阅读说明：本技术 一种柴油机润滑系统测试装置及测试方法 (Diesel engine lubricating system testing device and testing method ) 是由 商潭苏 王蕊 李波 鲍建军 李震勇 朱振华 贾德鸣 韦明慧 张微 胡云龙 徐顺利 于 2020-07-14 设计创作，主要内容包括：本发明涉及一种柴油机润滑系统测试装置及测试方法,测试装置包括测试用柴油机和试验台架,测试用柴油机机体的多段待测油道上分别开设有安装孔,用以测量润滑机油温度和压力的温度压力传感器通过安装孔和测试用柴油机机体连通,温度压力传感器和安装孔为一一对应连接,用以测量润滑机油流量的流量计的两端和待测油道上的两个安装孔连接,以使待测油道中的润滑机油通过流量计后再流回测试用柴油机机体内；所述温度压力传感器和流量计分别和试验台架信号连接,以传输数据。所述测试方法可以根据所述装置实时、准确地测量出柴油机在不同转速下各位置的润滑机油流量和温度压力分布,以便于对柴油机润滑系统进行定量研究。(The invention relates to a testing device and a testing method for a lubricating system of a diesel engine, wherein the testing device comprises a testing diesel engine and a testing bench, mounting holes are respectively formed in a plurality of sections of oil passages to be tested of a testing diesel engine body, temperature and pressure sensors for measuring the temperature and the pressure of lubricating oil are communicated with the testing diesel engine body through the mounting holes, the temperature and pressure sensors are in one-to-one correspondence connection with the mounting holes, and two ends of a flowmeter for measuring the flow rate of the lubricating oil are connected with two mounting holes in the oil passages to be tested, so that the lubricating oil in the oil passages to be tested flows back into the testing diesel engine body after passing through the; the temperature and pressure sensor and the flowmeter are respectively in signal connection with the test bed to transmit data. The testing method can accurately measure the lubricating engine oil flow and the temperature pressure distribution of the diesel engine at each position under different rotating speeds in real time according to the device, so that quantitative research can be conveniently carried out on the lubricating system of the diesel engine.)

1. The utility model provides a diesel engine lubricating system testing arrangement, includes that test uses diesel engine and test bench, its characterized in that: the temperature and pressure sensor and the flowmeter are arranged outside the diesel engine body for testing, a plurality of mounting holes are formed in the diesel engine body for testing, the engine oil temperature and pressure sensor is communicated with corresponding oil ducts in the diesel engine body for testing through the mounting holes, and the temperature and pressure sensor and the mounting holes are connected in a one-to-one correspondence manner so as to measure the engine oil temperature and the engine oil pressure of the corresponding oil ducts; two ends of the flowmeter are connected with the two mounting holes in a direct or indirect mode, so that engine oil in the oil duct corresponding to the mounting hole serving as the oil inlet can leave the oil duct, enters the flowmeter, flows back to the oil duct of the diesel engine body for testing through the mounting hole serving as the oil outlet; the temperature and pressure sensor and the flowmeter are respectively in signal connection with the test bench so as to transmit measured data to the test bench.

2. The diesel engine lubrication system testing device of claim 1, wherein: the transition joint is installed on the installation hole, and the temperature and pressure sensor and the flowmeter are communicated with the diesel engine body internal oil duct for testing through connection with the transition joint.

3. The diesel engine lubrication system testing device of claim 2, wherein: and a sealant is coated on the transition joint.

4. The diesel engine lubrication system testing device of claim 1, wherein: the flowmeter is an elliptic gear flowmeter.

5. The diesel engine lubricating system testing device according to any one of claims 1 to 4, characterized in that: the diesel engine for testing is a four-cylinder double-shaft balance diesel engine.

6. The diesel engine lubrication system testing device of claim 5, wherein: an oil conveying duct temperature and pressure sensor is connected to an oil conveying duct between an oil pump of the diesel engine body for testing and the oil pump pressure limiting valve, an auxiliary oil duct temperature and pressure sensor is connected to an auxiliary oil duct of the diesel engine body for testing, and a main oil duct temperature and pressure sensor is connected to a main oil duct of the diesel engine body for testing.

