A test bench for testing heavy oil air injection system

Abstract

The present invention provides a test bench for testing a heavy oil direct injection system with air, comprising a test bench body, a transmission system, an air supply system, an oil supply system, a data acquisition and testing device, a fuel metering device, an ECU control system, and a computer host. The test bench body is used to fix the test system of the direct injection system with air. The transmission system provides different rotation speeds to simulate the engine speed. The air supply system provides a stable intake pressure for the compressor, and can also adjust the intake pressure to simulate the intake pressure of the engine under different environments. The oil supply system provides fuel with stable pressure for the direct injection system with air. The data acquisition and testing device is used to collect various performance parameters of the direct injection system with air. The computer host is connected to the injector of the direct injection system with air through the ECU control system and the communication line to monitor the status of the direct injection system with air in real time.

Description

Technical Field

[0001] The invention relates to a test bench for testing a heavy oil air-entrained direct injection system, belonging to the technical field of engine component testing. Background Art

[0002] In recent years, the investment in the development and procurement of UAVs has shown explosive growth. Although the current mainstream aircraft power mainly adopts gas turbines (turboshaft, turbojet, turboprop), the advantages of piston engines in terms of economy and easy maintenance have always made it occupy a place in the world's aviation field. Especially in terms of UAVs with a take-off weight of less than one ton, piston UAVs have an absolute advantage in quantity. As the military has higher and higher requirements for fuel safety, strict requirements are put forward for the fuel of UAV piston engines. Heavy oil has obvious advantages over gasoline: high safety, can meet the military's fuel integration requirements, simplify troop logistics support, and improve support efficiency. Aviation heavy oil piston engines have become an urgent need for the construction of small and medium-sized long-flight UAV equipment and small general-purpose aircraft.

[0003] Due to the problems of high kinematic viscosity, poor volatility, and poor atomization of heavy oil fuel, which directly affect the engine combustion efficiency and cold start performance, it is difficult for ordinary injection systems to make heavy oil form a mixture that can meet the combustion in the cylinder. The air-entrained direct injection system premixes the fuel with compressed air, and then the oil-gas mixture is sprayed into the cylinder at high speed by the direct injection nozzle, and the fuel is atomized into extremely fine droplets at high speed and evaporates rapidly. On the one hand, it greatly reduces the requirements of the engine for the fuel system, and on the other hand, it makes the spray diffusion mixing process faster. The air-entrained direct injection system has been widely used in the field of two-stroke UAV heavy oil engines. The air-entrained direct injection system can enable heavy oil fuels such as aviation kerosene and diesel to be ignited and burned, avoiding the disadvantage of the low power-to-weight ratio of traditional compression ignition engines. It can meet the current power-to-weight ratio requirements of UAVs for heavy oil engines, and at the same time solve the demand for heavy oil fuel for UAVs.

[0004] During the design and development of the heavy oil air injection system, it is necessary to test the sample on a special test bench to understand the various performances of the air injection system. Therefore, it is necessary to develop a test bench suitable for the heavy oil air injection system. Summary of the invention

[0005] The purpose of the present invention is to provide a test bench for testing a heavy oil air-entrained direct injection system, which is suitable for various performance tests of the air-entrained direct injection system.

