Cooling system and method of sliding vane type rotor internal combustion engine

Abstract

The invention belongs to the technical field of heat management of internal combustion engines, and relates to a cooling system and method of a sliding vane type rotor internal combustion engine, which comprises a fixed heat dissipation unit and a forced heat dissipation unit, realizes efficient heat management of the engine through a synergistic effect, and obviously improves the heat management efficiency. The fixed heat dissipation unit is composed of a plurality of differentiated heat dissipation fins and end cover heat dissipation fins which are distributed in the circumferential direction of the outer wall of the stator, and optimization design is carried out according to the four-stroke thermal load gradient. The forced heat dissipation unit comprises a circumferential cooling flow channel in the stator and a pump-fan integrated cooler embedded in an end cover, the cooling system is provided with an intelligent temperature control module, the flow of cooling liquid and the rotating speed of a fan are dynamically adjusted according to the real-time temperature, balance between heat dissipation efficiency and energy consumption is achieved, the flow is dynamically adjusted according to signals of a stator temperature sensor, and energy consumption is reduced. And compared with a constant flow mode, more energy is saved, the heat dissipation problem of the sliding vane type rotor internal combustion engine under the high heat load and friction heat generation environment is solved, and the sliding vane type rotor internal combustion engine is particularly suitable for meeting the power requirement of aircrafts under the high-altitude oxygen dilution condition.

Description

Technical Field

[0001] This invention belongs to the field of internal combustion engine thermal management technology, specifically relating to a cooling system and cooling method for a four-stroke vane rotor internal combustion engine. Background Technology

[0002] Vane-type rotor internal combustion engines, with their compact structure, high power-to-weight ratio, and low vibration, offer significant advantages in weight- and space-sensitive aerospace applications such as unmanned aerial vehicles (UAVs) and loitering munitions. However, their dynamic sealing structure (a three-dimensional friction pair of vanes, stator surfaces, and end caps) results in a complex heat transfer path, leading to extreme local heat loads far exceeding those of traditional reciprocating engines. Specifically: Asymmetric heat flow distribution; in a four-stroke cycle, the heat flow density in the compression and expansion sections can be 3 to 5 times that of the intake / exhaust sections, and the circumferential temperature gradient of the stator surface exceeds 500℃ / m, which may lead to material thermal deformation and sealing failure.

[0003] The heat concentration effect of combustion occurs when the instantaneous temperature of the combustion chamber gas exceeds 2000℃. The heat is rapidly conducted through the stator curved surface and rotor end face, forming a local high-temperature zone, which leads to a sharp drop in the strength of aluminum alloy components.

[0004] Frictional heat coupling problem: The linear velocity of the slider end face and the stator curved surface reaches 15~30m / s, and the frictional heat flux density under boundary lubrication conditions reaches 1~2MW / m², with local flash temperature rising to over 300℃, which aggravates lubrication failure and wear.

[0005] Current heat dissipation technologies struggle to balance lightweight design with high-efficiency cooling. Air cooling relies on air convection heat transfer, with a heat transfer coefficient of only 50-100 W / (m²·K), which is insufficient for high heat flux density areas exceeding 500 W / cm². Furthermore, airflow organization is significantly affected by engine speed. While water cooling can increase the heat transfer coefficient to 5000 W / (m²·K), it requires an additional water pump accounting for 5%-8% of the total weight, along with piping and radiators, significantly increasing system complexity and weight, which violates the design principles of aerospace power sources.

[0006] Therefore, there is an urgent need to develop a cooling system for a vane rotor internal combustion engine to effectively solve the problems of high local heat load and frictional heat generation. Summary of the Invention

[0007] The purpose of this invention is to provide a cooling system for a four-stroke vane rotor internal combustion engine. Through a synergistic heat dissipation mechanism, the system solves the heat dissipation problem of the vane rotor internal combustion engine under high heat load and high friction heat generation conditions. The cooling system adopts a multi-stage cooling synergy approach to achieve heat load gradient adaptation in the four-stroke working section and efficient heat conduction between the stator curved surface and the outer end face.

