A test device and method for variable angle jet atomization and combustion of multi-injector fuel injectors in engines

Abstract

This invention discloses a test device and method for variable angle jet atomization and combustion of multi-injector fuel in engines. The invention uses a constant-volume combustion bomb with a cylindrical inner wall to ensure matching with the geometry of the engine cylinder, thus better simulating the spray and combustion characteristics of the engine fuel jet. This allows the test results to be better applied to internal combustion engines in vehicles and ships. Replacing the injector / injection valve and its matching injector end cap enables the testing and analysis of the spray and combustion characteristics of multiple green fuels. By replacing the injector at different windows, multiple identical ignition fuels can be used to ignite one main fuel, one ignition fuel can ignite multiple identical main fuels, and multiple identical ignition fuels can ignite multiple identical main fuels. Observation windows or injector end caps are used at the windows to achieve different functions of observation or fuel injection, thereby testing the spray jet and combustion characteristics at 90° and 180° angles.

Description

Technical Field

[0001] This invention belongs to the field of power and energy engineering, and specifically relates to a test device and method for variable angle jet atomization and combustion of multi-injector fuel injectors in engines. Background Technology

[0002] The internal combustion engine, as a common power unit, boasts advantages such as good fuel economy, high thermal efficiency, large torque, durability, and fuel economy. It is currently widely used in aerospace, transportation, and other fields. Since its inception, the internal combustion engine has been continuously updated and optimized in pursuit of superior power and economy.

[0003] With the iterative development of internal combustion engine technology and increasingly stringent global emission standards, internal combustion engines are constantly evolving towards higher efficiency and cleaner performance. While various technologies exist to reduce the energy consumption and emissions of internal combustion engines, the results achieved by adjusting parameters in the engine's structure and operation are limited. Therefore, ultimately, methods to achieve energy conservation and emission reduction must be sought from the fuels used in internal combustion engines. Increasingly stringent carbon dioxide emission regulations are driving the use of more green, low-carbon / zero-carbon fuels in future internal combustion engines. Therefore, it is urgent to test the spray and combustion characteristics of different green, low-carbon / zero-carbon fuels in internal combustion engines. Low-carbon / zero-carbon fuels include bio-methanol, biodiesel, hydrogen, and ammonia. Due to their different physicochemical properties, different fuels require different injector specifications in internal combustion engines. Therefore, to facilitate the measurement of the spray and combustion characteristics of different fuels in the same testing device, the testing device must be compatible with different injector specifications. However, due to the problems such as difficulty in ignition, low calorific value, and inability to be applied to existing engine models compared with traditional fuels, research on the spray and combustion characteristics of green carbon fuels in internal combustion engines is extremely important.

[0004] However, due to the poor flammability and low laminar flame velocity of green low / zero carbon fuels such as ammonia, their economic performance is worse than that of pure diesel engines under the same conditions. Therefore, it is necessary to add other green low / zero carbon fuels to activate their chemical properties and assist combustion. Thus, dual-fuel spray and combustion testing is particularly important for energy saving and emission reduction of internal combustion engines. However, there are very few devices that can test the characteristics of low / zero carbon dual-fuel spray and combustion. If the requirement of variable relative positions of different fuel sprays is also met, the existing testing equipment is almost non-existent. Therefore, there is an urgent need for a test device and method for variable angle jet atomization and combustion of multi-injector engines. Summary of the Invention

[0005] The purpose of this invention is to provide a device and method for testing variable angle jet atomization and combustion of multi-injector fuel injectors in engines.

[0006] The objective of this invention is achieved through the following technical solution:

[0007] A simulated engine multi-injector coupled atomization and combustion test device includes a constant volume combustion bomb, an injection valve end cap, an injection valve, a thermocouple, a viewing window end cap, an observation window, a high-pressure air cylinder, an intake valve, a heating device, an exhaust valve (12), an exhaust gas treatment device, an injector, and an injector end cap.

[0008] The inner wall of the constant-volume incendiary bomb is cylindrical, and the outer wall is cubic. The observation window is made of quartz glass, and the quartz glass is connected to the constant-volume incendiary bomb by means of a fixing bolt and an end cap of the window.

[0009] The observation window is the same size as the injector end cap and the injection valve end cap. By replacing the observation window with the injector end cap and the injection valve end cap, the purpose of arranging the injector or injection valve or the observation window at the window position can be achieved.

[0010] The heating device is located at the bottom of the constant-volume incendiary bomb, and the thermocouple is located at the top of the constant-volume incendiary bomb.

