Variable-angle jet flow atomization and combustion testing device and method for multiple fuel injectors of engine

Abstract

The invention discloses a variable-angle jet atomization and combustion testing device and method for multiple oil injectors of an engine, the inner wall of a constant-volume combustion bomb is cylindrical, the inner wall is matched with the geometrical shape in an engine cylinder, and the spraying and combustion characteristics of fuel jet of the engine can be better simulated; a test result can be better applied to internal combustion engines carried by vehicles / ships and the like; the spraying and combustion characteristics of the multi-element green fuel can be tested and analyzed by replacing the oil sprayer / injection valve and the oil sprayer end cover matched with the oil sprayer / injection valve; by replacing the fuel injectors at different windows, a plurality of same ignition fuels can ignite one main combustion fuel, one ignition fuel can ignite a plurality of same main combustion fuels, and a plurality of same ignition fuels can ignite a plurality of same main combustion fuels; and an observation window or an oil sprayer end cover is used at the window to realize different functions of window observation or oil spraying, so that spray jet flow and combustion characteristics at 90 degrees and 180 degrees can be tested.

Description

Technical Field

[0001] The invention belongs to the field of power and energy engineering, and in particular relates to a variable-angle jet atomization and combustion testing device and method for engine multi-injectors. Background Art

[0002] As a common power device, the internal combustion engine has the advantages of good fuel economy, high thermal efficiency, large torque, good durability and economy. It has been widely used in aerospace, transportation and other fields. Since the birth of the internal combustion engine, it has been continuously updated and optimized in pursuit of excellent power and economy.

[0003] With the iterative development of internal combustion engine technology and the increasingly stringent global emission standards for internal combustion engines, internal combustion engines are constantly developing in the direction of high efficiency and cleanliness. There are many technologies to reduce the energy consumption and emissions of internal combustion engines. The results that can be achieved by adjusting parameters in the structure and working process of internal combustion engines to reduce the above performance indicators are limited. Therefore, in the final analysis, it is necessary to find methods from the fuel used by the internal combustion engine to achieve the goal of energy conservation and emission reduction. Increasingly stringent carbon dioxide emission regulations have prompted internal combustion engines to use more green low / zero carbon fuels in the future. Therefore, it is urgent to test the spray and combustion characteristics of different green low / zero carbon fuels in internal combustion engines. Low / zero carbon fuels include biomethanol, biodiesel, hydrogen, and ammonia. For different fuels, due to their different physical and chemical properties, the corresponding injector specifications in the internal combustion engine are also different. Therefore, in order to facilitate the measurement of different fuel spray and combustion characteristics in the same test device, the test device is required to be able to adapt to injectors of different specifications. However, compared with traditional fuels, there are problems in use such as difficulty in ignition, low calorific value, and inability to be applied to existing models. Therefore, research on the spray and combustion characteristics of green carbon fuels in internal combustion engine cylinders is extremely important.

[0004] However, since green low / zero fuels such as ammonia fuel are not easy to burn and have a low laminar flame speed, their economic performance is worse than that of pure diesel engines under the same conditions. Therefore, other green low / zero carbon fuels need to be added to activate their chemical properties and assist combustion. Therefore, dual-fuel spray and combustion tests are particularly important for energy conservation and emission reduction of internal combustion engines. However, there are very few devices that can test the low / zero carbon dual-fuel spray and combustion characteristics. If the requirement of variable relative positions of different fuel spray injections is met, the existing test equipment is almost blank. Therefore, there is an urgent need for an engine multi-injector variable angle jet atomization and combustion test device and method. Summary of the invention

[0005] The object of the present invention is to provide a variable-angle jet atomization and combustion testing device and method for multiple fuel injectors of an engine.

[0006] The purpose of the present invention is achieved through the following technical solutions:

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

[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 through the window end cover using fixing bolts;

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

[0010] The heating device is located at the bottom of the constant volume combustion bomb, and the thermocouple is located at the top of the constant volume combustion bomb;

[0011] The upper part of the constant volume combustion bomb is connected with an exhaust valve and an exhaust gas treatment device in sequence; the lower part is connected with an intake valve and a high-pressure air bottle in sequence.

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

[0013] Furthermore, the number of the observation windows is at most 4.