[0006] The embodiment of the present invention provides a test bench for testing a heavy oil air-injection system, including a test bench body, a transmission system, an air supply system, an oil supply system, a data acquisition and testing device, a fuel metering device, an ECU control system, and a computer host. The test bench body includes a cabinet frame, a compressor, a compressor fixing seat, an injector mounting base, a measuring cylinder mounting base, and an air-injection system. The compressor fixing seat, the injector mounting base, and the measuring cylinder mounting base are fixed on the cabinet frame, the compressor is fixed on the compressor fixing seat, and the air-injection system is fixed on the injector mounting base. The transmission system includes a motor and a coupling, wherein the motor is connected to the eccentric drive shaft of the compressor through a coupling, and is used to drive the compressor to operate stably, and the motor provides different speeds to simulate the engine speed. The air supply system includes an air filter, a barometer, and an air compressor. The air compressor is connected to the barometer, the air filter, and the compressor through an intake pipeline to provide a stable intake pressure for the compressor, and the intake pressure can also be adjusted to simulate the intake pressure of the engine under different environments. The fuel supply system includes a fuel tank and a fuel pump. The fuel pump is connected to the air-injection system through a high-pressure oil pipe to provide the air-injection system with fuel of stable pressure. The data acquisition and testing device includes a pressure sensor and a pressure mechanical gauge installed on the air-injection system and the fuel pump. The pressure sensor is used to measure the air supply pressure and injection pressure of the air-injection system. The pressure mechanical gauge can be used for real-time calibration of the pressure sensor to ensure the accuracy of the pressure sensor test data. The fuel metering device includes a measuring cylinder and an electronic scale for measuring the measuring cylinder, which are used to measure the injection volume of the air-injection system. The computer host is connected to the injector of the air-injection system through the ECU control system and the communication line to monitor the status of the air-injection system in real time.

[0007] Furthermore, the cabinet frame is formed by connecting aluminum profiles and their attached corner pieces, and the whole is a rectangular structure divided into two layers, upper and lower layers.

[0008] Furthermore, the compressor is a piston compressor, which is provided with an eccentric drive shaft, a pressure sensor, an air inlet, and an air supply port. The air inlet is connected to the air compressor through the air supply pipeline, and the air supply port is connected to the air-entrained direct injection system through the air supply pipeline.

[0009] Furthermore, the compressor fixing seat is an integrated centering structure, which is divided into left and right fixing seats, one end of which is equipped with the compressor, and the other end is equipped with the motor, and the compressor and the motor are directly connected to the eccentric drive shaft of the compressor through the coupling.

[0010] Furthermore, the data acquisition and testing device is equipped with a pressure mechanical meter, which can be used for real-time calibration of the pressure sensor to ensure the accuracy of the data collected by the pressure sensor.

[0011] Furthermore, the air compressor is an additional auxiliary air supply device, which provides a stable pressure air source for the compressor intake.

[0012] Furthermore, the injector mounting base is an I-shaped device with a plurality of mounting holes preset thereon, which can satisfy the installation and testing of a single injector or two injectors at the same time. In addition, four key slots are preset on the four supporting feet to connect with the measuring cylinder mounting base, and are fixed to the middle plate of the cabinet frame through the bottom mounting holes.

[0013] Furthermore, the coupling is an aluminum alloy diaphragm coupling with a keyway at one end.

[0014] Furthermore, the measuring cylinder mounting base is used to mount the measuring cylinder, and is a rectangular bottom plate with four raised iron sheets arranged around it, on which four mounting holes are preset, and the four mounting holes are respectively connected to the key slots on the injector mounting base to adjust the height of the measuring cylinder position.

[0015] Furthermore, the fuel tank is a rectangular tank with a volume of about 10L, on which a fuel inlet and a fuel return port are preset, which are respectively connected to the fuel inlet of the fuel pump and the fuel inlet and fuel outlet of the air injection system through a high-pressure fuel pipe and a return oil pipeline.

[0016] The beneficial effects of the present invention are:

[0017] (1) The present invention provides a test bench for testing a heavy oil direct injection system with air, which is designed with a piston compressor structure and can perform air supply performance tests under different displacements, providing a design basis for the air supply system of the direct injection system with air.

[0018] (2) The present invention designs an air supply system mounting base, which adopts a left and right fixed seat structure. The mutual cooperation of the left and right fixed seats can achieve a more ideal alignment, reduce the vibration during the operation of the air supply system, and achieve smoother transmission to ensure the stability of the air supply pressure.

[0019] (3) The present invention designs an injector mounting base, which is pre-designed with multiple mounting holes, so that one or more injectors can be installed at the same time without interfering with each other, and can be used to simulate the performance of a multi-cylinder engine air injection system.

