A direct contact high temperature cooling system based on non-ignition diesel engine

Abstract

The present invention discloses a direct contact high-temperature cooling system based on a non-ignition diesel engine, comprising a cylinder block, a measuring subsystem and a cooling flow path; the cylinder block comprises a cylinder head, a cylinder wall and a piston removed from an engine to be measured; and a high-temperature steady-state heat source is arranged at the bottom of the cylinder head; a plurality of holes are opened from the cylinder block cooling cavity toward the side wall of the cylinder wall as measuring points at the cylinder wall, corresponding in sequence to the positions of the junction of the cylinder wall and the piston, the first piston ring groove, the first piston ring land and the second piston ring groove when the piston is at the bottom dead center; a fourth temperature sensor is arranged in the hole located at the junction of the cylinder wall and the piston; a third temperature sensor is respectively arranged in the remaining holes; a plurality of holes are evenly distributed on the inner wall of the piston top as measuring points of the piston; the holes at at least two measuring points do not penetrate the piston top surface; a fifth temperature sensor is respectively arranged in the holes at the piston measuring points; and the cooling flow path is used to allow coolant to flow through the cylinder block cooling cavity.

Description

Technical Field

[0001] The present invention belongs to the field of diesel engine thermal load measurement, and specifically relates to a method for cooling a diesel engine operating under heavy load using a high-temperature heat source while passing coolant through the cylinder, and measuring the heat exchange amount and temperature field in the cylinder. Background Art

[0002] As a power unit for special equipment, high-power density engines often work in a relatively harsh environment, which is specifically reflected in the higher explosion pressure (20MPa) and in-cylinder temperature (1000℃). If experimental methods are used to explore the impact of specific parameters on heat transfer, it is necessary to establish corresponding operating benches and test systems. When reducing heat transfer is the main goal, we need to pay attention to the average heat exchange of the entire high-temperature cooling system. The heat exchange of the high-temperature cooling system is determined by the coolant temperature and the coolant flow rate. Generally, the lower the coolant temperature, the greater the heat exchange of the cooling system. The greater the coolant flow rate, the greater the heat exchange of the system.

[0003] Coolant is a liquid capable of normal heat exchange at temperatures up to 1000°C. During operation, it is pumped through a flow channel into the cylinder block, where it comes into direct contact with the cylinder wall and piston, resulting in convective heat transfer. This allows for thermal balance testing of the entire engine, determining the heat transfer rates of the water, air, and oil systems within controlled boundaries and quantifying the macroscopic heat distribution of the diesel engine.

[0004] CN109578126A discloses a high- and low-temperature dual-circulation cooling system for hybrid vehicles, comprising a high- and low-temperature circulation system. This system can further optimize the thermostat design to improve the cooling medium's heating rate and mixing uniformity, but it cannot test or study the high-temperature cooling heat transfer performance of a non-ignition diesel engine cylinder. Summary of the Invention

[0005] The purpose of the present invention is to overcome the deficiencies in the prior art and to propose a high-temperature cooling heat transfer system based on direct heat exchange and convective heat exchange in the cylinder and a method for constructing the same. The method uses coolant as the coolant, which can cool the engine wall and piston by convective heat exchange and direct heat exchange. The coolant is introduced into the cylinder through an external cooling chamber above the engine, and an outlet is opened on the side of the cylinder body to analyze the heat exchange in the cylinder by analyzing the coolant temperature difference and flow rate at the inlet and outlet. The temperature of the single-cylinder engine using the present invention must be high enough, and the coolant must be in full contact with the wall and piston for heat exchange.

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

[0007] A direct contact high temperature cooling system based on a non-ignition diesel engine includes a cylinder block, a measurement subsystem and a cooling flow path;

[0008] The cylinder block includes a cylinder head, cylinder wall, and piston removed from the engine to be measured; a high-temperature steady-state heat source is provided in a space enclosed by the cylinder head, cylinder wall, and piston, and a hole is provided in the cylinder head for connecting a wire of the high-temperature steady-state heat source; and a cylinder block cooling chamber is provided on an outer wall closely adjacent to the cylinder wall;

[0009] Multiple holes are opened from the cylinder cooling cavity toward the side wall of the cylinder wall as measuring points on the cylinder wall, corresponding to the positions of the junction of the cylinder wall and the piston when the piston is at the bottom dead center, the first piston ring groove, the first piston ring land, and the second piston ring groove; a fourth temperature sensor is installed in the hole located at the junction of the cylinder wall and the piston; and third temperature sensors are installed in the remaining holes respectively.

