It includes a supply source, a temperature simulation unit and a simulation chamber; The supply source includes a fuel supply source, an oxygen supply source, an engine intake air supply source and an alcohol supply source; The temperature simulation unit includes a tube body and a shell, the tube body is located inside the shell, the tube body is a first medium channel, and the space between the outer wall of the tube body and the inner wall of the shell forms a second medium channel; The engine under test is located in the simulation cabin; The fuel supply source is connected to the tested engine through a pipeline, the oxygen supply source and the engine intake supply source are connected to the inlet of the second medium channel through pipelines respectively, the outlet of the second medium channel is connected to the intake port of the tested engine through a pipeline, and the alcohol supply source is connected to the inlet of the first medium channel through a pipeline after passing through the igniter; An engine fuel supply flow regulating valve and an engine fuel supply stop valve are provided on the pipeline connecting the fuel supply source and the tested engine; an oxygen supply flow regulating valve and an oxygen supply stop valve are provided on the pipeline connecting the oxygen supply source and the inlet of the second medium channel; an engine intake supply pressure regulating valve is provided on the pipeline connecting the engine intake supply source and the inlet of the second medium channel; an alcohol supply flow regulating valve and an alcohol supply stop valve are provided on the pipeline connecting the alcohol supply source and the inlet of the first medium channel, and the outlet of the first medium channel is connected to the outside; The method for using the air intake system of the engine test bench includes the following steps: S100), engine intake total pressure and oxygen content regulation According to the total intake pressure and oxygen content at the first simulation state point, the engine intake supply pressure regulating valve and the oxygen supply flow regulating valve are adjusted to make the total pressure and oxygen content of the second medium passing through the outlet of the second medium channel the same as the total intake pressure and oxygen content of the engine at the first simulation state point; S200), engine intake total temperature regulation According to the total intake air temperature at the first simulation state point, the alcohol supply flow regulating valve is adjusted and the igniter is started to ignite the alcohol to burn the alcohol. The burning alcohol exchanges heat with the second medium in the second medium channel in the first medium channel, so that the total temperature of the second medium passing through the outlet of the second medium channel is the same as the total intake air temperature of the engine at the first simulation state point; S210), adjusting the alcohol supply flow regulating valve according to the highest operating value that the temperature simulation unit can withstand, starting the igniter, igniting the alcohol to make it burn, and the burning alcohol exchanges heat with the second medium in the first medium channel and the second medium channel; S220), maintaining the state of step S210 until the temperature simulation unit enters a stable working state; S230), according to the total temperature of the second medium at the outlet of the second medium channel, the mass of the second medium in the second medium channel, the constant pressure specific heat of the second medium, the convection heat transfer coefficient of the outer wall of the tube body, the inner wall area of ​​the entire tube body, the mass of the first medium in the first medium channel, the constant pressure specific heat of the first medium, the convection heat transfer coefficient of the outer wall of the tube body, the outer wall area of ​​the entire tube body, and the total temperature of the second medium at the inlet of the second medium channel at the first simulation state point; S240), adjusting the alcohol supply flow regulating valve to adjust the state of the first medium in the first medium channel from the highest operating value that the temperature simulation unit can withstand to a predetermined value according to the first simulation test state point; S250), maintaining the first medium in the first medium channel in accordance with the predetermined value of the first simulation test state point of the experiment until the temperature simulation unit enters a stable working state, at which time the total temperature of the second medium passing through the outlet of the second medium channel is the same as the total intake air temperature of the engine at the first simulation state point; S300), engine intake total pressure regulation According to the total intake pressure at the first simulation state point, the engine intake supply pressure regulating valve is adjusted so that the total pressure of the second medium passing through the outlet of the second medium channel is the same as the total intake pressure of the engine at the first simulation state point; S400), engine ignition According to the fuel demand of the first simulation state point of the engine, the engine fuel supply flow regulating valve is adjusted so that the fuel supplied by the fuel supply source is the same as the fuel demand of the first simulation state point of the engine, the engine is ignited, and the intake simulation test of the first simulation state point is performed until the intake simulation test of the state point is completed; S500), simulation test of the Nth simulation state point.

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