[0011] The upper part of the constant-volume incendiary bomb is connected to an exhaust valve and a tail gas treatment device in sequence; the lower part is connected to an air inlet valve and a high-pressure air cylinder in sequence.

[0012] Furthermore, a rubber gasket is used between the observation window and the constant-volume incendiary bomb to ensure the airtightness of the constant-volume incendiary bomb.

[0013] Furthermore, the number of observation windows is up to four.

[0014] Furthermore, the installation position of the heating device does not affect the observation through the viewing window or the operation of the fuel injector or injection valve.

[0015] A method for simulating the coupled atomization and combustion of multiple fuel injectors in an engine is as follows:

[0016] Step 1: Before starting the test device;

[0017] Select the appropriate injection valve and injector based on the required test fuel, and customize the injection valve end cap and injector end cap to match the injection valve and injector respectively.

[0018] Step 2: Start the test;

[0019] Arrange the positions of the injection valve end cap and injector end cap according to the spray angle of the test fuel; determine the fuel injection timing, duration and injection pressure, and regulate them through an external synchronization controller; determine the cylinder pressure and temperature;

[0020] Step 3: Test the fuel jet spray characteristics or jet combustion characteristics;

[0021] (1) If testing fuel jet spray characteristics:

[0022] The temperature inside the constant-volume combustion bomb is adjusted to T1 by the heating device. T1 = the measured cylinder temperature at the operating point minus 20K. The temperature inside the constant-volume combustion bomb is monitored by thermocouples.

[0023] After the temperature inside the constant volume combustion bomb stabilizes, the pressure inside the constant volume combustion bomb is adjusted to P1, which is the pressure at the measured operating point, through the high-pressure air cylinder.

[0024] According to the ideal gas law PV=nRT, the temperature will also increase as the pressure increases. Therefore, when adjusting the pressure, the temperature inside the constant volume combustion bomb gradually approaches the measured operating point temperature.

[0025] After the pressure is adjusted, the heating device is used to adjust the temperature inside the constant volume combustion bomb to T2, which is the measured operating point temperature, and the temperature inside the constant volume combustion bomb is monitored by thermocouples.

[0026] The injection valve is activated, and a high-pressure fuel jet enters the test device;

[0027] The fuel injector starts working, and a high-pressure fuel jet enters the test device;

[0028] Choose any observation window for light intake, and use an optical testing device to record its spray characteristics in the opposite window;

[0029] (2) To test the combustion characteristics of fuel jet:

[0030] Determine the temperature and pressure required for diesel fuel to be compressed and ignited;

[0031] The temperature inside the constant-volume combustion bomb is adjusted to the measured operating point cylinder temperature by the heating device, and the temperature inside the constant-volume combustion bomb is monitored by thermocouples.

[0032] After the temperature inside the cylinder stabilizes, adjust the pressure inside the constant volume combustion bomb to the pressure at the measured operating point using a high-pressure air bottle.

[0033] According to the ideal gas law PV=nRT, the temperature will also increase as the pressure increases. Therefore, when adjusting the pressure, the temperature inside the constant volume combustion bomb gradually approaches the measured operating point temperature.

[0034] After the pressure is adjusted, the heating device is used to adjust the temperature inside the constant volume combustion bomb to T2, which is the measured operating point temperature, and the temperature inside the constant volume combustion bomb is monitored by thermocouples.

[0035] The injection valve is activated, and a high-pressure fuel jet enters the test device;

[0036] The fuel injector starts working, and a high-pressure fuel jet enters the test device;

[0037] By increasing the pressure inside the constant-volume incendiary bomb, it reaches the set value for igniting the compression ignition of the fuel and then burns it.

[0038] Optical testing equipment was set up at one or more windows to record its combustion characteristics.

[0039] Step 4: Combustion ends;

[0040] The intake valve and exhaust valve open simultaneously. Air enters the lower part of the constant volume combustion bomb from the high-pressure air cylinder through the pipeline and is discharged from the top of the constant volume combustion bomb, thereby completing the in-cylinder scavenging. The exhaust gas and air mixture enter the exhaust gas treatment device through the pipeline and is discharged after purification.

[0041] Step 5: Exhaust complete;

[0042] Repeat the above steps to conduct multiple repeatable experiments.

[0043] The beneficial effects of this invention are as follows:

[0044] This invention uses a constant-volume combustion bomb with a cylindrical inner wall to ensure that it matches the geometry of the engine cylinder. This allows for better simulation of the spray and combustion characteristics of the engine fuel jet, enabling the test results to be better applied to internal combustion engines in vehicles and ships.