7. The diesel engine lubrication system testing device of claim 6, wherein: the oil delivery passages at the third cylinder and the fourth cylinder of the test diesel engine body are communicated through an oil delivery elliptic gear flowmeter; a section of the oil duct at the upstream of the oil cooler of the diesel engine body for testing is disconnected, and the disconnected position is connected with two ends of the front elliptic gear flowmeter of the oil cooler, so that the engine oil flows through the front elliptic gear flowmeter of the oil cooler and then returns to the oil duct of the diesel engine body for testing; the oil outlet end of the distribution pipe is connected with the oil inlet ends of a first-gear main bearing elliptic gear flowmeter, a third-gear main bearing elliptic gear flowmeter, a fourth-gear main bearing elliptic gear flowmeter and a fifth-gear main bearing elliptic gear flowmeter at the same time, the oil outlet end of the first-gear main bearing elliptic gear flowmeter is connected to the first-gear main bearing oil duct of the diesel engine body for testing, the oil outlet end of the third-gear main bearing elliptic gear flowmeter is connected to the third-gear main bearing oil duct of the diesel engine body for testing, the oil outlet end of the fourth-gear main bearing elliptic gear flowmeter is connected to the fourth-gear main bearing oil duct of the diesel engine body for testing, the oil outlet end of the fifth-gear main bearing elliptic gear flowmeter is connected to the fifth-gear main bearing oil duct of the diesel engine body for testing, so as to ensure that the finally corresponding oil flows into each main bearing lubricating main bearing .

8. A test method for a diesel engine lubricating system is characterized in that temperature and pressure sensors and a flowmeter are arranged at different positions of an oil duct of a diesel engine body to be tested, the temperature, the pressure and the flow of engine oil at corresponding positions at different rotating speeds are obtained through direct measurement or calculation, and signal connection is established between the temperature and pressure sensors and a test bench as well as between the flowmeter and the test bench so as to transmit test data; the specific settings are as follows: (1) arranging an oil conveying channel temperature and pressure sensor on an oil conveying channel at the downstream of the oil pump of the diesel engine to measure the temperature and pressure of the engine oil pumped by the oil pump, and calculating the flow of the engine oil pumped by the oil pump according to the temperature and pressure; (2) the oil duct between two adjacent oil cylinders at the downstream of the diesel engine oil pump pressure limiting valve is disconnected, and an oil transportation oval gear flowmeter is connected between two breakpoints to measure the flow of the engine oil flowing through the engine oil pressure limiting valve; (3) the method comprises the following steps that an auxiliary oil duct temperature and pressure sensor is arranged on an auxiliary oil duct of the diesel engine to measure the oil temperature and pressure of the auxiliary oil duct, and the oil flow of a piston cooling nozzle under the measured pressure is calculated by combining with the characteristic data of the piston cooling nozzle; (4) disconnecting an oil duct in front of an engine oil cooler on the diesel engine, and connecting a front elliptic gear flowmeter of the engine cooler between two breakpoints to measure the flow of engine oil flowing through the engine oil cooler; (5) a main oil gallery temperature and pressure sensor is arranged in a main oil gallery of the diesel engine to measure the engine oil temperature and pressure of the main oil gallery; (6) and respectively arranging a flowmeter between a distribution pipe on the main oil duct of the diesel engine and each grade of main bearing connected with the distribution pipe so as to obtain the flow of the engine oil flowing into each grade of main bearing.

9. The method of claim 8, wherein each of the temperature and pressure sensors and each of the flow meters are connected to a mounting hole formed in the test diesel engine by a transition joint.