[0008] The objective of this invention is achieved through the following technical solution: A cooling system for a vane rotor internal combustion engine includes a forced heat dissipation unit, a fixed heat dissipation unit, and an intelligent temperature control unit 3; The forced cooling unit consists of a cooling channel 102 located inside the stator 1 of the engine block and a pump-fan integrated cooler 201 embedded in the engine end cover 2; the cooling channel 102 is located in the arc-shaped thermal arc area corresponding to the stator profile, and coolant is provided in the cooling channel 102. The fixed heat dissipation unit consists of a stator heat dissipation fin assembly and an end cover heat dissipation fin 202. The stator heat dissipation fin assembly includes multiple axially extending heat dissipation fins 101 that are evenly distributed along the circumference of the outer wall of the stator 1. Different areas and numbers of heat dissipation fins 101 are provided in the four stroke sections of the rotor engine. The end cover heat dissipation fins 202 are evenly arranged on the outer side of the rear end cover and the front end cover. The intelligent temperature control unit (3) is communicatively connected to a temperature sensor located on the stator (1) and a pump-fan integrated cooler (201) located on the engine end cover (2). The intelligent temperature control unit (3) is configured to: control the opening of a flow regulating valve located on the cooling channel (102) based on the signal from the temperature sensor; and control the operation of the pump-fan integrated cooler (201) based on the real-time temperature of the engine end cover (2).

[0009] Furthermore, the engine end cover 2 includes a rear end cover and a front end cover disposed on both sides of the engine body, and both the rear end cover and the front end cover are provided with a pump-fan integrated cooler 201; Furthermore, the cooling channel 102 is a circumferential serpentine spiral channel machined inside the stator 1 wall, with a circular cross-section and a distance of ≤5mm from the inner wall surface of the stator 1.

[0010] Furthermore, the distance between the flow channel and the inner wall surface of the stator 1 is 3.0±0.5mm, and the spiral cooling flow channel 102 obliquely surrounds the inner wall of the stator, covering the 240° wrap angle of the thermal arc area.

[0011] Furthermore, the pump-fan integrated cooler 201 is circumferentially symmetrically embedded in the annular mounting grooves of the rear end cover and the front end cover, and each set of end covers is equipped with 2 fans with a rated speed that is steplessly adjustable from 0 to 8000 rpm.

[0012] Furthermore, the coolant in the cooling channel 102 is selected from the fuel used by the engine.

[0013] Furthermore, the heat dissipation fins 101 adopt a differentiated heat load gradient distribution across four strokes, with the total fin area required for each stroke being: , in, Ai Indicates the first i Total fin area required for the stroke section; λ i Indicates the first i Stroke heat load correction factor; Q i Indicates the first i The heat dissipation during the stroke was measured through thermodynamic simulation / experiment; h This represents the overall heat transfer coefficient of the fins, which is material-dependent; Δ T i Indicates the first i The logarithmic mean temperature difference between the stator wall and the environment during the stroke.

[0014] Furthermore, the end cover heat dissipation fins 202 are radially distributed, covering the rotor end face projection area on the inner surface of the rear end cover and the front end cover.

[0015] Furthermore, the substrate of the end cover heat dissipation fins 202 is aluminum alloy, which is integrally processed by extrusion molding and is evenly distributed circumferentially.

[0016] Furthermore, when the temperature sensor signal of the intelligent temperature control unit 3 triggers the start-up and shutdown of the pump-fan integrated cooler 201, it starts when T ≥ the highest temperature of the threshold period and shuts down when T ≤ the lowest temperature of the threshold period.

[0017] Furthermore, the engine body includes a stator 1, a rotor, and vanes in the rotor slots.

[0018] Furthermore, the cylinder wall area corresponding to the intake section is provided with a first group of heat dissipation fins, and the fin coverage area accounts for 60%-80% of the surface area of ​​the area; the cylinder wall area corresponding to the compression section is not provided with heat dissipation fins or the fin coverage area is ≤10%; the cylinder wall area corresponding to the expansion stroke is provided with a second group of heat dissipation fins, and the coverage area accounts for 50%-70%; the fin coverage area of ​​the cylinder wall area corresponding to the exhaust stage is ≤20%.