[0010] The inner wall of the top of the piston is evenly distributed with a plurality of holes as measuring points of the piston; the holes at at least two measuring points do not penetrate the top surface of the piston; the holes at the measuring points of the piston are respectively provided with fifth temperature sensors;

[0011] The cooling flow path includes a water tank, a radiator, a variable frequency water pump, a throttle valve, a cooling tower, and a cylinder cooling cavity connected in sequence by pipelines; the coolant from the water tank flows through the radiator, the variable frequency water pump, the throttle valve, the cooling tower, and the cylinder cooling cavity in sequence, and then flows back to the water tank from the outlet of the cylinder cooling cavity;

[0012] The inlet and outlet of the cylinder cooling chamber are respectively located on opposite side walls of the cylinder wall, the outlet of the cylinder cooling chamber is located near the flange of the high-temperature steady-state heat source, and the inlet of the cylinder cooling chamber is located between the fourth temperature sensor and the third temperature sensor;

[0013] The measurement subsystem includes a temperature sensor assembly and a flow meter; the flow meter is located at the water outlet of the variable frequency water pump; the temperature sensor assembly includes a first temperature sensor, a second temperature sensor, a third temperature sensor, a fourth temperature sensor and a fifth temperature sensor; the first temperature sensor is located at the entrance of the cylinder cooling chamber and is used to measure the temperature of the coolant before entering the cylinder cooling chamber, the second temperature sensor is located at the outlet of the cylinder cooling chamber and is used to measure the temperature flowing out of the cylinder cooling chamber, and multiple third temperature sensors are respectively located in the holes opened on the cylinder wall at the first piston ring groove, the first piston ring land, and the second piston ring groove, and are used to measure the cylinder wall temperature at the corresponding position of the piston and the internal temperature of the cylinder at the piston position, the fourth temperature sensor is located on the cylinder wall and is opened at the junction of the cylinder wall and the piston top when the piston is at the bottom dead center, measuring the cylinder wall temperature at the junction of the piston top and the cylinder wall, and the fifth temperature sensor is set inside the inner wall of the piston top surface, measuring the temperature of different positions on the piston top surface; and each temperature sensor is electrically connected to the temperature measuring instrument.

[0014] Furthermore, the measurement subsystem also includes a coolant temperature controller and a heating rod temperature control device; the coolant temperature controller includes a heater for controlling the water tank temperature at a constant temperature; the heating rod temperature control device is used to control the temperature of the high-temperature steady-state heat source.

[0015] Furthermore, the first temperature sensor, the second temperature sensor, the third temperature sensor, the fourth temperature sensor and the fifth temperature sensor are all thermocouple temperature sensors.

[0016] Furthermore, two oppositely arranged first cylinder wall measuring points and a fourth cylinder wall measuring point are set at the first piston ring groove, two oppositely arranged second cylinder wall measuring points and a fifth cylinder wall measuring point are set at the first piston ring land, and two oppositely arranged third cylinder wall measuring points and a sixth cylinder wall measuring point are set at the second piston ring groove; wherein, the first cylinder wall measuring point, the second cylinder wall measuring point and the third cylinder wall measuring point are located on the same side as the ninth cylinder wall measuring point, and they reach the outer surface of the cylinder wall after passing through the cylinder cooling cavity; the fourth cylinder wall measuring point, the fifth cylinder wall measuring point and the sixth cylinder wall measuring point are located on opposite sides of the cylinder wall, and the corresponding threaded holes are through holes, that is, they pass through the cylinder cooling cavity and penetrate the cylinder wall; a third temperature sensor is fixedly set in the threaded holes at the first cylinder wall measuring point, the second cylinder wall measuring point, the third cylinder wall measuring point, the fourth cylinder wall measuring point, the fifth cylinder wall measuring point and the sixth cylinder wall measuring point.

[0017] Furthermore, five threaded holes are provided on the inner wall of the top of the piston as measuring points at the piston, including a first piston measuring point, a second piston measuring point, a third piston measuring point, a fourth piston measuring point and a fifth piston measuring point. The third piston measuring point is located at the center of the top of the piston, and the remaining measuring points are circumferentially distributed on the top of the piston around the third piston measuring point. The threaded holes at the third and fifth piston measuring points are through holes, and the threaded holes at the first, second and fourth piston measuring points are blind holes. The distances of these three measuring points from the top surface of the piston are arranged from largest to smallest, namely the first measuring point, the second measuring point and the fourth measuring point. A fifth temperature sensor is respectively provided in the threaded holes at the first, second, third, fourth and fifth measuring points.

