CN115962948A

CN115962948A - Combustion simulation device for heat load experiment of vehicle engine piston

Info

Publication number: CN115962948A
Application number: CN202211558613.8A
Authority: CN
Inventors: 王贵新; 周慧宁; 曹艺隆; 刘帅凝; 俞谦
Original assignee: Harbin Engineering University
Current assignee: Harbin Engineering University
Priority date: 2022-12-06
Filing date: 2022-12-06
Publication date: 2023-04-14

Abstract

The invention aims to provide a combustion simulation device for a heat load experiment of a vehicle engine piston, which comprises a rack, an exhaust pipe, a movable exhaust pipe, a combustion hood bottom plate, a combustion cup and a linear motion mechanism, wherein an upper plate surface is arranged above the rack, a lower plate surface is arranged below the rack, the combustion hood bottom plate is positioned above the lower plate surface, the linear motion mechanism is arranged on one opposite side of the rack, the linear motion mechanism is connected with the combustion hood bottom plate, the combustion hood is positioned on the combustion hood bottom plate, the bottom of the movable exhaust pipe is connected with the combustion hood, the top of the movable exhaust pipe is positioned in the exhaust pipe, the top of the exhaust pipe penetrates through the upper plate surface of the rack and is positioned outside the rack, the combustion cup is positioned below the combustion hood, and a nozzle is arranged on the combustion hood. The invention can be separated from the actual engine to simulate the thermal characteristics of the piston and measure the temperature parameter. The vortex is generated by changing the offset angle of the nozzle, so that the flame diffusion and the temperature uniformity are facilitated.

Description

Combustion simulation device for heat load experiment of vehicle engine piston

Technical Field

The invention relates to a combustion device, in particular to an engine piston simulation combustion device.

Background

To produce a diesel engine with high power density, the design limits of its core components must be known. The upper limit of the output power is directly determined by how much thermal stress the piston can bear without changing the structural material. Therefore, the temperature field of the piston can be accurately measured, and the problem that the magnitude of the thermal stress value of the piston is inevitable in the design process of the engine is explored

For a diesel engine for a vehicle, increasing the power density may deteriorate the working conditions of parts of the diesel engine, wherein a piston of the diesel engine is one of the severest working conditions of all the parts of the diesel engine, the reciprocating characteristic of the piston not only enables the piston to bear the influence of inertia force and bear large mechanical load, but also enables the piston to bear large thermal load due to the periodically changing temperature in a combustion chamber and the large temperature difference between the head part and the skirt part of the piston.

The traditional method for testing the piston temperature field is to assemble a temperature measuring element into an engine for actual test, but because the sensor is easy to fall off when the piston moves at a high speed, the temperature field of the piston is difficult to test under an extremely severe working environment. And then, the temperature field of the piston is obtained through simulation calculation, but because the experimental data is influenced by the flow of the complex gas in the combustion chamber, the simulation result needs to be calibrated through an experiment, and therefore, the experimental study of the temperature field of the piston is indispensable.

Disclosure of Invention

The invention aims to provide a combustion simulation device for a vehicle engine piston thermal load test, which can be used for measuring an engine piston temperature field and performing a piston thermal fatigue test.

The purpose of the invention is realized as follows:

the invention relates to a combustion simulation device for a thermal load experiment of a vehicle engine piston, which is characterized in that: including the rack, the chimney, remove the chimney, the combustion hood bottom plate, the burning cup, linear motion mechanism, the top of rack sets up the face, the below of rack sets up down the face, the combustion hood bottom plate is located face top down, a offside installation linear motion mechanism of rack, linear motion mechanism connects the combustion hood bottom plate, the burning hood is located the combustion hood bottom plate, the combustion hood is connected to the bottom of removing the pipe of discharging fume, the top of removing the pipe of discharging fume is located the pipe of discharging fume, the top of discharging fume passes the last face of rack and is located outside it, the burning cup is located the combustion hood below, install the nozzle on the combustion hood.