[0019] Another objective of this invention is to provide an intelligent cooling method for a vane rotor internal combustion engine, based on the aforementioned cooling system for the vane rotor internal combustion engine, specifically including the following steps: (a) The temperature signals of stator 1 and engine end cover 2 are collected in real time by temperature sensors; (b) The intelligent temperature control unit 3 dynamically adjusts the flow rate of coolant in the cooling channel 102 according to the temperature signal, and determines whether to start or stop the pump-fan integrated cooler 201 based on the real-time temperature of the end cover 2. (c) When the monitored temperature is below the high load threshold, the basic cooling mode is activated: the heat dissipation unit operates at a fixed power and relies on the natural convection of the heat dissipation fins for heat dissipation; (d) When the monitored temperature exceeds the high load threshold, activate the enhanced cooling mode: (d1) The fan speed of the pump-fan integrated cooler 201 is dynamically adjusted by the PWM signal, and the speed has a piecewise linear relationship with the end cover temperature; (d2) When the stator temperature exceeds 180℃, the coolant flow rate is increased to an over-rated level using a PID algorithm; (d3) If the temperature rise rate is detected to be >10℃ / min or the temperature continues to exceed the limit, the power reduction protection or emergency shutdown will be triggered.

[0020] Compared with the prior art, the beneficial effects of the present invention are: Compared to traditional solutions, the cooling system of this invention achieves a significant improvement in thermal management efficiency through the synergistic effect of fixed heat dissipation units and forced heat dissipation units. The fixed heat dissipation units reduce the engine's base temperature by 40-60°C, while the liquid cooling channels achieve a local temperature drop of 80°C-120°C in high heat load areas. The gradient fin design is dynamically optimized in combination with the high-altitude rare-oxygen environment. In the intake section, the fins enhance the function of the intercooler, reducing the pre-compression intake temperature. The compression section adopts an adiabatic design to raise the final compression temperature to near the ideal operating temperature. The expansion section is equipped with ultra-high-density fins to reduce the cavity wall temperature, and the exhaust section has low-resistance fins to maintain the exhaust gas temperature. Structurally, the spiral flow channel design reduces the cooling pressure drop and distributes it more evenly. The intelligent temperature control module dynamically adjusts the flow rate based on the stator temperature sensor signal, which is more energy-efficient than the constant flow mode. Attached Figure Description

[0021] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of the overall structure of the cooling system.

[0023] Figure 2 This is a diagram showing the distribution of the stator heat dissipation fins.

[0024] Figure 3 This is a cross-sectional view of the stator cooling water channel.

[0025] Figure 4 This is a block diagram of the intelligent temperature control system.

[0026] Among them, 1. stator; 2. engine end cover; 3. intelligent temperature control unit; 101. heat dissipation fins; 102. cooling channel; 201. pump-fan integrated cooler; 202. end cover heat dissipation fins. Detailed Implementation

[0027] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, and not all of the structures.

[0028] It should be noted that similar reference numerals and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. Furthermore, in the description of this invention, terms such as "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0029] Research has revealed two main challenges for traditional vane rotor engines in high-altitude or aviation applications: First, the low-oxygen environment leads to increased intake pre-compression temperatures, requiring an additional intercooler and increasing weight; second, uneven heat load distribution on the stator's curved surface causes localized overheating in the expansion section, resulting in material deformation. Existing single-mode cooling systems cannot simultaneously address both gradient heat loads and lightweight requirements. Therefore, this invention designs a four-stroke vane rotor internal combustion engine suitable for operation in high-altitude low-oxygen environments, specifically a synergistic cooling system integrating fixed and forced heat dissipation.

[0030] During the operation of a four-stroke vane rotor internal combustion engine, the stator and rotor are arranged concentrically. Driven by centrifugal force, the vanes extend radially from the vane grooves of the rotor, and their end faces dynamically conform to the continuous guideable curved surface of the stator inner ring, forming a closed sealing zone. Within this sealing zone, the following thermodynamic cycles are sequentially executed: During the intake stroke, the combustible mixture enters the gradually increasing sealed chamber through the intake port; during the compression stroke, the chamber volume decreases, causing the pressure and temperature of the mixture to rise sharply. During the combustion expansion stroke, the ignition device ignites the air-fuel mixture, and the high-temperature combustion gas pushes the vane to do work; during the exhaust stroke, the exhaust gas is discharged from the chamber through the exhaust port. The main heat generation mechanism during operation is: Combustion heat conduction: The combustion gas with extremely high peak temperature in the combustion chamber conducts heat to the inner ring curved surface of the stator and the end caps on both sides. Friction generates heat, and the relative sliding between the end face of the slider and the curved surface of the stator produces localized frictional heat.