[0018] Furthermore, the working process of the direct contact high-temperature cooling heat transfer system based on the non-ignition diesel engine includes:

[0019] When in use, turn on the variable frequency water pump, open the throttle valve to maximize the coolant flow, and close the radiator; circulate the coolant inside the cooling flow path, then turn on the heating rod in the water tank to heat the coolant in the water tank to 150°C, then energize the high-temperature steady-state heat source to heat the inside of the cylinder, and turn on the radiator at the same time;

[0020] When the coolant flows through the cylinder cooling cavity, it exchanges heat with the heat generated by the outer surface of the cylinder liner, causing the coolant temperature in the cylinder cooling cavity to rise. The radiator reduces the coolant temperature to 150°C and flows back into the water tank. It then enters the cooling cavity through the variable frequency water pump and continues to circulate.

[0021] When the high-temperature steady-state heat source reaches a preset limit temperature, the temperature sensor assembly is used to measure the temperature of the cooling chamber water outlet and water inlet, the piston measuring point temperature and the cylinder wall measuring point temperature.

[0022] Furthermore, the direct contact high-temperature cooling and heat transfer system based on the non-ignition diesel engine needs to be pre-treated before use, including:

[0023] The cylinder head, cylinder wall and piston of the engine to be measured are disassembled, and holes are punched on the cylinder head, cylinder wall and piston to set cylinder wall measuring points and piston measuring points; the cylinder cooling cavity is tightly fitted on the outer surface of the cylinder wall; and the high-temperature steady-state heat source is set in the space enclosed by the cylinder head, cylinder wall and piston;

[0024] Reassemble the cylinder head, cylinder wall and piston, and pull the piston to the bottom dead center; connect the cooling flow path and ensure the air tightness of the flow path, and the high-temperature steady-state heat source is set in the space surrounded by the cylinder head, cylinder wall and piston.

[0025] Furthermore, when the variable frequency water pump is not turned on, the third temperature sensor, the fourth temperature sensor and the fifth temperature sensor located at the cylinder wall are used to measure the temperatures at different positions on the cylinder wall and inside the cylinder, as well as the temperatures at various positions on the top surface of the piston; after the variable frequency water pump is turned on, the coolant in the cooling flow path is circulated, and the first temperature sensor and the second temperature sensor located at the water inlet of the cylinder cooling cavity and the water outlet of the cylinder are used to measure the temperatures, and the third temperature sensor, the fourth temperature sensor and the fifth temperature sensor located at the cylinder wall are used to measure the temperatures at different positions on the cylinder wall and inside the cylinder, as well as the temperatures at different positions on the top surface of the piston.

[0026] Compared with the prior art, the technical solution of the present invention has the following beneficial effects:

[0027] The present invention can simulate the high-temperature combustion environment of a non-ignition diesel engine and conduct high-temperature cooling and heat transfer performance testing and research on its cylinder body;

[0028] The high-temperature steady-state heat source in the present invention is specifically designed for the special high-temperature working conditions of non-ignition diesel engine cylinders, meeting the requirements of its cooling and heat transfer performance testing;

[0029] Moreover, it is possible to conduct high-temperature cooling and heat transfer performance tests and research on different parts of the cylinder body, such as piston ring grooves, piston ring lands, etc., to provide data support for cylinder body structure optimization. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 Schematic diagram of the structure of the high-temperature cooling and heat transfer system based on a non-ignition diesel engine of the present invention;

[0031] Figure 2a is a schematic top view of the piston of the high-temperature cooling heat transfer system of the present invention, showing the distribution of measuring points on the inner wall of the top of the piston; Figure 2b yes Figure 2a A side cross-sectional view of

[0032] Figure 3 is a schematic diagram of the cylinder side wall opening of the high-temperature cooling heat transfer system;

[0033] Figure 4 This is a flow chart for constructing the diesel engine high-temperature cooling and heat transfer system of the present invention.

[0034] in,

[0035] 1: Cylinder head; 2: Cylinder wall; 3: Piston; 4: High-temperature steady-state heat source; 5: Water tank; 6: First temperature sensor; 7: Second temperature sensor; 8: Third temperature sensor; 9: Temperature measuring instrument; 10: Radiator; 11: Variable frequency water pump; 12: Throttle valve; 13: Cylinder cooling chamber; 14: Fourth temperature sensor; 15: Fifth temperature sensor; 16: First piston measuring point; 17: Second piston measuring point; 18: Third piston measuring point; 19: Fourth piston measuring point; 20: Fifth piston measuring point; 81: First cylinder wall measuring point; 82: Second cylinder wall measuring point; 83: Third cylinder wall measuring point; 84: Fourth cylinder wall measuring point; 85: Fifth cylinder wall measuring point; 86: Sixth cylinder wall measuring point; 87: Seventh cylinder wall measuring point; 88: Eighth cylinder wall measuring point; 141: Ninth cylinder wall measuring point. DETAILED DESCRIPTION