10. The method for testing the lubrication system of the diesel engine according to claim 8, wherein the diesel engine for testing is a four-cylinder biaxial balanced diesel engine, the oil outlet end of the distribution pipe is simultaneously connected with the oil inlet ends of a first-gear main bearing elliptic gear flowmeter, a third-gear main bearing elliptic gear flowmeter, a fourth-gear main bearing elliptic gear flowmeter and a fifth-gear main bearing elliptic gear flowmeter, the oil outlet end of the first-gear main bearing elliptic gear flowmeter is connected with the first-gear main bearing oil duct of the diesel engine for testing, the oil outlet end of the third-gear main bearing elliptic gear flowmeter is connected with the third-gear main bearing oil duct of the diesel engine for testing, the oil outlet end of the fourth-gear main bearing elliptic gear flowmeter is connected with the fourth-gear main bearing oil duct of the diesel engine for testing, and the oil outlet end of the fifth-gear main bearing elliptic gear flowmeter, so as to ensure that the main bearing is lubricated by each main bearing oil passage of the diesel engine for the inflow test corresponding to the engine oil finally.

Technical Field

The invention belongs to the technology of diesel engine detection, and particularly relates to a device and a method for testing a lubricating system of a diesel engine.

Background

The lubricating system is one of the indispensable systems of the diesel engine, and directly influences the normal operation and the service life of the diesel engine. When the diesel engine works, the diesel engine needs continuous and sufficient engine oil lubrication to reduce the friction resistance among transmission parts and the part abrasion, reduce the power consumption and take away heat, impurities and the like generated by friction. Modern diesel engine lubricating systems are basically the same and are all internal oil ways, and the lubricating system can only be connected with a sensor to measure the pressure of the engine oil at each position in the test, but cannot determine the flow of the engine oil at each position in the diesel engine lubricating system, and lacks quantitative data of the flow of the engine oil at each position. When the engine oil amount is too much, the power consumption of the engine oil pump is increased, and the effective power output by the diesel engine is reduced; when the engine oil amount is too small, the engine oil pressure is low, an oil film is difficult to form on the friction surface of the transmission piece, and the transmission piece of the diesel engine is excessively worn. Therefore, it is urgently needed to design a testing device and a testing method for a diesel engine lubricating system, so as to facilitate quantitative research on the diesel engine lubricating system.

Disclosure of Invention

The invention aims to provide a testing device and a testing method for a lubricating system of a diesel engine, which can accurately measure the engine oil flow and the temperature pressure distribution of the diesel engine at each position under different rotating speeds in real time when the lubricating system of the diesel engine is tested on a test bench.

In order to achieve the purpose, the invention adopts the technical scheme that: a testing device of a diesel engine lubricating system comprises a testing diesel engine, a test bench, a temperature pressure sensor and a flowmeter, wherein the temperature pressure sensor and the flowmeter are arranged outside a testing diesel engine body; two ends of the engine oil flowmeter are connected with the two mounting holes in a direct or indirect mode, so that the engine oil in the oil duct corresponding to the mounting hole serving as the oil inlet can leave the oil duct, enters the flowmeter, flows back to the oil duct of the diesel engine body for testing through the mounting hole serving as the oil outlet; the temperature and pressure sensor and the flowmeter are respectively in signal connection with the test bench so as to transmit measured data to the test bench.

The transition joint is installed on the installation hole, and the temperature and pressure sensor and the flowmeter are communicated with the diesel engine body internal oil duct for testing through connection with the transition joint.

And a sealant is coated on the transition joint.

The flowmeter is an elliptic gear flowmeter.

The diesel engine for testing is a four-cylinder double-shaft balance diesel engine.

An oil conveying duct temperature and pressure sensor is connected to an oil conveying duct between an oil pump of the diesel engine body for testing and the oil pump pressure limiting valve, an auxiliary oil duct temperature and pressure sensor is connected to an auxiliary oil duct of the diesel engine body for testing, and a main oil duct temperature and pressure sensor is connected to a main oil duct of the diesel engine body for testing.