[0031] The overall structure of the cooling system of the vane rotor internal combustion engine of the present invention is as follows: Figure 1 As shown, it is mainly assembled from an engine end cover 2 and an engine block. The engine end cover 2 includes a rear end cover and a front end cover. The rear end cover and the front end cover are respectively located on both sides of the engine block.

[0032] Both the rear and front covers are equipped with pump-fan integrated coolers 201, which are circumferentially symmetrically distributed and embedded within the end covers. Specifically, the pump-fan integrated coolers 201 are circumferentially symmetrically embedded in the annular mounting grooves of the rear and front covers, with each set of end covers equipped with two pump-fan integrated coolers (which are commonly used existing equipment, and their structure will not be described in detail), and their rated speed is infinitely adjustable from 0 to 8000 rpm. The engine block includes a stator 1, a rotor, and vanes in the rotor slots.

[0033] The stator 1 has a cooling channel 102 embedded in the thermal arc region, which corresponds to the expansion stroke contact arc segment in the stator profile. Specifically, the cooling channel 102 is provided in the inner wall interlayer of the stator 1, such as... Figure 3 As shown, the cooling channel 102 is located in the thermal arc zone corresponding to the stator profile, and the thermal arc zone of the stator 1 is arc-shaped. The cooling channel 102 is a circumferential serpentine spiral channel machined inside the stator wall, with a circular cross-section, and the distance between the channel and the inner wall surface of the stator 1 is ≤5mm. The cross-sectional structure of the cooling channel is shown below. Figure 3 As shown, the flow channel is embedded inside the stator hot arc zone wall. Specifically, the flow channel has a circular cross-section with a diameter of Φ4±0.1mm to ensure low flow resistance and high heat transfer efficiency. The flow channel is 3.0±0.5mm away from the inner wall of the stator 1 to maximize heat conduction efficiency and avoid excessive thermal resistance. The spiral cooling flow channel 102 is obliquely wrapped around the inner wall of the stator, covering the 240° wrap angle of the hot arc zone.

[0034] In this invention, the coolant in the cooling channel 102 is selected from the fuel used by the engine for cooling, which reduces the additional parts required by traditional water cooling while also achieving oil preheating.

[0035] The outer wall of the stator 1 is provided with a stator heat sink assembly. The stator heat sink assembly includes multiple axially extending heat dissipation fins 101 evenly distributed circumferentially along the outer wall of the stator 1, such as... Figure 2 As shown, it covers the entire four-stroke working section area. In this invention, due to the working conditions of each stroke section, the heat dissipation fins 101 of the stator heat sink assembly adopt a differentiated distribution of heat load gradient for each stroke section, such as... Figure 2 As shown.

[0036] Specifically, the total fin area required for each stroke stage: , in, A i Indicates the first i Total fin area required for the stroke section; λ i Indicates the first i Stroke heat load correction factor; Q i Indicates the first iThe heat dissipation during the stroke was measured through thermodynamic simulation / experiment; h This represents the overall heat transfer coefficient of the fins, which is material-dependent; Δ T i Indicates the first i The logarithmic mean temperature difference between the stator wall and the environment during the stroke.