[0036] In order to make the purpose, technical solutions, beneficial effects and significant improvements of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention are clearly and completely described below in conjunction with the drawings provided in the examples of the present invention. Obviously, all the described embodiments are only partial embodiments of the present invention, rather than all embodiments; based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0037] like Figure 1As shown, a direct contact high-temperature cooling heat transfer system based on a non-ignition diesel engine includes a cylinder block, a measurement subsystem and a cooling flow path. The cylinder block includes a cast iron cylinder head 1, a cast iron cylinder wall 2, an aluminum alloy piston 3 and a high-temperature steady-state heat source 4, and a cylinder cooling cavity 13 is sleeved on the outer wall of the cylinder head 1. The cylinder cooling cavity 13 is made of cast iron material with good airtightness and is painted on the surface to prevent rust. The cast iron cylinder head 1, cast iron cylinder wall 2 and aluminum alloy piston 3 are removed from a single-cylinder diesel engine with a diameter of 130 mm to be measured. After the cylinder head 1 is removed from the single-cylinder diesel engine, the connected intake, exhaust and fuel injection systems are removed. Only a hole is opened on the top of the cylinder head 1 with a hole diameter of 7-8 mm and a hole depth of 50 mm. The center of the circle is located at the center of the cylinder head 1 for connecting the wire of the high-temperature steady-state heat source 4.

[0038] like Figure 3 As shown, seven threaded holes need to be opened at the level of the cylinder axis from the cylinder cooling chamber 13 to the side wall of the cylinder wall 2 as measuring points on the cylinder wall, corresponding to the positions of the junction of the cylinder wall and the piston when the piston is at the bottom dead center, the first piston ring groove, the first piston ring land, and the second piston ring groove; among them, the ninth cylinder wall measuring point 141 is located at the junction of the cylinder wall and the piston when the piston is at the bottom dead center, and the corresponding threaded hole is a blind hole, which passes through the cylinder cooling chamber 13 and reaches the outer surface of the cylinder wall 2 (and does not extend into the cylinder wall), and the fourth temperature sensor 14 is fixedly installed in the threaded hole at the ninth cylinder wall measuring point.

[0039] Two opposing first and fourth cylinder wall measuring points 81 and 84 are set at the first piston ring groove, two opposing second and fifth cylinder wall measuring points 82 and 85 are set at the first piston ring land, and two opposing third and sixth cylinder wall measuring points 83 and 86 are set at the second piston ring groove. The first, second, and third cylinder wall measuring points 81, 82, and 83 are located on the same side as the ninth cylinder wall measuring point 141, and the threaded holes located there are also blind holes, passing through the cylinder cooling cavity 13 and reaching the outer surface of the cylinder wall 2 (without extending into the cylinder wall). The fourth, fifth, and sixth cylinder wall measuring points 84, 85, and 86 are located on opposite sides of the cylinder wall, and the corresponding threaded holes are through holes, i.e., they pass through the cylinder cooling cavity 13 and penetrate the cylinder wall 2. A third temperature sensor 8 is fixedly mounted in each threaded hole at the first cylinder wall measuring point 81, the second cylinder wall measuring point 82, the third cylinder wall measuring point 83, the fourth cylinder wall measuring point 84, the fifth cylinder wall measuring point 85, and the sixth cylinder wall measuring point 86. Furthermore, the six third temperature sensors 8 and the fourth temperature sensor 14 are all electrically connected to the temperature measuring instrument 9.

[0040] In particular, the three third temperature sensors 8 located on the same side as the fourth temperature sensor 14 pass through the cylinder cooling cavity 13 to reach the outer surface of the cylinder wall, and are used to measure the temperature of the cylinder wall at the corresponding position of the piston; the three third temperature sensors 8 located on the opposite side of the cylinder wall pass through the cylinder cooling cavity 13 and the cylinder wall 2 in turn, and the ends of the third temperature sensors extend into the interior of the cylinder, and are used to measure the internal temperature of the cylinder at the piston position.

[0041] like Figure 2a-2b As shown, the inner wall of the top of the piston 3 is provided with five threaded holes as measuring points on the piston, including the first piston measuring point 16, the second piston measuring point 17, the third piston measuring point 18, the fourth piston measuring point 19 and the fifth piston measuring point 20. The third piston measuring point 18 is located at the center of the top of the piston, and the remaining measuring points are distributed circumferentially around the third piston measuring point on the top of the piston. Figure 2b As shown, the threaded holes at the third and fifth piston measuring points 18 and 20 are through holes, while the threaded holes at the first, second, and fourth piston measuring points 16, 17, and 19 are blind holes. These three measuring points are ranked from greatest to least distant from the piston top surface: first measuring point 16, second measuring point 17, and fourth measuring point 19. A fifth temperature sensor 15 is disposed within each of the threaded holes at the first, second, third, fourth, and fifth measuring points 16, 17, 18, and 19, respectively. The bottom of each fifth temperature sensor 15 is electrically connected to the temperature measuring instrument 8 via a circuit that passes through the bottom of the piston.