The oil delivery passages at the third cylinder and the fourth cylinder of the test diesel engine body are communicated through an oil delivery elliptic gear flowmeter; a section of the oil duct at the upstream of the oil cooler of the diesel engine body for testing is disconnected, and the disconnected position is connected with two ends of the front elliptic gear flowmeter of the oil cooler, so that the engine oil flows through the front elliptic gear flowmeter of the oil cooler and then returns to the oil duct of the diesel engine body for testing; the oil outlet end of the distribution pipe is connected with the oil inlet ends of a first-gear main bearing elliptic gear flowmeter, a third-gear main bearing elliptic gear flowmeter, a fourth-gear main bearing elliptic gear flowmeter and a fifth-gear main bearing elliptic gear flowmeter at the same time, the oil outlet end of the first-gear main bearing elliptic gear flowmeter is connected to the first-gear main bearing oil duct of the diesel engine body for testing, the oil outlet end of the third-gear main bearing elliptic gear flowmeter is connected to the third-gear main bearing oil duct of the diesel engine body for testing, the oil outlet end of the fourth-gear main bearing elliptic gear flowmeter is connected to the fourth-gear main bearing oil duct of the diesel engine body for testing, the oil outlet end of the fifth-gear main bearing elliptic gear flowmeter is connected to the fifth-gear main bearing oil duct of the diesel engine body for testing, so as to ensure that the finally corresponding oil flows into each main bearing lubricating main bearing .

A test method for a diesel engine lubricating system comprises the steps of arranging temperature and pressure sensors and a flowmeter at different positions of an oil duct of a diesel engine body to be tested, obtaining the temperature, pressure and flow of engine oil at corresponding positions at different rotating speeds through direct measurement or calculation, and establishing signal connection between the temperature and pressure sensors and a test bench as well as between the flowmeter and the test bench to transmit test data; the specific settings are as follows: (1) arranging an oil conveying channel temperature and pressure sensor on an oil conveying channel at the downstream of the oil pump of the diesel engine to measure the temperature and pressure of the engine oil pumped by the oil pump, and calculating the flow of the engine oil pumped by the oil pump according to the temperature and pressure; (2) the oil duct between two adjacent oil cylinders at the downstream of the diesel engine oil pump pressure limiting valve is disconnected, and an oil transportation oval gear flowmeter is connected between two breakpoints to measure the flow of the engine oil flowing through the engine oil pressure limiting valve; (3) the method comprises the following steps that an auxiliary oil duct temperature and pressure sensor is arranged on an auxiliary oil duct of the diesel engine to measure the oil temperature and pressure of the auxiliary oil duct, and the oil flow of a piston cooling nozzle under the measured pressure is calculated by combining with the characteristic data of the piston cooling nozzle; (4) disconnecting an oil duct in front of an engine oil cooler on the diesel engine, and connecting a front elliptic gear flowmeter of the engine cooler between two breakpoints to measure the flow of engine oil flowing through the engine oil cooler; (5) a main oil gallery temperature and pressure sensor is arranged in a main oil gallery of the diesel engine to measure the engine oil temperature and pressure of the main oil gallery; (6) and respectively arranging a flowmeter between a distribution pipe on the main oil duct of the diesel engine and each grade of main bearing connected with the distribution pipe so as to obtain the flow of the engine oil flowing into each grade of main bearing.

And each temperature and pressure sensor and each flowmeter are connected with a mounting hole formed on the diesel engine for testing through a transition joint.

The diesel engine for testing is a four-cylinder double-shaft balance diesel engine, the oil outlet end of the distribution pipe is simultaneously connected with the oil inlet ends of a first-gear main bearing elliptic gear flowmeter, a third-gear main bearing elliptic gear flowmeter, a fourth-gear main bearing elliptic gear flowmeter and a fifth-gear main bearing elliptic gear flowmeter, the oil outlet end of the first-gear main bearing elliptic gear flowmeter is connected to the first-gear main bearing oil duct of the diesel engine for testing, the oil outlet end of the third-gear main bearing elliptic gear flowmeter is connected to the third-gear main bearing oil duct of the diesel engine for testing, the oil outlet end of the fourth-gear main bearing elliptic gear flowmeter is connected to the fourth-gear main bearing oil duct of the diesel engine for testing, the oil outlet end of the fifth-gear main bearing elliptic gear flowmeter, so as to ensure that the main bearing is lubricated by each main bearing oil passage of the diesel engine for the inflow test corresponding to the engine oil finally.