[0037] Based on the heat dissipation and operational requirements at each stroke stage, heat dissipation fins of varying areas are designed for the four stroke stages of the rotary engine. Due to the thin oxygen environment in the aircraft's operating environment, the air undergoes compression before intake, resulting in a higher temperature before the intake stroke, traditionally requiring intercooling. Therefore, the intake stage requires more heat dissipation fins; the compression stage, to ensure compression efficiency, has few or no heat dissipation fins; the expansion stroke generates significant heat due to ignition, requiring more heat dissipation fins; and the exhaust stage, where free exhaust carries away most of the heat, requires fewer heat dissipation fins. The number of heat dissipation fins is calculated based on the total fin area mentioned above. For example, in high-altitude operating environments, such as typical conditions at altitudes ≥6000m and atmospheric pressure <47kPa, the intake working fluid needs to be pre-compressed to maintain oxygen concentration, causing the initial temperature of the intake stroke to significantly increase to the range of 80-120℃, 60-90K higher than at sea level. Traditional heat dissipation distribution patterns cannot meet these requirements.

[0038] To address this, this invention implements a targeted fin gradient distribution strategy. Specifically, for the pre-compression heat load in the intake section, a large-area fin area is configured to enhance heat dissipation and control the intake temperature at 45±5℃, effectively replacing the intercooler function. The compression section employs an adiabatic optimization design, reducing the fin area ratio and limiting heat dissipation to maintain a compression termination temperature ≥450℃, ensuring lean combustion stability and reducing compression work loss. The expansion section faces a high peak heat flux density, so a large-area fin area is configured, and the cylinder wall temperature is controlled according to the heat conduction equation to prevent excessive thermal stress. The exhaust section utilizes high-speed exhaust gas for autonomous heat dissipation, employing a low-drag, small-area fin design. This approach can replace the intercooler to lower the intake section temperature, raise the compression section temperature to ≥450℃, significantly reduce the expansion section temperature, and lower the exhaust section temperature by 15K, making it suitable for high-altitude, long-endurance UAV power applications.

[0039] In addition, end cover heat dissipation fins 202 are arranged on the outer sides of both the rear end cover and the front end cover. The end cover heat dissipation fins 202 are radially distributed, covering the rotor end face projection area on the inner surface of the rear end cover and the front end cover. The fin substrate is aluminum alloy, which is integrally processed by extrusion molding and is evenly distributed circumferentially.

[0040] In this invention, the end cover heat dissipation fins 202 specifically achieve the following functions: 1. Enhanced heat conduction: The bottom of the fins is in close contact with the cast aluminum body of the end cover, which increases the surface area and rapidly dissipates the heat conducted from the rotor end face; 2. Airflow organization optimization: The radial layout matches the airflow direction of the pump-fan integrated cooler of the forced heat dissipation unit. The axial airflow generated by the fan is accelerated through the fin gap to form turbulence, improving the convective heat transfer coefficient by ≥40%. 3. Temperature field homogenization: The fin ends extend to the periphery of the end cap bolt mounting holes to eliminate local heat accumulation.

[0041] like Figure 4 As shown, the intelligent temperature control unit 3 dynamically adjusts the coolant flow rate in the cooling channel 102 based on the temperature signal collected by the temperature sensor connected to the stator 1, and determines whether to start the pump-fan integrated cooler 201 based on the real-time temperature of the engine end cover 2, triggering the start and stop of the pump-fan integrated cooler 201. Its working process is as follows.

[0042] Step 1: System startup. After the system is powered on, it begins initialization and enters the work preparation state.

[0043] Step 2: Temperature monitoring. The system monitors the core temperature in real time (such as the temperature of key components like power devices and windings), and enters different control modes based on the comparison between the temperature and the high-load threshold temperature. Specifically, if the temperature is less than the high-load threshold temperature, it enters the basic mode; if the temperature is greater than the high-load threshold temperature, it enters the enhanced mode.

[0044] Mode 1: Basic mode (temperature < high load threshold temperature), fixed heat dissipation unit operation: the heat dissipation system (such as radiator, basic fan) operates at a preset fixed power; fin natural convection: heat is dissipated through the heat dissipation fins by natural convection, without the need for additional forced heat dissipation.

[0045] Mode 2: Enhanced Mode (Temperature > High Load Threshold Temperature). Upon entering Enhanced Mode, the system first performs forced cooling activation, and then controls the system via two paths: Path A: Safety monitoring determines the temperature change trend. If the temperature rise rate is >10℃ / min (rapid temperature rise), power reduction protection is triggered to reduce the system output power to reduce heat generation. If the temperature continues to exceed the safety threshold for a long time, an emergency shutdown is performed to cut off the system power supply to avoid overheating damage.