[0042] After the cylinder head 1 is machined, the cylinder head 1, cylinder wall 2, and piston 3 are reassembled, and the high-temperature steady-state heat source 4 is fixedly mounted on the inner wall of the cylinder head 1, thereby positioning the high-temperature steady-state heat source 4 within the combustion chamber formed by the cylinder head 1, cylinder wall 2, and piston 3. A cylinder cooling chamber 13 is sleeved onto the outer wall of the cylinder liner. The interior space of the cylinder cooling chamber 13 is 10 mm thick, and the outer wall is 5 mm thick. The inlet of the cylinder cooling chamber 13 is located on the side wall of the cylinder liner 2, between the third temperature sensor 8 and the fourth temperature sensor 14. The cylinder cooling chamber 13 is also equipped with a bleed valve. A cooling tower is screwed to the top of the cylinder head.

[0043] The high-temperature steady-state heat source 4 is used to simulate the operation of a thermodynamic diesel engine and comprises two opposing flanges and ten single 320W heating rods. The ends of the ten heating rods are equidistantly fixed to the flanges. The top of the flange is fixed to the inner wall of the cylinder head 1. The flange has a diameter of 130 mm and a thickness of 2 mm. The heating rods have a diameter of 16 mm and a length of 100 mm. Two wires extend from the center of the flange and extend through holes in the cylinder head 1. The wires are connected to thermocouple temperature sensors and heating rod temperature control devices to control the heating rod temperature. The heating rods are powered by a 220V AC power supply.

[0044] The heating rod temperature control device is connected to the thermocouple temperature sensor and the high-temperature steady-state heat source 4 in sequence, and is used to form feedback on the power supply of the heating rod so that the temperature of the heating rod can be controlled.

[0045] The cooling flow path includes a water tank 5, a radiator 10, a variable frequency water pump 11, a throttle valve 12, an external cooling tower, and a cylinder cooling chamber 13 connected in sequence by pipelines; the coolant from the water tank 5 flows into the variable frequency water pump 11 through the pipeline, and the outlet water of the variable frequency water pump 11 is provided with a throttle valve 12, and the outlet of the throttle valve 12 is connected to the inlet of the cooling tower through a pipeline. The cooling tower is located on the top of the cylinder head (not shown in the figure) for accommodating coolant, and the outlet of the cooling tower is connected to the inlet of the cylinder cooling chamber 13, and the outlet of the cylinder cooling chamber 13 is connected to the liquid inlet of the water tank 5 through a pipeline; and the inlet and outlet of the cylinder cooling chamber 13 are respectively located on the opposite side walls of the cylinder wall, the outlet of the cylinder cooling chamber 13 is located near the flange of the high-temperature steady-state heat source 4, and the inlet of the cylinder cooling chamber is located between the fourth temperature sensor and the third temperature sensor. The radiator 10 is an air-cooled radiator. A heating rod and an AC contactor are provided in the water tank 5. A coolant temperature controller is connected to the AC contactor and the heating rod in sequence to stabilize the coolant temperature in the water tank at 150°C.

[0046] The measurement subsystem includes a temperature sensor assembly, a temperature measuring instrument, a flowmeter, a thermostat assembly, and a control module. A flowmeter is installed at the outlet of the variable frequency water pump 11 to measure the flow of coolant into the cooling chamber. The thermostat assembly includes a coolant temperature controller for controlling the water tank temperature and a heating rod temperature control device for controlling the temperature within the cylinder. The temperature sensor assembly includes a first temperature sensor 6, a second temperature sensor 7, a third temperature sensor 8, a fourth temperature sensor 14 and a fifth temperature sensor 15. The first temperature sensor 6 is located at the entrance of the cylinder cooling chamber 13 and is used to measure the temperature of the coolant before entering the cylinder cooling chamber 13. The second temperature sensor 7 is located at the outlet of the cylinder cooling chamber 13 and is used to measure the temperature flowing out of the cylinder cooling chamber 13. Multiple third temperature sensors 8 are respectively located in holes opened on the cylinder wall at the first piston ring groove, the first piston ring land, and the second piston ring groove, and are used to measure the temperature at different positions of the piston and the junction of the piston top and the cylinder wall. The fourth temperature sensor 14 is located on the cylinder wall and is opened at the junction of the cylinder wall and the piston top when the piston is at the bottom dead center. The fifth temperature sensor 15 is opened on the inner wall of the piston top surface.

[0047] Each of the temperature sensors is connected to a temperature measuring instrument, an output end of the temperature measuring instrument is connected to the control module, and the control module receives data from the temperature measuring instrument and data from the flow meter for subsequent data monitoring and regularity analysis.