[0020] (4) The present invention designs a measuring cylinder mounting base, which can adjust the distance between the measuring cylinder and the injector. High-precision measuring cylinders of different ranges can be replaced to adapt to injectors of different working conditions, thereby completing the test of the flow characteristics of the air-entrained direct injection system. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 A schematic diagram of a test bench for testing a heavy oil-air direct injection system proposed in an embodiment of the present invention.

[0022] In the figure:

[0023] 1—electronic scale, 2—ECU control system, 3—middle plate, 4—measuring cylinder mounting base, 5—fuel pump, 6—high-pressure oil pipe, 7—pressure mechanical gauge, 8—injector mounting base, 9—air clamp direct injection system, 10—cabinet frame, 11—pressure sensor, 12—compressor, 13—air supply pipeline, 14—coupling, 15—motor, 16—compressor fixing base, 17—air pressure gauge, 18—air filter, 19—air compressor, 20—fuel tank, 21—return oil pipeline, 22—computer host, 23—communication line, 24—measuring cylinder, 25—universal wheel, 26—fuel filter. DETAILED DESCRIPTION

[0024] The present invention will be further described below in conjunction with the accompanying drawings:

[0025] Reference Figure 1The embodiment of the present invention provides a test bench for testing a heavy oil air injection system, including a test bench body, a transmission system, an air supply system, an oil supply system, a data acquisition and testing device, a fuel metering device, an ECU control system 2, and a computer host 22. The test bench body includes a cabinet frame 10, a universal wheel 25, a compressor 12, an air injection system 9, a compressor fixing seat 16, an injector mounting base 8, and a measuring cylinder mounting base 4. The cabinet frame 10 is assembled by connecting aluminum profiles and angle pieces, and is divided into two layers, an upper layer and a lower layer, with an intermediate plate 3 arranged in the middle, and a universal wheel 25 is installed at the bottom to contact the ground. The universal wheel structure facilitates the movement and fixation of the entire test bench. The compressor fixing seat 16, the injector mounting base 8, and the measuring cylinder mounting base 4 are all fixed on the intermediate plate 3 in the cabinet frame 10, and the compressor 12 is fixed on the compressor fixing seat 16. The air injection system mainly includes an injector, which is fixed on the injector mounting base 3. The transmission system includes a motor 15 and a coupling 14. The motor 15 is fixed on a compressor fixing seat 16. The motor 15 is connected to the drive shaft of the compressor 12 through the coupling 14. The air supply system includes an air filter 18, a barometer 17 and an air compressor 19, which are connected to the air inlet of the compressor 12 through an air supply pipeline 13. The oil supply system includes a fuel tank 20 and a fuel pump 5, which are connected to the air injection system 9 through a high-pressure oil pipe 6 and a return oil pipeline 21. The data acquisition and testing device includes a pressure sensor 11 and a pressure mechanical gauge 7 installed on the air injection system and the fuel pump, which are respectively fixed on the air injection system 9 and the fuel pump 5. The fuel metering device includes a measuring cylinder 24 and an electronic scale 1. The measuring cylinder 24 is fixed on the measuring cylinder mounting base 4 and is used to measure the injection amount of the air injection system. The host computer 22 is connected to the ECU control system 2, the air-entrained direct injection system 9 installed on the injector mounting base 8, and the electronic scale 1 through the communication line 23 to monitor the state of the air-entrained direct injection system in real time.

[0026] The present invention provides a compressor and a compressor mounting base, which are divided into left and right fixed bases. The mutual cooperation of the left and right fixed bases can achieve more ideal alignment, and the vibration generated by themselves will be weakened, so that more ideal transmission can be achieved, which is closer to the engine working condition, thereby achieving the stability of the air supply pressure; the injector mounting base is preset with multiple hole positions, which can realize the installation of one or more injectors at the same time without interfering with each other, and is suitable for the installation of different types of injectors; the distance between the measuring cylinder and the fuel injector can be adjusted by the measuring cylinder mounting base, and high-precision measuring cylinders of different ranges can be replaced to adapt to fuel injectors of different working conditions, which are mainly used to collect the oil sprayed by the injector, detect the detection liquid through the fuel metering device, and finally filter it through the collecting device for reuse; the oil pressure and air pressure of the air-entrained direct injection system are accurately collected by the pressure sensors on the air-entrained direct injection system and the compressor, thereby achieving higher measurement accuracy.