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

[0015] A method for simulating engine multi-injector coupled atomization and combustion test, as follows:

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

[0017] Select the injection valve and fuel injector that match the required test fuel, and customize the injection valve end cover and fuel injector end cover that match the injection valve and fuel injector respectively;

[0018] Step 2: Start testing;

[0019] Arrange the position of the injection valve end cover and the injector end cover according to the spray jet angle of the test fuel; determine the fuel injection time, duration and injection pressure, and control them through an external synchronous controller; determine the pressure and temperature in the cylinder;

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

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

[0022] The temperature in the constant volume combustion bomb is adjusted to T1 by the heating device, where T1 = the cylinder temperature at the measured working condition minus 20K, and the temperature in the constant volume combustion bomb is monitored by a thermocouple;

[0023] After the temperature inside the constant volume combustion bomb is stabilized, the pressure inside the constant volume combustion bomb is adjusted to P1, i.e. the pressure at the measured working condition point, through the high-pressure air bottle;

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

[0025] After the pressure is adjusted, the temperature inside the constant volume combustion bomb is adjusted to T2, i.e. the temperature at the measured working point, using a heating device, and the temperature inside the constant volume combustion bomb is monitored by a thermocouple;

[0026] The injection valve starts to work and a high-pressure fuel jet enters the test device;

[0027] The injector starts to work and the high-pressure fuel jet enters the test device;

[0028] Select any observation window for light entry, and use an optical test device to record the spray characteristics of the other window opposite to it;

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

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

[0031] The temperature inside the constant volume combustion bomb is adjusted to the cylinder temperature at the measured working condition point by the heating device, and the temperature inside the constant volume combustion bomb is monitored by the thermocouple;

[0032] After the temperature in the cylinder is stable, the pressure in the constant volume combustion bomb is adjusted to the pressure of the measured working condition point through the high-pressure air bottle;

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

[0034] After the pressure is adjusted, the temperature inside the constant volume combustion bomb is adjusted to T2, i.e. the temperature at the measured working point, using a heating device, and the temperature inside the constant volume combustion bomb is monitored by a thermocouple;

[0035] The injection valve starts to work and a high-pressure fuel jet enters the test device;

[0036] The injector starts to work and the high-pressure fuel jet enters the test device;

[0037] By increasing the pressure inside the constant volume combustion bomb, it reaches the set value for the ignition fuel compression ignition and burns;

[0038] Arrange optical testing equipment at any one or several windows to record the combustion characteristics;

[0039] Step 4: Burning ends;

[0040] The intake valve and the exhaust valve are opened at the same time, and the air enters the lower part of the constant volume combustion bomb from the high-pressure air bottle through the pipeline and is discharged from the top of the constant volume combustion bomb, thereby completing the scavenging in the cylinder. The exhaust gas and air mixture enters the exhaust gas treatment device through the pipeline and is discharged after purification;

[0041] Step 5: Exhaust is completed;

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

[0043] The beneficial effects of the present invention are:

[0044] The present invention uses a constant volume combustion bomb with a cylindrical inner wall to ensure matching with the geometric shape of the engine cylinder, which can better simulate the spray and combustion characteristics of the engine fuel jet, so that the test results can be better applied to the internal combustion engines of vehicles / ships;

[0045] The present invention can realize the test and analysis of the spray and combustion characteristics of multi-element green fuel by replacing the injector / injection valve and its matching injector end cover;

[0046] The present invention can realize the testing and analysis of 90° and 180° spray jet and combustion characteristics by replacing the injector end cover and the observation window in the window;

[0047] The present invention can realize that multiple identical pilot fuels can ignite one main fuel, one pilot fuel can ignite multiple identical main fuels, and multiple identical pilot fuels can ignite multiple identical main fuels by replacing the fuel injectors at different windows.

[0048] In summary, the present invention can achieve the purpose of replacing the injector used for different fuels by replacing the injector end cover, using an observation window or injector end cover at the window to achieve different functions of observation or injection of the window, and then testing the spray jet and combustion characteristics at 90° and 180°. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 It is a structural schematic diagram of an engine multi-injector variable angle jet atomization and combustion test device according to an embodiment of the present invention;

[0050] Figure 2 A schematic diagram of a replaceable injector end cover structure of an engine multi-injector variable-angle jet atomization and combustion test device according to an embodiment of the present invention;

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

[0052] Description of reference numerals:

[0053] 1-constant volume combustion bomb; 2-fixing bolt; 3-ammonia injection valve end cover; 4-ammonia injection valve; 5-thermocouple; 6-window end cover; 7-rubber gasket; 8-observation window; 9-high pressure air bottle; 10-intake valve; 11-heating device; 12-exhaust valve; 13-exhaust treatment device; 14-diesel injector; 15-diesel injector end cover. DETAILED DESCRIPTION

[0054] The present invention is further described below in conjunction with the accompanying drawings.