[0045] This invention enables the testing and analysis of the spray and combustion characteristics of various green fuels by replacing the injector / injection valve and its matching injector end cap.

[0046] This invention enables the testing and analysis of 90° and 180° spray jets and combustion characteristics by replacing the injector end cap and observation window in the window.

[0047] This invention enables multiple identical ignition fuels to ignite one main fuel, one ignition fuel to ignite multiple identical main fuels, and multiple identical ignition fuels to ignite multiple identical main fuels by changing the injectors at different windows.

[0048] In summary, this invention enables the replacement of injectors used for different fuels by changing the injector end cap, and allows the use of an observation window or injector end cap at the window to achieve different functions of observation or fuel injection, thereby testing the spray jet and combustion characteristics at 90° and 180°. Attached Figure Description

[0049] Figure 1 This is a schematic diagram of the structure of a variable angle jet atomization and combustion testing device for engine multi-injector as described in an embodiment of the present invention;

[0050] Figure 2 This is a schematic diagram of a replaceable injector end cap structure for an engine multi-injector variable angle jet atomization and combustion testing device according to an embodiment of the present invention.

[0051] Figure 3 This is a system diagram of a variable angle jet atomization and combustion testing device and method for engine multi-injector as described in an embodiment of the present invention.

[0052] Explanation of reference numerals in the attached figures:

[0053] 1-Constant volume incendiary bomb; 2-Fixing bolt; 3-Ammonia injection valve end cap; 4-Ammonia injection valve; 5-Thermocouple; 6-Viewing window end cap; 7-Rubber gasket; 8-Observation window; 9-High pressure air cylinder; 10-Intake valve; 11-Heating device; 12-Exhaust valve; 13-Exhaust gas treatment device; 14-Diesel injector; 15-Diesel injector end cap. Detailed Implementation

[0054] The present invention will now be further described with reference to the accompanying drawings.

[0055] according to Figure 1-3 The present invention provides a variable angle jet atomization and combustion testing device for engine multi-injector fuel injectors, comprising a constant volume combustion bomb 1, a fixing bolt 2, an injection valve end cap 3, an injection valve 4, a thermocouple 5, a viewing window end cap 6, a rubber gasket 7, an observation window 8, a high-pressure air cylinder 9, an intake valve 10, a heating device 11, an exhaust valve 12, an exhaust gas treatment device 13, an injector 14, and an injector end cap 15.

[0056] The inner wall of the constant-volume combustion bomb 1 is cylindrical, and the outer wall is cubic. The observation window 8 is made of quartz glass, which is connected to the constant-volume combustion bomb 1 via the window end cap 6. The observation window 8 is the same size as the injector end cap 15 and the injection valve end cap 3. By replacing the observation window 8 with the injector end cap 15 and the injection valve end cap 3, the purpose of arranging the injector 14, the injection valve 4, or the observation window 8 at the window position can be achieved. The heating device 11 is located at the bottom inside the constant-volume combustion bomb 1, and the thermocouple 5 is located at the top inside the constant-volume combustion bomb 1. The upper part of the constant-volume combustion bomb 1 is connected in sequence with the exhaust valve 12 and the exhaust gas treatment device 13. The lower part is connected in sequence with the intake valve 10 and the high-pressure air cylinder 9.

[0057] There are a maximum of four observation windows 8, and rubber gaskets 7 are used to ensure the airtightness of the constant-volume incendiary bomb 1. The installation position of the heating device 11 does not affect the observation through the observation windows 8 or the operation of the fuel injector 14 or the injection valve 4.

[0058] This invention provides a method for testing the atomization and combustion of variable-angle jets from multiple fuel injectors in an engine. The specific working steps are described in detail using ammonia-diesel dual-fuel as an example (ammonia is the main fuel and diesel is the ignition fuel), which does not constitute an improper limitation of this invention.

[0059] Before starting the test device, select the ammonia injection valve 4 and diesel injector 14 that are compatible with the required test fuel, and customize the ammonia injection valve end cap 3 and diesel injector end cap 15 that are compatible with the ammonia injection valve 4 and diesel injector 14 respectively.

[0060] Arrange the positions of the ammonia injection valve end cap 3 and the diesel injector end cap 15 according to the required ammonia and diesel spray jet angles to be tested.

[0061] The timing, duration, and pressure of the fuel injection are determined and controlled via an external synchronization controller;

[0062] Determine the required test conditions, and determine the cylinder pressure and temperature under those conditions;

[0063] To test fuel jet spray characteristics:

[0064] The temperature inside the constant volume combustion bomb 1 is adjusted to T1 (T1 = the measured cylinder temperature at the operating point minus 20K) by the heating device 11, and the temperature inside the constant volume combustion bomb 1 is monitored by the thermocouple 5.