The invention has the beneficial effects that: the invention can carry out quantitative test of the lubricating system of the diesel engine on the test bed, the temperature and pressure distribution of the engine oil in each oil duct of the lubricating system of the diesel engine can be obtained by the temperature and pressure sensor under different rotating speeds, the flow of the engine oil at the corresponding position can be obtained by the flowmeter, and the temperature and pressure sensor and the flowmeter are connected with the test bed through signal transmission, thus converting the qualitative analysis of the lubricating system of the diesel engine into the quantitative analysis with data support and providing test basis for the optimization and improvement of the lubricating system of the diesel engine.

Drawings

FIG. 1 is a schematic structural view of the present invention;

FIG. 2 is a schematic diagram of the pipeline connection of the testing device and the oil circuit of the lubricating system of the diesel engine in the invention, wherein the dotted line represents the disconnection of the original oil channel;

the labels in the figure are: 1. the testing method comprises the following steps of testing a diesel engine body, 2, a transition joint, 3, a temperature pressure sensor, 4, an elliptic gear flowmeter, 5, a test bench, 6, an oil delivery channel temperature pressure sensor, 7, an oil delivery elliptic gear flowmeter, 8, a secondary oil channel temperature pressure sensor, 9, an engine oil cooler front elliptic gear flowmeter, 10, a main oil channel temperature pressure sensor, 11, a distribution pipe, 12, a first-gear main bearing elliptic gear flowmeter, 13, a third-gear main bearing elliptic gear flowmeter, 14, a fourth-gear main bearing elliptic gear flowmeter, 15 and a fifth-gear main bearing elliptic gear flowmeter; 16. the oil pump 17, the oil pump pressure limiting valve 18, the oil filter 19, the first gear main bearing 20, the second gear main bearing 21, the third gear main bearing 22, the fourth gear main bearing 23, the fifth gear main bearing 24, the gear train and the hydraulic pump 25 and the left balance shaft;

i, an oil delivery channel, II, an auxiliary oil channel, III, an engine oil cooler, IV and a main oil channel;

it should be noted that: four arrows on the auxiliary oil passage perpendicular to the auxiliary oil passage represent four piston cooling nozzles, and the arrows on the other oil passages represent the flow direction of engine oil.

Detailed Description

The present invention will be described in further detail with reference to the following drawings and examples, but the invention is not limited thereto.

Referring to the attached drawing 1, the testing device for the lubricating system of the diesel engine comprises a diesel engine body 1 for testing and a test bench 5, wherein the test bench adopts an eddy current dynamometer with the type GWD250, mounting holes are respectively formed in different positions of an oil way on the diesel engine body 1 for testing, a transition joint 2 is fixed on each mounting hole, the transition joint 2 is communicated with the oil way in the diesel engine body 1 for testing, and in order to ensure the sealing property, a sealing glue is smeared between the transition joint 2 and the diesel engine body 1 for testing. The temperature and pressure sensors 3 for measuring the temperature and pressure of the engine oil are installed on the transition joint 2 one-to-one, and the temperature and pressure sensors 3 are in signal connection with the test bed 5, and the measured results are transmitted to the test bed 5. An inlet and an outlet of an elliptic gear flowmeter 4 for measuring the flow of engine oil are connected with two transition joints 2 at positions to be measured, so that the engine oil flows into a diesel engine body 1 for testing after passing through the elliptic gear flowmeter 4, the flow is measured, a sender of the elliptic gear flowmeter 4 is connected with a test bench 5, and the measured flow information is converted into pulse signals and is transmitted to the test bench 5.