[0027] Preferably, the cabinet frame 10 is divided into two layers, the upper and lower layers, which are assembled from a plurality of aluminum profiles supplemented by corresponding connecting corner pieces, wherein the cabinet frame 10 further includes four universal wheels 25, and the universal wheels 25 are both positionable and movable.

[0028] Preferably, a pressure sensor 11 is provided on the outer wall of the compressor 12, and the pressure sensor 11 is connected to a computer host 22. The computer host 22 collects pressure values ​​through the pressure sensor 11 and collects the intake pressure of the compressor in real time.

[0029] Preferably, a pressure mechanical meter 7 is provided in the oil supply pipeline, and the pressure mechanical meter can be used for real-time calibration of the pressure sensor 11 to ensure the accuracy of the test data of the pressure sensor 11.

[0030] Preferably, compressor mounting holes and motor mounting holes are respectively provided at both ends of the compressor fixing seat 16. The compressor 12 is connected to the motor 15 via a coupling 14. The coaxiality of the compressor and the motor is ensured through integrated machining.

[0031] Preferably, the compressor 12 adopts a piston structure, and the piston is driven by designing an eccentric shaft and a needle bearing structure on the crankshaft. The stable air source is provided by the air compressor 19, and then passes through the compressor 12 to form a high-pressure air, and then enters the air-injection direct injection system 9 through the air supply pipeline 13. The compressor cylinder adopts a split structure. This structure can change the displacement or compression ratio of the compressor by replacing the eccentric shaft or cylinder body of the compressor 12, and carry out air supply performance tests of air-injection direct injection engines with different displacements.

[0032] Preferably, the air-entrained direct injection system 9 is installed on an injector mounting base 8, the air inlet at the air rail end is connected to the compressor 12 through an air supply pipeline 13, the oil inlet at the oil rail end is connected to the fuel pump 5 through a high-pressure oil pipe 6, the oil return port is connected to the fuel tank 20 through an oil return pipeline 21, the threaded port is connected to the pressure sensor 11, the pressure sensor 11 is connected to a computer host 22, the computer host 22 collects the pressure value through the pressure sensor 11, and the injection pressure of the air-entrained direct injection system can be measured by real-time monitoring of the pressure value in the oil rail.

[0033] Preferably, the fuel pump 5 adopts a magnetically driven gear pump with adjustable speed and pressure, and is provided with an oil inlet, an oil outlet and a pressure gauge. The oil inlet is connected to the fuel tank 20 through a fuel filter 26 and a high-pressure oil pipe 6, and the oil outlet is connected to the oil inlet of the air-entrained direct injection system 9 through the high-pressure oil pipe 6. By adjusting the oil supply pressure of the fuel pump 5, the test requirements of different injection pressures of the air-entrained direct injection system can be met, which provides a basis for the design optimization of the injector in the air-entrained direct injection system, thereby broadening the scope of use of the measuring device and improving the versatility.

[0034] Preferably, the fuel metering device includes a measuring cylinder 24 and an electronic scale 1. The measuring cylinder 24 is installed through the measuring cylinder mounting base 4, and the height is adjusted so that the measuring cylinder 24 is located at a suitable position below the injector. When the test is started, the measuring cylinder 24 can complete the collection of the injection amount. After the test is completed, it is placed on the electronic scale 1 for weighing after being left to stand for a period of time. This cycle can be repeated multiple times to take the average value, thereby accurately collecting the injection amount and improving the measurement accuracy of the injection amount of the air-entrained direct injection system.