[0046] Path B: Fan PWM control (pulse width modulation) based on end cap temperature (key temperature measurement point of the heat dissipation system).

[0047] The fan speed of the pump-fan integrated cooler is adjusted via a PWM signal. If the end cover temperature is <160℃, the fan maintains a base speed of 4000rpm. If 160℃ ≤ end cover temperature ≤ 180℃, the fan speed increases linearly with temperature, accelerating from 4000rpm to 8000rpm. If the end cover temperature is >180℃, the fan speed is maintained at 100% full speed for maximum airflow cooling.

[0048] The enhanced mode is triggered when the system uses liquid cooling, and synchronous flow rate PID adjustment is performed in enhanced mode. If the stator temperature is ≤ 180℃: the flow rate is maintained at 100% of the rated flow rate; if 180℃ < stator temperature ≤ 200℃: the flow rate is increased to 120% through the PID algorithm, exceeding the rated flow rate to enhance heat dissipation; if the stator temperature > 200℃, it jumps to path A (safety monitoring) and performs power reduction protection or emergency shutdown.

[0049] In this invention, a forced cooling unit is formed by a cooling channel 102 located inside the stator 1 and a pump-fan integrated cooler 201 embedded in the engine end cover 2. The forced cooling unit can operate independently or in combination. A fixed cooling unit is formed by the stator heat sink assembly and the end cover heat sink fins 202, integrated into the outer wall of the stator 1 and the surface of the engine end cover 2. The fixed cooling unit and the forced cooling unit form a collaborative cooling architecture, working together. Thermal management of the stator 1, rotor ends, and sliding vane friction areas is achieved through monitoring units for different friction / heat generation areas and corresponding cooling system operating logic.

[0050] The cooling system of the vane rotor internal combustion engine of this invention is further equipped with an intelligent temperature control unit 3, which is used to detect the real-time temperature and determine the cooperative working mode. The intelligent temperature control unit 3 dynamically adjusts the coolant flow rate based on the signal from the temperature sensor connected to the stator 1, and dynamically adjusts the opening of the solenoid valve through PID control to achieve dynamic adjustment of the coolant flow rate, which is more energy-efficient than the constant flow mode. It also determines whether to activate the pump-fan integrated cooler 201 based on the real-time temperature of the end cap, achieving enhanced heat dissipation in high-heat areas. The temperature sensor signal from the intelligent temperature control unit 3 can trigger the start and stop of the pump-fan integrated cooler 201; it starts when T ≥ the threshold temperature (highest temperature) and shuts off when T ≤ the threshold temperature (lowest temperature).

[0051] Research has found that due to its unique structure, the rotary engine has a large contact area between the rotor and the cylinder block during operation, resulting in concentrated frictional heat generation. Fixed cooling units alone cannot quickly dissipate heat from high-temperature areas, easily leading to localized overheating, deformation, or seal failure. Forced cooling units, such as water cooling or fan-driven forced airflow through active circulation of cooling media or enhanced airflow, specifically enhance the heat dissipation efficiency of high-heat areas, ensuring uniform temperature distribution. Especially under high-speed, high-load conditions, forced cooling can rapidly reduce the temperature of critical components, preventing power loss or accelerated wear caused by thermal decay, and ensuring stable engine operation. Together, these two methods compensate for the inherent cooling disadvantages of the rotary engine, extending its lifespan and maintaining performance.