Referring to fig. 2, in the present embodiment, the four-cylinder biaxial balanced diesel engine is selected for the test diesel engine, and the temperature and pressure sensor 3 and the oval gear flowmeter 4 are arranged as follows:

1. an oil conveying channel temperature and pressure sensor 6 is arranged on an oil conveying channel at the downstream of an oil pump 16 and at the upstream of an oil pump pressure limiting valve 17 of the diesel engine body 1 for testing, and the flow of the engine oil pumped by the oil pump 16 at the temperature of the engine oil can be obtained according to the temperature and the pressure of the engine oil measured by the oil conveying channel temperature and pressure sensor 6;

2. the original oil conveying passage between the third cylinder and the fourth cylinder of the diesel engine body 1 for testing is disconnected, and the break points are connected with the two ends of the oil conveying oval gear flowmeter 7, so that the engine oil can be ensured to flow back to the oil passage of the diesel engine body after flowing through the oil conveying oval gear flowmeter 7, the engine oil flow under the corresponding diesel engine rotating speed can be measured, and the engine oil flow after flowing through the engine oil pump pressure limiting valve 17 can be obtained;

3. the auxiliary oil duct of the diesel engine body 1 for testing is connected with an auxiliary oil duct temperature and pressure sensor 8, so that the engine oil temperature and pressure of the auxiliary oil duct can be obtained, and the engine oil flow of four piston cooling nozzles under the pressure can be calculated according to the characteristic data of the piston cooling nozzles;

4. the oil cooler front elliptic gear flowmeter 9 is connected to an oil path disconnection position on the upstream of an oil cooler of the diesel engine body 1 for testing so as to ensure that engine oil flows back to an oil path of the oil cooler after flowing through the oil cooler front elliptic gear flowmeter 9, and the flow rate of the engine oil flowing through the oil cooler is measured by the oil cooler front elliptic gear flowmeter 9;

5. a main oil duct temperature and pressure sensor 10 is connected to a main oil duct of the diesel engine body 1 for testing, and the main oil duct temperature and pressure sensor 10 is located at the upstream of the distribution pipe 11 and is used for measuring the engine oil temperature and pressure of the main oil duct;

6. the oil inlet end of the distribution pipe 11 is connected with a second-gear main bearing hole of the original main oil duct through a transition joint, the oil outlet end of the distribution pipe 11 is simultaneously connected with a first-gear main bearing elliptic gear flowmeter 12, a third-gear main bearing elliptic gear flowmeter 13, a fourth-gear main bearing elliptic gear flowmeter 14 and a fifth-gear main bearing elliptic gear flowmeter 15, the other end of the first-gear main bearing elliptic gear flowmeter 12 is connected with a transition joint corresponding to a first-gear main bearing oil duct of the diesel engine body 1 for testing, the other end of the third-gear main bearing elliptic gear flowmeter 13 is connected with a transition joint corresponding to a third-gear main bearing oil duct of the diesel engine body 1 for testing, the other end of the fourth-gear main bearing elliptic gear flowmeter 14 is connected with a transition joint corresponding to a fourth-gear main bearing oil duct of the diesel engine body 1 for testing, and the other end of the fifth-gear main bearing elliptic gear flowmeter 15 So as to ensure that the engine oil finally flows into each main bearing oil passage in the diesel engine body 1 to lubricate the corresponding main bearings ( reference numerals 19, 21, 22 and 23).

It should be noted that: (1) a branch oil path is arranged on the main oil passage and connected with a second-gear main bearing 20, and the connection position of the branch oil path is positioned at the upstream of the distribution pipe 11 and the installation position of the main oil passage temperature and pressure sensor 10.

(2) The calculation of the oil flow of the oil pump can be carried out by referring to the following method: firstly, the rotating speed characteristic test of the oil pump under different temperatures is carried out on the oil pump, the oil supply quantity of the oil pump under different temperatures, rotating speeds and pumping pressures is measured, then the oil temperature of the oil conveying channel and the oil conveying channel pressure (namely the pumping pressure of the oil pump) can be measured according to the device of the invention, the rotating speed of the oil pump is calculated according to the rotating speed of the diesel engine under the condition through the speed ratio of a transmission gear, and finally the oil supply quantity of the oil pump under the condition is found through a difference value calculation mode by combining the data obtained in the rotating speed characteristic test of the oil pump, namely the oil flow quantity pumped out.