[0035] In summary, the present invention aims to protect a test bench for testing a heavy oil air injection system, including a test bench body, a transmission system, an air supply system, an oil supply system, a data acquisition and testing device, a fuel metering device, an ECU control system, and a computer host. The test bench body includes a cabinet frame, a compressor, a compressor fixing seat, an injector mounting base, a measuring cylinder mounting base, and an air injection system. The compressor fixing seat, the injector mounting base, and the measuring cylinder mounting base are fixed on the cabinet frame, the compressor is fixed on the compressor fixing seat, and the air injection system is fixed on the injector mounting base. The transmission system includes a motor and a coupling, wherein the motor is connected to the eccentric drive shaft of the compressor through a coupling, and is used to drive the compressor to operate stably, and the motor provides different speeds to simulate the engine speed. The air supply system includes an air filter, a barometer, and an air compressor. The air compressor is connected to the barometer, the air filter, and the compressor through an intake pipeline to provide a stable intake pressure for the compressor, and the intake pressure can also be adjusted to simulate the intake pressure of the engine under different environments. The fuel supply system includes a fuel tank and a fuel pump. The fuel pump is connected to the air-injection system through a high-pressure oil pipe to provide the air-injection system with fuel of stable pressure. The data acquisition and testing device includes a pressure sensor and a pressure mechanical gauge installed on the air-injection system and the fuel pump. The pressure sensor is used to measure the air supply pressure and injection pressure of the air-injection system. The pressure mechanical gauge can be used for real-time calibration of the pressure sensor to ensure the accuracy of the pressure sensor test data. The fuel metering device includes a measuring cylinder and an electronic scale for measuring the measuring cylinder, which are used to measure the injection volume of the air-injection system. The computer host is connected to the injector of the air-injection system through the ECU control system and the communication line to monitor the status of the air-injection system in real time.

[0036] It should be understood that the above specific embodiments of the present invention are only used to illustrate or explain the principles of the present invention, and do not constitute a limitation of the present invention. Therefore, any modifications, equivalent substitutions, improvements, etc. made without departing from the spirit and scope of the present invention should be included in the protection scope of the present invention. In addition, the appended claims of the present invention are intended to cover all changes and modifications that fall within the scope and boundaries of the appended claims, or the equivalent forms of such scope and boundaries.

Claims

1. A test bench for testing a heavy oil air injection system, comprising a test bench body, a transmission system, an air supply system, an oil supply system, a data acquisition and testing device, a fuel metering device, an ECU control system (2), and a computer host (22). The test bench body comprises a cabinet frame (10), a universal wheel (25), a compressor (12), an air injection system (9), a compressor fixing seat (16), an injector mounting base (8), and a measuring cylinder mounting base (4). The cabinet frame (10) is made of aluminum profiles and angles. The components are connected and assembled, and are divided into two layers, an upper layer and an lower layer, with an intermediate plate (3) arranged in the middle, and a universal wheel (25) is installed at the bottom to contact the ground, the compressor fixing seat (16), the ejector mounting base (8) and the measuring cylinder mounting base (4) are all fixed on the intermediate plate (3) in the cabinet frame (10), the compressor (12) is fixed on the compressor fixing seat (16), the air injection direct injection system (9) is fixed on the ejector mounting base (8), and the transmission system includes a motor (15) and a coupling (14), and the motor (15) is fixed The motor (15) is fixed on a compressor fixing seat (16), and is connected to a drive shaft of the compressor (12) through a coupling (14). The air supply system includes an air filter (18), a pressure gauge (17) and an air compressor (19), and is connected to an air inlet of the compressor (12) through an air supply pipeline (13). The oil supply system includes a fuel tank (20) and a fuel pump (5), and is connected to an air injection system (9) through a high-pressure oil pipe (6), a fuel filter (26) and an oil return pipeline (21). The data acquisition and testing device The invention comprises a pressure sensor (11) and a pressure mechanical gauge (7) installed on the air injection system and the fuel pump, which are respectively fixed on the air injection system (9) and the fuel pump (5); the fuel metering device comprises a measuring cylinder (24) and an electronic scale (1); the measuring cylinder (24) is fixed on a measuring cylinder mounting base (4); the computer host (22) is respectively connected to the ECU control system (2) and the air injection system (9) installed on the injector mounting base (8) and the electronic scale (1) through a communication line (23).