[0065] Furthermore, after the temperature inside the constant volume combustion bomb 1 stabilizes, the pressure inside the constant volume combustion bomb 1 is adjusted to P1 (i.e., the pressure at the measured operating point) through the high-pressure air bottle 9.

[0066] According to the ideal gas law PV=nRT, the temperature will also increase as the pressure increases. Therefore, when adjusting the pressure, the temperature inside the constant volume combustion bomb 1 gradually approaches the measured operating point temperature.

[0067] After the pressure is adjusted, the heating device 11 is used to adjust the temperature inside the constant volume combustion bomb 1 to T2 (i.e. the measured operating point temperature), and the temperature inside the constant volume combustion bomb 1 is monitored by the thermocouple 5.

[0068] Furthermore, the ammonia injection valve 14 is activated, and a high-pressure ammonia jet enters the test device;

[0069] Furthermore, diesel injector 4 is activated, and a high-pressure diesel jet enters the test device;

[0070] Any viewing window 6 can be selected for light intake, while the other viewing window 6 opposite it uses optical testing equipment to record its spray characteristics;

[0071] To test the combustion characteristics of a fuel jet:

[0072] Determine the temperature and pressure required for diesel fuel to be compressed and ignited;

[0073] The temperature inside the constant volume combustion bomb 1 is adjusted to the measured operating point cylinder temperature by the heating device 11, and the temperature inside the constant volume combustion bomb 1 is monitored by the thermocouple 5.

[0074] Furthermore, after the temperature inside the cylinder stabilizes, the pressure inside the constant-volume combustion bomb 1 is adjusted to the pressure at the measured operating point using the high-pressure air bottle 9.

[0075] According to the ideal gas law PV=nRT, the temperature will also increase as the pressure increases. Therefore, when adjusting the pressure, the temperature inside the constant volume combustion bomb 1 gradually approaches the measured operating point temperature.

[0076] After the pressure is adjusted, the heating device 11 is used to adjust the temperature inside the constant volume combustion bomb 1 to T2 (i.e. the measured operating point temperature), and the temperature inside the constant volume combustion bomb 1 is monitored by the thermocouple 5.

[0077] Furthermore, the ammonia injection valve 14 is activated, and a high-pressure ammonia jet enters the test device;

[0078] Furthermore, diesel injector 4 is activated, and a high-pressure diesel jet enters the test device;

[0079] Furthermore, by increasing the internal pressure of the constant-volume combustion bomb 1, it is made to reach the diesel compression ignition set value and burn;

[0080] Optical testing equipment can be placed at any one or several windows to record its combustion characteristics;

[0081] After combustion is complete, intake valve 10 and exhaust valve 12 open simultaneously. Air enters the lower part of constant volume combustion bomb 1 from high pressure air cylinder 9 through pipeline and is discharged from the top of constant volume combustion bomb 1, thereby completing in-cylinder scavenging. The exhaust gas and air mixture enters exhaust gas treatment device 13 through pipeline, and is discharged after purification.

[0082] After exhausting the gas, the above steps can be repeated to perform multiple repeatable experiments.

[0083] In addition, the spray coupling and combustion characteristics of dual fuels under different operating conditions can be achieved by synchronously controlling the injection quantity, injection time, ambient density and air temperature of ammonia and diesel.

[0084] In addition, the coupling atomization and combustion characteristics of different fuels can be measured by arranging injectors at multiple windows. For example, three injectors can be arranged, one injector injecting the main combustion fuel and two injectors injecting the ignition fuel, or two injectors injecting the main combustion fuel and one injector injecting the ignition fuel.

[0085] The above constitutes a technical solution for a test device and method for variable angle jet atomization and combustion of multi-injector fuel injectors in an engine.