(3) The method for calculating the oil flow of the four piston cooling nozzles under the pressure according to the characteristic data of the piston cooling nozzles comprises the following steps: the device can measure the oil temperature and the oil pressure of the auxiliary oil duct, and then find the oil injection quantity of the piston cooling nozzle under the condition in a difference value calculation mode.

(4) The engine oil flow of the second-gear main bearing can be calculated according to the following method: the device can directly measure the oil flow of the first, third, fourth and fifth main bearings and the oil flow before the oil cooler, the oil is not lost after passing through the oil cooler and is directly distributed to the first, second, third, fourth and fifth main bearings to lubricate the main bearings, therefore, the oil flow flowing into the second main bearing = the oil flow before the oil cooler-the oil flow of the first main bearing-the oil flow of the third main bearing-the oil flow of the fourth main bearing-the oil flow of the fifth main bearing.

(5) The broken line in fig. 2 indicates the break of the originally designed oil passage, and the oil passage may not be machined at the break position on the diesel engine for testing.

The method for testing the lubricating system of the diesel engine by using the device comprises the following steps:

step one, installing a temperature pressure sensor 3 and an elliptic gear flowmeter 4 according to the arrangement mode of the device, and establishing signal connection between the temperature pressure sensor 3 and the elliptic gear flowmeter 4 and a test bed 5;

changing the rotating speed of the diesel engine when the diesel engine is tested to run, and recording data of an oil conveying duct temperature and pressure sensor 6, an oil conveying elliptic gear flowmeter 7, an auxiliary oil duct temperature and pressure sensor 8, an engine oil cooler front elliptic gear flowmeter 9, a main oil duct temperature and pressure sensor 10, a distribution pipe 11, a first-gear main bearing elliptic gear flowmeter 12, a third-gear main bearing elliptic gear flowmeter 13, a fourth-gear main bearing elliptic gear flowmeter 14 and a fifth-gear main bearing elliptic gear flowmeter 15 through a test bench 5 at different rotating speeds;

step three, under a certain rotating speed of the diesel engine for testing, according to the temperature and the pressure of the engine oil measured by the oil transportation channel temperature pressure sensor 6, the flow of the engine oil pumped out by the engine oil pump under the temperature of the engine oil can be obtained; according to the engine oil flow measured by the oil delivery elliptic gear flowmeter 7, the engine oil flow after flowing through the engine oil pump pressure limiting valve can be obtained; according to the temperature and the pressure of the engine oil measured by the temperature and pressure sensor 8 of the auxiliary oil duct, the temperature and the pressure of the engine oil of the auxiliary oil duct can be obtained, and then the flow of the engine oil of the four piston cooling nozzles under the pressure can be calculated by combining with the characteristic data of the piston cooling nozzles; according to the engine oil flow measured by the front oval gear flowmeter 9 of the engine oil cooler, the engine oil flow passing through the engine oil cooler can be obtained; according to the engine oil temperature and pressure measured by the main oil gallery temperature and pressure sensor 10, the engine oil temperature and pressure of the main oil gallery can be obtained; according to the engine oil flow measured by the first gear main bearing elliptic gear flowmeter 12, the engine oil flow flowing into the first gear main bearing 19 can be obtained; according to the engine oil flow measured by the third-gear main bearing elliptic gear flowmeter 13, the engine oil flow flowing into the third-gear main bearing 21 can be obtained; according to the engine oil flow measured by the elliptical gear flowmeter 14 of the fourth gear main bearing, the engine oil flow 22 flowing into the fourth gear main bearing can be obtained; according to the engine oil flow measured by the elliptic gear flowmeter for the fifth gear main bearing 15, the engine oil flow flowing into the fifth gear main bearing 23 can be obtained;

step four: and calculating the oil flow rate flowing into the main bearing 20 of the second gear according to the measurement result of the third step.

The above embodiments are only intended to illustrate the technical solution of the present invention and not to limit the same, and it should be understood by those of ordinary skill in the art that the specific embodiments of the present invention can be modified or substituted with equivalents with reference to the above embodiments, and any modifications or equivalents without departing from the spirit and scope of the present invention are within the scope of the claims to be appended.