[0055] according to Figure 1-3 The present invention discloses an engine multi-injector variable-angle jet atomization and combustion testing device, comprising a constant-volume combustion bomb 1, a fixing bolt 2, an injection valve end cover 3, an injection valve 4, a thermocouple 5, a window end cover 6, a rubber gasket 7, an observation window 8, a high-pressure air bottle 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 cover 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, and the quartz glass is connected to the constant volume combustion bomb 1 through the window end cover 6; the observation window 8 is the same size as the injector end cover 15 and the injection valve end cover 3, and the purpose of arranging the injector 14 or the injection valve 4 or the observation window 8 at the window position is achieved by replacing the observation window 8 with the injector end cover 15 and the injection valve end cover 3; the heating device 11 is located at the bottom of the constant volume combustion bomb 1, and the thermocouple 5 is located at the top of the constant volume combustion bomb 1; the upper part of the constant volume combustion bomb 1 is connected with the exhaust valve 12 and the exhaust gas treatment device 13 in sequence; the lower part is connected with the intake valve 10 and the high-pressure air bottle 9 in sequence.

[0057] There are at most four observation windows 8, and the rubber gasket 7 is used between the observation windows 8 and the constant volume incendiary bomb 1 to ensure the airtightness of the constant volume incendiary bomb 1. The installation position of the heating device 11 does not affect the observation of the observation window 8 and the operation of the injector 14 or the injection valve 4.

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

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

[0060] Arrange the positions of the ammonia injection valve end cover 3 and the diesel injector end cover 15 according to the required test ammonia and diesel spray jet angles;

[0061] Determine the fuel injection timing, duration and injection pressure, and control them through an external synchronous controller;

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

[0063] To test fuel jet spray characteristics:

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

[0065] Further, after the temperature in the constant volume combustion bomb 1 is stabilized, the pressure in the constant volume combustion bomb 1 is adjusted to P1 (i.e., the measured working point pressure) through the high pressure air bottle 9;

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

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

[0068] Further, the ammonia injection valve 14 is started to work, and the high-pressure ammonia jet enters the test device;

[0069] Further, the diesel injector 4 starts to work, and the high-pressure diesel jet enters the test device;

[0070] Any observation window 6 can be selected for light admission, and the other window 6 opposite to it can be used to record its spray characteristics using an optical test device;

[0071] To test fuel jet combustion characteristics:

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

[0073] The temperature in the constant volume combustion bomb 1 is adjusted to the cylinder temperature at the measured working condition point by the heating device 11, and the temperature in the constant volume combustion bomb 1 is monitored by the thermocouple 5;

[0074] Furthermore, after the temperature in the cylinder is stabilized, the pressure in the constant volume combustion bomb 1 is adjusted to the pressure of the measured working condition point through the high pressure air bottle 9;

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

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

[0077] Further, the ammonia injection valve 14 is started to work, and the high-pressure ammonia jet enters the test device;

[0078] Further, the diesel injector 4 starts to work, and the high-pressure diesel jet enters the test device;

[0079] Furthermore, by increasing the pressure inside the constant volume combustion bomb 1, it reaches the diesel compression ignition setting value and burns;

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

[0081] After the combustion is finished, the intake valve 10 and the exhaust valve 12 are opened at the same time, and the air enters the lower part of the constant volume combustion bomb 1 from the high pressure air bottle 9 through the pipeline, and is discharged from the top of the constant volume combustion bomb 1, thereby completing the scavenging in the cylinder, and the exhaust gas and air mixture enters the exhaust gas treatment device 13 through the pipeline, and is discharged after purification;

[0082] After exhausting, the above steps can be repeated for multiple repetitive experiments;

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

[0084] In addition, injectors may be arranged at multiple windows to measure the coupled atomization and combustion characteristics of different fuels. For example, three injectors may be arranged, one of which injects the main fuel and two of which inject the pilot fuel, or two of which inject the main fuel and one of which injects the pilot fuel.