The present invention may further comprise:

1. the outer ring of the combustion cover is square, the middle part of the combustion cover is provided with a circular hole, the bottom of the movable smoke exhaust pipe is positioned in the upper part of the circular hole, and the top of the combustion cup is positioned in the lower part of the circular hole.

2. Four faces on the upper part of the outer ring of the combustion cover are inwards inclined to form four inclined planes, and the four inclined planes are all provided with round holes for installing nozzles.

3. The nozzle and the round hole for installing the nozzle are sealed by fireproof and explosion-proof mud.

4. The top of the smoke exhaust tube penetrates through the rack body before penetrating through the upper plate surface.

5. The nozzles are each offset so as to generate a vortex.

6. The smoke exhaust pipe and the movable smoke exhaust pipe are both made of steel pipes, and the combustion cover and the combustion cup are both made of ceramics.

7. Four heat insulation grooves are arranged on the bottom plate of the combustion cover.

The invention has the advantages that:

1. the invention can be separated from the actual engine to simulate the thermal characteristics of the piston and measure the temperature parameter.

2. The vortex is generated by changing the offset angle of the nozzle, so that the flame diffusion and the temperature uniformity are facilitated.

3. The amount of the injected acetylene and the amount of the injected oxygen are adjusted, the flame temperature is changed, the extreme working environment of high-intensity motion of a piston when the engine works under special conditions can be simulated, and a more accurate experimental data calibration simulation data result is obtained.

Drawings

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

FIG. 2 is a schematic view of a combustion chamber.

Detailed Description

The invention will now be described in more detail by way of example with reference to the accompanying drawings in which:

referring to fig. 1-2, the invention relates to a combustion simulation device for a heat load experiment of a vehicle engine piston, which mainly comprises a rack 1, a rack body 2, a smoke exhaust pipe 3, a movable smoke exhaust pipe 4, a nozzle 5, a combustion cover 6, a combustion cup 7, a linear motion mechanism 8 and a combustion cover bottom plate 9.

The rack 1 is a square frame structure and is formed by welding steel square pipes, and the upper plate surface and the lower plate surface of the rack 1 are provided with round holes, so that the rack is convenient to be matched with a smoke exhaust pipe and a piston.

The middle of the frame body 2 is provided with a round hole which is convenient to be matched with a smoke exhaust pipe.

The residual heat after the piston is heated by the acetylene flame needs to be discharged to an external space through the movable smoke exhaust pipe 4 and the smoke exhaust pipe 3. Waste gas after the acetylene flame heats the piston needs to pass through the movable smoke exhaust pipe 4, the smoke exhaust pipe 3 is exhausted to an external space, the smoke exhaust pipe 3 is placed above the movable smoke exhaust pipe 4, the inner diameter of the smoke exhaust pipe 3 is slightly larger than the outer diameter of the movable smoke exhaust pipe 4, and relative movement of the smoke exhaust pipe and the movable smoke exhaust pipe is facilitated.

The design of combustion cover 6 is square, and the centre is opened has circular entrance to a cave, and the removal is discharged fume the pipe 4 and is placed on it, and the cooperation of burning cup 7 below and circular entrance to a cave, four faces of 6 upper parts of combustion cover incline certain angle inwards, all opens the round hole on four inclined planes and makes things convenient for the nozzle to stretch into and carry out the oil spout. The flame temperature is changed by adjusting the amount of the sprayed acetylene and the amount of the sprayed oxygen, and the real working environment temperature of the piston is simulated.

The 4 nozzles are arranged in a bias mode, so that vortex can be generated in the combustion chamber, fuel oil and air can be mixed and combusted fully, flame is diffused, and the temperature in the combustion chamber is distributed uniformly.

The smoke exhaust pipe 3 and the movable smoke exhaust pipe 4 are made of steel pipes, so that high-temperature flame cannot damage the structure of the combustion chamber; the combustion cover 6 and the combustion cup 7 are made of ceramics because they are in direct contact with the flame.