[0052] Furthermore, the cooling system designed in this invention is equipped with an intelligent temperature control unit to coordinate the control of fixed heat dissipation and forced heat dissipation. In terms of coordinated control, during engine start-up and under low load conditions, the forced heat dissipation unit does not need to be activated; the passive cooling of the fixed heat dissipation unit is sufficient to meet the cooling requirements. Under high load conditions (such as the expansion phase), fixed heat dissipation alone cannot meet the cooling needs; when the temperature reaches the upper limit of the threshold, the temperature control system identifies the temperature and activates the corresponding forced heat dissipation unit. The intelligent temperature control system achieves dynamic optimization control of the cooling system through multi-sensor collaborative decision-making. Thermocouples integrated in the stator thermal arc zone monitor the wall temperature in real time, and end-cover temperature sensors detect the temperature rise in the bearing area. When any temperature measurement point exceeds the threshold, the control module immediately initiates the following response: 1. Flow regulation, proportional valve based on ΔT=T 实测 -T 设定 The coolant flow rate is dynamically adjusted, and the flow rate is increased to 12L / min (+50%) when the expansion section overheats. 2. Fan linkage: The end cover fan speed is PWM modulated (4000-8000rpm), and the airflow speed increases linearly with the end cover temperature; 3. Safety redundancy: If the temperature continues to rise, power reduction protection will be triggered. During steady-state operation, the system automatically learns the heat load cycle pattern and pre-adjusts the cooling parameters 50ms in advance to keep the stator temperature fluctuation within ±5℃.

[0053] The core innovation of this invention lies in proposing a dual-modal collaborative thermal management system that integrates gradient passive heat dissipation and intelligent active cooling. Through a four-stroke differentiated fin layout, namely high density in the intake / expansion section and low density in the compression / exhaust section, adaptive heat load distribution is achieved. Combined with the forced convection of the stator near-wall spiral liquid cooling channel and the end cover fan, and employing a dynamic flow-speed coupling control method based on real-time temperature feedback, the peak temperature in the high heat flux density region is reduced while ensuring the temperature difference at the rotor end face, thus reducing the total energy consumption of the system. This successfully solves the contradiction between insufficient heat dissipation efficiency and excessive energy consumption of traditional methods in high-altitude, low-oxygen environments.

[0054] In summary, this invention provides a cooling system for a four-stroke vane rotor internal combustion engine. Through the synergistic effect of a fixed cooling unit and a forced cooling unit, it achieves efficient thermal management in the engine's high-heat-load region. The fixed cooling unit employs gradient-designed cooling fins and end-cap fins, optimized for the cooling requirements of different stroke segments. The forced cooling unit enhances the heat dissipation capacity of key components through internal stator cooling channels and end-cap fans. Combined with the dynamic adjustment of an intelligent temperature control module, this cooling system effectively solves the heat dissipation problem of vane rotor internal combustion engines under high-temperature and high-friction conditions, while also considering the requirements for lightweight design and energy efficiency optimization. It is particularly suitable for aerospace power applications in high-altitude, low-oxygen environments, significantly improving engine reliability and performance stability.

[0055] The above description is merely a preferred embodiment of the present invention. Any simple modifications, equivalent changes, and alterations made by those skilled in the art to the above embodiments without departing from the scope of the present invention and based on the technical essence of the present invention shall still fall within the scope of the present invention.

Claims

1. A cooling system for a vane rotor internal combustion engine, characterized in that: Includes forced cooling units and fixed cooling units; The forced cooling unit consists of a cooling channel (102) located inside the stator (1) of the engine body and a pump-fan integrated cooler (201) embedded in the engine end cover (2); the cooling channel (102) is located in the arc-shaped thermal arc area corresponding to the stator profile, and coolant is provided in the cooling channel (102); The fixed heat dissipation unit consists of a stator heat dissipation fin group and an end cover heat dissipation fin (202); the stator heat dissipation fin group includes multiple axially extending heat dissipation fins (101) evenly distributed along the outer wall of the stator (1), and heat dissipation fins (101) of different areas and quantities are set in the four stroke segments of the rotor engine; the end cover heat dissipation fins 202 are evenly arranged on the outer side of the rear end cover and the front end cover. It also includes an intelligent temperature control unit (3), which is communicatively connected to a temperature sensor located on the stator (1) and a pump-fan integrated cooler (201) located on the engine end cover (2); the intelligent temperature control unit (3) is configured to: control the opening of a flow regulating valve located on the cooling channel (102) based on the signal from the temperature sensor; and control the operation of the pump-fan integrated cooler (201) based on the real-time temperature of the engine end cover (2).

2. The cooling system for a sliding vane rotor internal combustion engine according to claim 1, characterized in that: The cooling channel (102) is a circumferential serpentine spiral channel machined inside the stator 1 wall. The channel cross-section is circular, and the distance between the channel and the inner wall surface of the stator (1) is ≤5mm.