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

[0086] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A test device for simulating engine multi-injector coupling atomization and combustion, characterized in that: It comprises a constant volume combustion bomb (1), an injection valve end cover (3), an injection valve (4), a thermocouple (5), a window end cover (6), an observation window (8), a high pressure air bottle (9), an air intake valve (10), a heating device (11), an exhaust valve (12), an exhaust gas treatment device (13), a fuel injector (14) and a fuel injector end cover (15); 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, and the quartz glass is connected to the constant volume combustion bomb (1) through the window end cover (6) using a fixing bolt (2); The observation window (8) has the same size as the fuel injector end cover (15) and the injection valve end cover (3). By replacing the observation window (8) with the fuel injector end cover (15) and the injection valve end cover (3), the purpose of arranging the fuel injector (14) or the injection valve (4) or the observation window (8) at the window position is achieved; The heating device (11) is located at the bottom of the constant volume combustion bomb (1), and the thermocouple (5) is located at the top of the constant volume combustion bomb (1); The upper part of the constant volume combustion bomb (1) is connected in sequence to an exhaust valve (12) and an exhaust gas treatment device (13); the lower part is connected in sequence to an intake valve (10) and a high-pressure air bottle (9).

2. The device for testing the coupled atomization and combustion of multiple injectors of a simulated engine according to claim 1, characterized in that: A rubber gasket (7) is used between the observation window (8) and the constant volume incendiary bomb (1) to ensure the air tightness of the constant volume incendiary bomb (1).

3. The device for testing the coupled atomization and combustion of multiple injectors of a simulated engine according to claim 1, characterized in that: The number of the observation windows (8) is at most 4.

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

5. A method for simulating engine multi-injector coupled atomization and combustion testing according to any one of claims 1 to 4, characterized in that: Step 1: Before starting the test device; Select the injection valve and fuel injector that match the required test fuel, and customize the injection valve end cover and fuel injector end cover that match the injection valve and fuel injector respectively; Step 2: Start testing; Arrange the position of the injection valve end cover and the injector end cover according to the spray jet angle of the test fuel; determine the fuel injection time, duration and injection pressure, and control them through an external synchronous controller; determine the pressure and temperature in the cylinder; Step 3: Testing the fuel jet spray characteristics or jet combustion characteristics; (1) If testing fuel jet spray characteristics: The temperature in the constant volume combustion bomb is adjusted to T1 by the heating device, where T1 = the cylinder temperature at the measured working condition minus 20K, and the temperature in the constant volume combustion bomb is monitored by a thermocouple; After the temperature inside the constant volume combustion bomb is stabilized, the pressure inside the constant volume combustion bomb is adjusted to P1, i.e. the pressure at the measured working condition point, through the high-pressure air bottle; According to the ideal gas state equation PV=nRT, as the pressure increases, the temperature will also increase. Therefore, when the pressure is adjusted, the temperature inside the constant volume combustion bomb gradually approaches the measured operating point temperature. After the pressure is adjusted, the temperature inside the constant volume combustion bomb is adjusted to T2, i.e. the temperature at the measured working point, using a heating device, and the temperature inside the constant volume combustion bomb is monitored by a thermocouple; The injection valve starts to work and a high-pressure fuel jet enters the test device; The injector starts working and the high-pressure fuel jet enters the test device; Select any observation window for light entry, and use an optical test device to record the spray characteristics of the other window opposite to it; (2) To test the fuel jet combustion characteristics: Determine the temperature and pressure required for diesel to be compression ignited; The temperature inside the constant volume combustion bomb is adjusted to the cylinder temperature at the measured working condition point by the heating device, and the temperature inside the constant volume combustion bomb is monitored by the thermocouple; After the temperature in the cylinder is stable, the pressure in the constant volume combustion bomb is adjusted to the pressure of the measured working condition point through the high-pressure air bottle; According to the ideal gas state equation PV=nRT, as the pressure increases, the temperature will also increase. Therefore, when the pressure is adjusted, the temperature inside the constant volume combustion bomb gradually approaches the measured operating point temperature. After the pressure is adjusted, the temperature inside the constant volume combustion bomb is adjusted to T2, i.e. the temperature at the measured working point, using a heating device, and the temperature inside the constant volume combustion bomb is monitored by a thermocouple; The injection valve starts to work and a high-pressure fuel jet enters the test device; The injector starts working and the high-pressure fuel jet enters the test device; By increasing the pressure inside the constant volume combustion bomb, it reaches the set value for the ignition fuel compression ignition and burns; Arrange optical testing equipment at any one or several windows to record the combustion characteristics; Step 4: Burning ends; The intake valve and the exhaust valve are opened at the same time, and the air enters the lower part of the constant volume combustion bomb from the high-pressure air bottle through the pipeline and is discharged from the top of the constant volume combustion bomb, thereby completing the scavenging in the cylinder. The exhaust gas and air mixture enters the exhaust gas treatment device through the pipeline and is discharged after purification; Step 5: Exhaust is completed; Repeat the above steps to conduct multiple repetitive experiments.

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