[0086] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A test device for simulating multi-injector coupled atomization and combustion in an engine, characterized in that: It includes a constant volume incendiary bomb (1), an injection valve end cap (3), an injection valve (4), a thermocouple (5), a viewing window end cap (6), an observation window (8), a high-pressure air cylinder (9), an intake valve (10), a heating device (11), an exhaust valve (12), an exhaust gas treatment device (13), an injector (14), and an injector end cap (15). The inner wall of the constant volume incendiary bomb (1) is cylindrical and the outer wall is cubic. The observation window (8) is made of quartz glass and is connected to the constant volume incendiary bomb (1) by fixing bolts (2) through the end cap (6). The observation window (8) is the same size as the injector end cap (15) and the injection valve end cap (3). By replacing the observation window (8) with the injector end cap (15) and the injection valve end cap (3), the purpose of arranging the injector (14) or the injection valve (4) or the observation window (8) at the window position can be achieved. The heating device (11) is located at the bottom inside the constant volume incendiary bomb (1), and the thermocouple (5) is located at the top inside the constant volume incendiary bomb (1); The upper part of the constant volume incendiary bomb (1) is connected to an exhaust valve (12) and a tail gas treatment device (13); the lower part is connected to an air inlet valve (10) and a high-pressure air cylinder (9). The testing method steps of the testing device are as follows: Step 1: Before starting the test device; Select the appropriate injection valve and injector based on the required test fuel, and customize the injection valve end cap and injector end cap to match the injection valve and injector respectively. Step 2: Start the test; Arrange the positions of the injection valve end cap and injector end cap according to the spray angle of the test fuel; determine the fuel injection timing, duration and injection pressure, and regulate them through an external synchronization controller; determine the cylinder pressure and temperature; Step 3: Test the fuel jet spray characteristics or jet combustion characteristics; (1) If testing fuel jet spray characteristics: The temperature inside the constant-volume combustion bomb is adjusted to T1 by the heating device. T1 = the measured cylinder temperature at the operating point minus 20K. The temperature inside the constant-volume combustion bomb is monitored by thermocouples. After the temperature inside the constant volume combustion bomb stabilizes, the pressure inside the constant volume combustion bomb is adjusted to P1, which is the pressure at the measured operating point, through the high-pressure air cylinder. According to the ideal gas law PV=nRT, the temperature will also increase as the pressure increases. Therefore, when adjusting the pressure, the temperature inside the constant volume combustion bomb gradually approaches the measured operating point temperature. After the pressure is adjusted, the heating device is used to adjust the temperature inside the constant volume combustion bomb to T2, which is the measured operating point temperature, and the temperature inside the constant volume combustion bomb is monitored by thermocouples. The injection valve is activated, and a high-pressure fuel jet enters the test device; The fuel injector starts working, and a high-pressure fuel jet enters the test device; Choose any observation window for light intake, and use an optical testing device to record its spray characteristics in the opposite window; (2) To test the combustion characteristics of fuel jet: Determine the temperature and pressure required for diesel fuel to be compressed and ignited; The temperature inside the constant-volume combustion bomb is adjusted to the measured operating point cylinder temperature by the heating device, and the temperature inside the constant-volume combustion bomb is monitored by thermocouples. After the temperature inside the cylinder stabilizes, adjust the pressure inside the constant volume combustion bomb to the pressure at the measured operating point using a high-pressure air bottle. According to the ideal gas law PV=nRT, the temperature will also increase as the pressure increases. Therefore, when adjusting the pressure, the temperature inside the constant volume combustion bomb gradually approaches the measured operating point temperature. After the pressure is adjusted, the heating device is used to adjust the temperature inside the constant volume combustion bomb to T2, which is the measured operating point temperature, and the temperature inside the constant volume combustion bomb is monitored by thermocouples. The injection valve is activated, and a high-pressure fuel jet enters the test device; The fuel injector starts working, and a high-pressure fuel jet enters the test device; By increasing the pressure inside the constant-volume incendiary bomb, it reaches the set value for igniting the compression ignition of the fuel and then burns it. Optical testing equipment was set up at one or more windows to record its combustion characteristics. Step 4: Combustion ends; The intake valve and exhaust valve open simultaneously. Air enters the lower part of the constant volume combustion bomb from the high-pressure air cylinder through the pipeline and is discharged from the top of the constant volume combustion bomb, thereby completing the in-cylinder scavenging. The exhaust gas and air mixture enter the exhaust gas treatment device through the pipeline and is discharged after purification. Step 5: Exhaust complete; Repeat the above steps to conduct multiple repeatable experiments.

2. The simulated engine multi-injector coupled atomization and combustion test device according to claim 1, characterized in that: The observation window (8) and the constant volume incendiary bomb (1) are connected by a rubber gasket (7) to ensure the airtightness of the constant volume incendiary bomb (1).

3. The simulated engine multi-injector coupled atomization and combustion test device according to claim 1, characterized in that: The observation window (8) has a maximum of 4 windows.

4. The simulated engine multi-injector coupled atomization and combustion test device according to claim 1, characterized in that: The installation position of the heating device (11) does not affect the observation through the viewing window (8) or the operation of the fuel injector (14) or the injection valve (4).

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