3. The cooling system for a sliding vane rotor internal combustion engine according to claim 2, characterized in that: The distance between the flow channel and the inner wall of the stator (1) is 3.0±0.5mm. The spiral cooling flow channel (102) is obliquely wrapped around the inner wall of the stator, covering the 240° wrap angle of the hot arc area.

4. The cooling system for a sliding vane rotor internal combustion engine according to claim 1, characterized in that: The engine end cover (2) includes a rear end cover and a front end cover respectively located on both sides of the engine body. Both the rear end cover and the front end cover are equipped with a pump-fan integrated cooler (201). The pump-fan integrated cooler (201) is circumferentially embedded in the annular mounting groove of the rear end cover and the front end cover. Each set of end covers is equipped with (2) fans with a rated speed that is steplessly adjustable from 0 to 8000 rpm.

5. The cooling system for a sliding vane rotor internal combustion engine according to claim 1, characterized in that: The coolant in the cooling channel (102) is selected from the fuel used by the engine.

6. The cooling system for a sliding vane rotor internal combustion engine according to claim 1, characterized in that: The heat dissipation fins (101) adopt a differentiated heat load gradient distribution for the four-stroke working section, and the total fin area required for each stroke section is: , in, A i Indicates the first i Total fin area required for the stroke section; λ i Indicates the first i Stroke heat load correction factor; Q i Indicates the first i The heat dissipation during the stroke was measured through thermodynamic simulation / experiment; h This represents the overall heat transfer coefficient of the fins, which is material-dependent; Δ T i Indicates the first i The logarithmic mean temperature difference between the stator wall and the environment during the stroke.

7. The cooling system for a sliding vane rotor internal combustion engine according to claim 1, characterized in that: The end cover heat dissipation fins (202) are radially distributed, covering the rotor end face projection area on the inner surface of the rear end cover and the front end cover. The base material of the end cover heat dissipation fins (202) is aluminum alloy, which is integrally processed by extrusion molding and is evenly distributed in the circumference.

8. The cooling system for a sliding vane rotor internal combustion engine according to claim 1, characterized in that: When the temperature sensor signal of the intelligent temperature control unit (3) can trigger the start and stop of the pump-fan integrated cooler (201), the unit starts when T ≥ the highest temperature of the threshold period and shuts down when T ≤ the lowest temperature of the threshold period.

9. The cooling system for a sliding vane rotor internal combustion engine according to claim 1, characterized in that: The cylinder wall area corresponding to the intake section is provided with a first group of heat dissipation fins, and the fins cover 60%-80% of the surface area of ​​this area; The cylinder wall area corresponding to the compression section has no heat dissipation fins or the fin coverage area is ≤10%; A second group of heat dissipation fins is provided in the cylinder wall area corresponding to the expansion stroke, covering an area of ​​50%-70%; The fin coverage area of ​​the cylinder wall region during the exhaust phase is ≤20%.

10. A smart cooling method for a vane rotor internal combustion engine, characterized in that, The cooling system based on the sliding vane rotor internal combustion engine of claim 1 specifically includes the following steps: (a) The temperature signals of the stator (1) and the engine end cover (2) are collected in real time by temperature sensors; (b) The intelligent temperature control unit (3) dynamically adjusts the flow rate of coolant in the cooling channel (102) according to the temperature signal, and determines whether to start or stop the pump-fan integrated cooler (201) based on the real-time temperature of the end cap (2). (c) When the monitored temperature is below the high load threshold, the basic cooling mode is activated: the heat dissipation unit operates at a fixed power and relies on the natural convection of the heat dissipation fins for heat dissipation; (d) When the monitored temperature exceeds the high load threshold, activate the enhanced cooling mode: (d1) The fan speed of the pump-fan integrated cooler (201) is dynamically adjusted by the PWM signal, and the speed has a piecewise linear relationship with the end cover temperature; (d2) When the stator temperature exceeds 180℃, the coolant flow rate is increased to an over-rated level using a PID algorithm; (d3) If the temperature rise rate is detected to be >10℃ / min or the temperature continues to exceed the limit, the power reduction protection or emergency shutdown will be triggered.

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