The linear motion mechanisms 8 are arranged on two sides of the rack 1, the linear motion mechanisms 8 are connected with the combustion cover bottom plate 9, and partial parts of the combustion chamber can be subjected to position adjustment through the lifting mechanisms

4 heat-insulating slots are opened on the bottom plate 9 of the combustion cover, so that heat transfer inside and outside the heat-insulating slots is effectively buffered, and a heat-insulating effect is achieved.

As shown in figure 1, a circular hole is formed in the upper plate surface of a rack 1 at a corresponding position to be matched with a smoke exhaust pipe 3, a circular hole is formed in the lower plate surface to be matched with a combustion cover 6, a piston can be pushed into a combustion chamber from the lower plate surface hole, a linear motion mechanism 8 is connected with a combustion cover bottom plate 9, the positions of part of parts of the combustion chamber are changed through four groups of ball screws in the linear motion mechanism 8, the distance from a nozzle to the combustion chamber is adjusted, and stability of heat transfer and heat dissipation is guaranteed.

As shown in figure 2, among the combustion chamber structure, the smoke exhaust pipe 3 is used for heat exhaust, and waste gas generated after acetylene flame heating a piston needs to be exhausted to an external space through the smoke exhaust pipe 3, otherwise, a laboratory bench can break down due to continuous high temperature, and the smoke exhaust pipe 3 is made of steel pipes in order to prevent high-temperature flame from damaging the combustion chamber structure. Furthermore, for the parts of the combustion cover 6 and the combustion cup 7 that are in contact with the flame, these two parts will be made of ceramic. The offset angle of the nozzle is adjusted according to actual needs, so that vortex is generated in the combustion chamber, and the diffusion of flame and the uniformity of temperature are facilitated. The hole in which the nozzle 5 is installed needs to be sealed with a fire and explosion proof paste after the nozzle angle is determined, thereby preventing flames from escaping the combustion chamber.

Claims

1. The utility model provides a burning analogue means for vehicle engine piston heat load experiment which characterized by: including the rack, the chimney, remove the chimney, the combustion cover bottom plate, the burning cup, linear motion mechanism, the top of rack sets up the face, the below of rack sets up down the face, the combustion cover bottom plate is located face top down, a offside installation linear motion mechanism of rack, linear motion mechanism connects the combustion cover bottom plate, the burning cover is located the combustion cover bottom plate, the burning cover is connected to the bottom of removing the pipe of discharging fume, the top of removing the pipe of discharging fume is located the pipe of discharging fume, the last face of rack is passed at the top of pipe of discharging fume and outside it, the burning cup is located the combustion cover below, install the nozzle on the combustion cover.

2. The combustion simulation device for the heat load test of the vehicular engine piston according to claim 1, wherein: the outer ring of the combustion cover is square, a circular hole is formed in the middle of the combustion cover, the bottom of the movable smoke exhaust pipe is located in the upper portion of the circular hole, and the top of the combustion cup is located in the lower portion of the circular hole.

3. The combustion simulation device for the heat load experiment of the piston of the vehicle engine as claimed in claim 2, wherein: four faces on the upper part of the outer ring of the combustion cover are inwards inclined to form four inclined planes, and the four inclined planes are all provided with round holes for installing nozzles.

4. The combustion simulation device for the heat load test of the vehicular engine piston according to claim 3, wherein: the nozzle and the round hole for installing the nozzle are sealed by fireproof and explosion-proof mud.

5. The combustion simulation device for the heat load test of the vehicular engine piston according to claim 1, wherein: the top of the smoke exhaust tube penetrates through the rack body before penetrating through the upper plate surface.

6. The combustion simulation device for the heat load test of the piston of the vehicle engine as claimed in claim 1, wherein: the nozzles are each offset so as to generate a vortex.

7. The combustion simulation device for the heat load test of the vehicular engine piston according to claim 1, wherein: the smoke exhaust pipe and the movable smoke exhaust pipe are both made of steel pipes, and the combustion cover and the combustion cup are both made of ceramics.

8. The combustion simulation device for the heat load test of the piston of the vehicle engine as claimed in claim 1, wherein: four heat insulation grooves are arranged on the bottom plate of the combustion cover.