[0048] The first, second, third, fourth and fifth temperature sensors are thermocouple temperature sensors, each of which is respectively arranged in a temperature measurement point, and the thermocouple test wires of the thermocouple temperature sensors are connected to a multi-interface temperature measuring instrument.

[0049] like Figure 4 As shown, the working process of the direct contact high-temperature cooling heat transfer system of the non-ignition diesel engine includes:

[0050] Pre-treat the cylinder block and arrange temperature sensors: Remove the cylinder head 1 from the engine, dismantle the original engine's intake, exhaust, and fuel injection systems, and weld the gaps using the same material as the cylinder head 1 to prevent coolant leakage. A hole is drilled in the center of the cylinder head to allow the heat source line to pass through. Seven threaded holes are drilled in the cylinder wall 2, parallel to the cylinder axis, as measuring points on the cylinder wall. These holes correspond to the intersection of the cylinder wall and piston, the first piston ring groove, the first piston land, and the second piston ring groove, respectively, when the piston is at bottom dead center. A fourth temperature sensor 14 is installed in the threaded hole at the intersection of the cylinder wall and piston when the piston is at bottom dead center. A third temperature sensor 8 is installed at the first piston ring groove, the first piston land, and the second piston ring groove. This third temperature sensor 8 is electrically connected to a temperature measuring instrument 9 via wiring. The threaded holes at the first, second, and third cylinder wall measuring points 81, 82, and 83 extend through the cylinder cooling cavity 13 and reach the outer surface of the cylinder wall 2. The fourth cylinder wall measuring point 84 , the fifth cylinder wall measuring point 85 and the sixth cylinder wall measuring point 86 are located on opposite sides, and the threaded holes therein are through holes that penetrate the cylinder cooling cavity 13 and the cylinder wall 2 .

[0051] Five threaded holes are provided on the inner wall of the top of the piston 3 as piston measuring points. A fifth temperature sensor 15 is respectively provided in the first piston measuring point 16, the second piston measuring point 17, the third piston measuring point 18, the fourth piston measuring point 19 and the fifth piston measuring point 20. The bottom of the fifth temperature sensor 15 is electrically connected to the temperature measuring instrument 9 after passing through the bottom of the piston through a line.

[0052] The first temperature sensor 6 is located at the entrance of the cylinder cooling chamber 13, and the second temperature sensor 7 is located at the outlet of the cylinder cooling chamber 13; and the thermocouple test line of the temperature sensor is connected to the temperature measuring instrument 9; a flow meter is set at the water outlet of the variable frequency water pump 11.

[0053] Reassemble the cylinder head 1, cylinder wall 2, and piston 3, and pull the piston 3 to the bottom dead center; and place the high-temperature steady-state heat source 4 in the space enclosed by the cylinder head 1, cylinder wall 2, and piston 3, and connect the energized end of the heating tube of the high-temperature steady-state heat source 4 to a 220V AC power supply;

[0054] After ensuring the cooling flow path is airtight, fill the water tank with coolant. Install the throttle valve and flowmeter on the circulating pump. Use stainless steel piping to connect the circulating pump, water tank, diesel engine block cooling chamber, and external cooling chamber. After verifying the system's airtightness, pour coolant into the water tank, insert a constant-temperature heater, and connect the thermostat and AC contactor. Without the variable-frequency water pump running, use the third, fourth, and fifth temperature sensors 8, 14, and 15 located on the cylinder wall to measure temperatures at various locations on the cylinder wall, within the cylinder, and at various locations on the piston top surface.

[0055] First, the variable frequency water pump 11 is turned on. At this time, the throttle valve 12 is opened to allow the coolant to reach the maximum flow rate. The radiator 10 is closed at this time, allowing the coolant in the cooling flow path to circulate. Then, the heating rod in the water tank is turned on to heat the coolant in the water tank to 150°C. After the temperature is constant, the high-temperature steady-state heat source 4 is energized to heat the inside of the cylinder body. At the same time, the radiator 10 is turned on. The purpose of the radiator is to reduce the temperature of the coolant after the coolant circulation back to 150°C, ensuring that the inlet temperature is always 150°C.

[0056] The coolant flows through the cylinder cooling chamber 13 in the cooling flow path, exchanging heat with the heat generated by the outer surface of the cylinder liner, causing the coolant temperature in the cylinder cooling chamber 13 to rise. The radiator 10 in the pipe between the cooling chamber outlet and the water tank reduces the coolant temperature to 150°C and flows back into the water tank. It then enters the cooling chamber through the variable frequency water pump 11 and continues to circulate.