2. The test bench for testing a heavy oil mixed with air direct injection system according to claim 1 is characterized in that: The cabinet frame (10) is formed by connecting aluminum profiles and their attached corner pieces, and is a rectangular structure as a whole, divided into two layers, upper and lower.

3. The test bench for testing a heavy oil-air direct injection system according to claim 1 is characterized in that: The compressor (12) is a piston compressor, which is provided with an eccentric drive shaft, a pressure sensor (11), an air inlet, and an air supply port. The air inlet is connected to the air compressor (19) through the air supply pipeline (13), and the air supply port is connected to the air inlet of the air-entrained direct injection system (9) through the air supply pipeline (13). The eccentric drive shaft of the compressor is connected to the motor (15) through the coupling (14), and the compressor (12) is installed on the left end of the compressor fixing seat (16) through the installation hole.

4. The test bench for testing a heavy oil-air direct injection system according to claim 1 is characterized in that: The compressor fixing seat (16) is an integrated centering structure, which is divided into left and right fixing seats, one end of which is equipped with the compressor (12) and the other end is equipped with the motor (15). The compressor (12) and the motor (15) are directly connected to the eccentric drive shaft of the compressor through the coupling (14).

5. The test bench for testing a heavy oil air injection system according to claim 1 is characterized in that: The air-entrained direct injection system (9) is installed on an injector mounting base (8); the air inlet at the air rail end is connected to the compressor (12) via an air supply pipeline (13); the oil inlet at the oil rail end is connected to the fuel pump (5) via a high-pressure oil pipe (6); the oil return port is connected to the fuel tank (20) via an oil return pipeline (21); the threaded port is connected to a pressure sensor (11); the pressure sensor (11) is connected to a computer host (22); and the computer host (22) collects pressure values ​​via the pressure sensor (11).

6. The test bench for testing a heavy oil-air direct injection system according to claim 1 is characterized in that: The measuring cylinder mounting base (4) is used to mount the measuring cylinder (24), and is a rectangular bottom plate with four raised iron sheets arranged around it. Four mounting holes are preset on it, and the four mounting holes are respectively connected to the key slots on the injector mounting base (8) to adjust the height of the measuring cylinder position.

7. The test bench for testing a heavy oil mixed with air direct injection system according to claim 1 is characterized in that The pressure mechanical meter (7) is installed in the oil supply pipeline and can be used for real-time calibration of the pressure sensor (11) to ensure the accuracy of the test data of the pressure sensor (11).

8. The test bench for testing a heavy oil air injection system according to claim 1 is characterized in that: The injector mounting base (8) is an I-shaped device with a plurality of mounting holes preset thereon, which can meet the requirements of a single injector or two injectors being installed and tested simultaneously. In addition, four key slots are preset on its four supporting feet to be connected to the measuring cylinder mounting base (4) and fixed to the middle plate of the cabinet frame (10) through the bottom mounting holes.

9. The test bench for testing a heavy oil air injection system according to claim 1, characterized in that: The fuel tank (20) is a rectangular fuel tank with a volume of about 10L. It is pre-set with an oil outlet and an oil return port, and is connected to the oil inlet of the fuel pump (5) and the oil outlet of the air injection direct injection system (9) through a high-pressure oil pipe (6) and an oil return pipeline (21).

10. The test bench for testing a heavy oil-air direct injection system according to claim 1, characterized in that: The fuel pump (5) is a magnetically driven gear pump with adjustable speed and pressure, and is provided with an oil inlet and an oil outlet. The oil inlet is connected to the oil outlet of the fuel tank (20) through a high-pressure oil pipe (6), and the oil outlet is connected to the oil inlet of the air injection system (9) through the high-pressure oil pipe (6). The fuel pump (5) is fixed to the middle plate of the cabinet frame (10) through a mounting hole.

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