[0057] Until the high-temperature steady-state heat source 4 reaches the preset temperature of 800°C (limit temperature) and the entire system is in a steady state, the first temperature sensor 6 and the second temperature sensor 7 located at the water inlet of the cylinder cooling chamber 13 and the water outlet of the cylinder are used to measure the temperature, and the third temperature sensor 8, the fourth temperature sensor 14 and the fifth temperature sensor 15 located at the cylinder wall are used to measure the temperature at different positions on the cylinder wall and in the cylinder, as well as the temperature at different positions on the top surface of the piston, and the measured temperature is transmitted to the control module through the temperature measuring instrument 9 for analysis.

[0058] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents, and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention. Non-essential improvements, adjustments or replacements made by those skilled in the art based on the contents of this specification are all within the scope of protection required by the present invention.

Claims

1. A direct contact high temperature cooling system based on a non-ignition diesel engine, characterized in that: Includes cylinder body, measurement subsystem and cooling flow path; The cylinder body comprises a cylinder head (1), a cylinder wall (2) and a piston (3) removed from the engine to be measured; a high-temperature steady-state heat source (4) is provided in a space enclosed by the cylinder head (1), the cylinder wall (2) and the piston (3), and a hole is provided on the cylinder head for connecting a wire of the high-temperature steady-state heat source (4); and a cylinder cooling cavity (13) is provided on an outer wall closely attached to the cylinder wall (2); A plurality of holes are provided from the cylinder cooling cavity (13) toward the side wall of the cylinder wall (2) as measuring points on the cylinder wall, corresponding to the positions of the junction between the cylinder wall and the piston, the first piston ring groove, the first piston ring land, and the second piston ring groove when the piston is at the bottom dead center; a fourth temperature sensor (14) is provided in the hole at the junction between the cylinder wall and the piston; and third temperature sensors (8) are provided in the remaining holes respectively; The inner wall of the top of the piston is evenly distributed with a plurality of holes as measuring points of the piston; the holes at at least two measuring points do not penetrate the top surface of the piston; and fifth temperature sensors (15) are respectively provided in the holes at the measuring points of the piston; The cooling flow path includes a water tank (5), a radiator (10), a variable frequency water pump (11), a throttle valve (12), a cooling tower, and a cylinder cooling chamber (13) connected in sequence through pipelines; the coolant from the water tank (5) flows through the radiator (10), the variable frequency water pump (11), the throttle valve (12), the cooling tower, and the cylinder cooling chamber (13) in sequence, and then flows back to the water tank from the outlet of the cylinder cooling chamber; The inlet and outlet of the cylinder cooling cavity (13) are respectively located on opposite side walls of the cylinder wall, the outlet of the cylinder cooling cavity (13) is located near the flange of the high-temperature steady-state heat source (4), and the inlet of the cylinder cooling cavity (13) is located between the fourth temperature sensor and the third temperature sensor; The measuring subsystem includes a temperature sensor assembly and a flow meter; the flow meter is located at the water outlet of the variable frequency water pump (11); the temperature sensor assembly includes a first temperature sensor (6), a second temperature sensor (7), a third temperature sensor (8), a fourth temperature sensor (14) and a fifth temperature sensor (15); the first temperature sensor (6) is located at the inlet of the cylinder cooling chamber (13) and is used to measure the temperature of the coolant before entering the cylinder cooling chamber (13); the second temperature sensor (7) is located at the outlet of the cylinder cooling chamber (13) and is used to measure the temperature of the coolant from the cylinder cooling chamber (13) outflow temperature, a plurality of the third temperature sensors (8) are respectively located on the cylinder wall in holes opened at the first piston ring groove, the first piston ring land, and the second piston ring groove, and are used to measure the cylinder wall temperature at the corresponding position of the piston and the internal temperature of the cylinder body at the piston position, the fourth temperature sensor (14) is located on the cylinder wall and opened at the junction of the cylinder wall and the piston top when the piston is at the bottom dead center, and measures the cylinder wall temperature at the junction of the piston top and the cylinder wall, the fifth temperature sensor (15) is set in the inner wall of the piston top surface, and measures the temperature at different positions of the piston top surface; and each temperature sensor is electrically connected to the temperature measuring instrument.

2. The direct contact high temperature cooling system based on a non-ignition diesel engine according to claim 1, characterized in that: The measurement subsystem further comprises a coolant temperature controller and a heating rod temperature control device; the coolant temperature controller comprises a heater for controlling the temperature of the water tank at a constant temperature; the heating rod temperature control device is used to control the temperature of the high-temperature steady-state heat source (4).

3. The direct contact high temperature cooling system based on a non-ignition diesel engine according to claim 1, characterized in that: The first temperature sensor (6), the second temperature sensor (7), the third temperature sensor (8), the fourth temperature sensor (14) and the fifth temperature sensor (15) are all thermocouple temperature sensors.

4. The direct contact high temperature cooling system based on a non-ignition diesel engine according to claim 1, characterized in that: Two first cylinder wall measuring points (81) and a fourth cylinder wall measuring point (84) are arranged oppositely at the first piston ring groove, two second cylinder wall measuring points (82) and a fifth cylinder wall measuring point (85) are arranged oppositely at the first piston ring land, and two third cylinder wall measuring points (83) and a sixth cylinder wall measuring point (86) are arranged oppositely at the second piston ring groove; wherein the first cylinder wall measuring point (81), the second cylinder wall measuring point (82) and the third cylinder wall measuring point (83) are located on the same side as the ninth cylinder wall measuring point (141), which passes through the cylinder cooling The temperature sensor (8) is fixedly arranged in the threaded holes at the first cylinder wall measuring point (81), the second cylinder wall measuring point (82), the third cylinder wall measuring point (83), the fourth cylinder wall measuring point (84), the fifth cylinder wall measuring point (85) and the sixth cylinder wall measuring point (86), which are located on opposite sides of the cylinder wall and are located at corresponding threaded holes, i.e., they pass through the cylinder cooling cavity and penetrate the cylinder wall (2); a third temperature sensor (8) is fixedly arranged in the threaded holes at the first cylinder wall measuring point (81), the second cylinder wall measuring point (82), the third cylinder wall measuring point (83), the fourth cylinder wall measuring point (84), the fifth cylinder wall measuring point (85) and the sixth cylinder wall measuring point (86).

5. The direct contact high temperature cooling system based on a non-ignition diesel engine according to claim 1, characterized in that: Five threaded holes are provided on the inner wall of the top of the piston (3) as measuring points at the piston, including a first piston measuring point (16), a second piston measuring point (17), a third piston measuring point (18), a fourth piston measuring point (19) and a fifth piston measuring point (20). The third piston measuring point (18) is located at the center of the top of the piston, and the remaining measuring points are circumferentially distributed around the third piston measuring point on the top of the piston; the threaded holes at the third piston measuring point (18) and the fifth piston measuring point (20) are through holes, and the threaded holes at the first piston measuring point (16), the second piston measuring point (17) and the fourth piston measuring point (19) are blind holes, and the distances of these three measuring points from the top surface of the piston are arranged from large to small, namely the first piston measuring point (16), the second piston measuring point (17) and the fourth piston measuring point (19); a fifth temperature sensor (15) is provided in each of the threaded holes at the first piston measuring point (16), the second piston measuring point (17), the third piston measuring point (18), the fourth piston measuring point (19) and the fifth piston measuring point (20).

6. The working process of the direct contact high-temperature cooling system based on a non-ignition diesel engine according to claim 1 includes: When in use, the variable frequency water pump is turned on, the throttle valve (12) is opened to maximize the coolant flow rate, and the radiator (10) is closed; the coolant in the cooling flow path is circulated, and then the heating rod in the water tank is turned on to heat the coolant in the water tank to 150°C, and then the high temperature steady-state heat source (4) is energized to heat the inside of the cylinder, and the radiator (10) is turned on at the same time; When the coolant flows through the cylinder cooling cavity (13), it exchanges heat with the heat generated on the outer surface of the cylinder liner, causing the coolant temperature in the cylinder cooling cavity (13) to rise. The radiator (10) reduces the coolant temperature to 150°C and flows back into the water tank. The coolant then enters the cooling cavity from the variable frequency water pump (11) and continues to circulate. When the high-temperature steady-state heat source (4) reaches a preset limit temperature, the temperature sensor assembly is used to measure the temperature of the cooling chamber water outlet and water inlet, the piston measuring point temperature, and the cylinder wall measuring point temperature.

7. The direct contact high-temperature cooling system based on a non-ignition diesel engine according to claim 6 requires pretreatment of the system before use, including: The cylinder head (1), cylinder wall (2) and piston (3) of the engine to be measured are disassembled, and the cylinder head (1), cylinder wall (2) and piston (3) are punched to set cylinder wall measuring points and piston measuring points; the cylinder cooling cavity (13) is tightly mounted on the outer surface of the cylinder wall (2); and the high-temperature steady-state heat source (4) is arranged in a space enclosed by the cylinder head (1), cylinder wall (2) and piston (3); The cylinder head (1), the cylinder wall (2) and the piston (3) are reassembled, and the piston (3) is pulled to the bottom dead center; the cooling flow path is connected and the airtightness of the flow path is ensured, and the high-temperature steady-state heat source (4) is arranged in a space enclosed by the cylinder head (1), the cylinder wall (2) and the piston (3).

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