CN110986696B - Active heat dissipation system of electric steering engine and heat dissipation method thereof - Google Patents
Active heat dissipation system of electric steering engine and heat dissipation method thereof Download PDFInfo
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- CN110986696B CN110986696B CN201911082437.3A CN201911082437A CN110986696B CN 110986696 B CN110986696 B CN 110986696B CN 201911082437 A CN201911082437 A CN 201911082437A CN 110986696 B CN110986696 B CN 110986696B
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- 230000017525 heat dissipation Effects 0.000 title claims abstract description 87
- 238000000034 method Methods 0.000 title claims abstract description 19
- 239000002360 explosive Substances 0.000 claims abstract description 26
- 230000000977 initiatory effect Effects 0.000 claims abstract description 26
- 239000007921 spray Substances 0.000 claims abstract description 17
- 239000007789 gas Substances 0.000 claims description 52
- 239000000112 cooling gas Substances 0.000 claims description 22
- 230000004913 activation Effects 0.000 claims description 5
- 230000000694 effects Effects 0.000 claims description 5
- 238000007789 sealing Methods 0.000 claims description 5
- 230000006835 compression Effects 0.000 claims description 3
- 238000007906 compression Methods 0.000 claims description 3
- 239000002826 coolant Substances 0.000 description 3
- 238000001816 cooling Methods 0.000 description 3
- 238000010586 diagram Methods 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- 230000007423 decrease Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000009413 insulation Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
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Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F42—AMMUNITION; BLASTING
- F42B—EXPLOSIVE CHARGES, e.g. FOR BLASTING, FIREWORKS, AMMUNITION
- F42B15/00—Self-propelled projectiles or missiles, e.g. rockets; Guided missiles
- F42B15/34—Protection against overheating or radiation, e.g. heat shields; Additional cooling arrangements
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- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Aviation & Aerospace Engineering (AREA)
- Combustion & Propulsion (AREA)
- General Engineering & Computer Science (AREA)
- Power Steering Mechanism (AREA)
- Steering Control In Accordance With Driving Conditions (AREA)
Abstract
The invention relates to an active heat dissipation system of an electric steering engine and a heat dissipation method thereof, wherein the active heat dissipation system of the electric steering engine comprises a controller, a compressed gas cylinder, a sealed initiating explosive device, a servo valve, an air guide spray pipe and a temperature sensor; the temperature sensor is arranged at the heat dissipation part of the electric steering engine and transmits the temperature of the heat dissipation part measured in real time to the controller; the compressed gas cylinder is connected with the servo valve through the sealed initiating explosive device; the air guide spray pipe is connected with the servo valve; the sealed initiating explosive device and the servo valve are connected with the controller. According to the active heat dissipation system and the heat dissipation method of the electric steering engine, heat dissipation is accurately performed on easily-heated devices and weak links of the electric steering engine, and the steering engine component is guaranteed to be within a normal working temperature range in the flight time, so that the working reliability of the steering engine is improved.
Description
Technical Field
The invention relates to the technical field of electric steering engines, in particular to an active heat dissipation system of an electric steering engine and a heat dissipation method of the active heat dissipation system.
Background
The hypersonic aircraft has the characteristics of wide flight airspace, long flight time, high flight speed and the like, and simultaneously causes the thermal environment of the electric steering engine to be extremely harsh, firstly, the heat is transferred into a rudder cabin through the surface of the cabin body under the influence of continuous pneumatic heating outside the hypersonic aircraft during the hypersonic cruise of the aircraft; secondly, a large amount of heat is dissipated to a rudder cabin space after the engine burns; finally, the electric steering engine continuously works under high dynamic and heavy load, and the motor and the power module can generate a large amount of heat. If the heat cannot be diffused outwards in an effective way, the reliability and safety of the steering engine can be seriously influenced, and even serious consequences such as failure of the electric steering engine can be caused.
At present, the mode adopted by the electric steering engine in short voyage is mainly heat insulation and high-temperature resistant materials and devices, so that external pneumatic heating is isolated, and meanwhile, the heat resistance of the devices of the electric steering engine is improved. For long endurance, high speed aircraft, these measures are difficult to meet mission requirements. The traditional temperature control convection heat dissipation system has a good heat dissipation effect, but is large in size and occupies too much volume and weight.
Disclosure of Invention
The invention aims to provide an active heat dissipation system of an electric steering engine and a heat dissipation method thereof, which are used for accurately dissipating heat of easily-heated devices and weak links of the electric steering engine and ensuring that rudder system components are within a normal working temperature range in flight time, so that the working reliability of the steering engine is improved.
In order to achieve the aim, the invention provides an active heat dissipation system of an electric steering engine, which comprises a controller, a compressed air cylinder, a sealed initiating explosive device, a servo valve, an air guide spray pipe and a temperature sensor, wherein the controller is connected with the compressed air cylinder; the temperature sensor is arranged at the heat dissipation part of the electric steering engine and transmits the temperature of the heat dissipation part measured in real time to the controller; the compressed gas cylinder is connected with the servo valve through the sealed initiating explosive device; the air guide spray pipe is connected with the servo valve; the sealed initiating explosive device and the servo valve are connected with the controller.
According to the active heat dissipation system of the electric steering engine, when the active heat dissipation system of the electric steering engine is in an inactivated state, the compressed gas cylinder is sealed by the sealing initiating explosive device.
In the active heat dissipation system of the electric steering engine, the controller sends an activation signal to the sealed initiating explosive device to enable the compressed gas cylinder to be communicated with the servo valve; the controller sends a flow control signal to the servo valve to control the flow of the cooling gas; and cooling gas output by the compressed gas cylinder passes through the servo valve and is sprayed out from a gas nozzle of the gas guide spray pipe.
The active heat dissipation system of the electric steering engine further comprises a one-way stop safety valve, wherein the one-way stop safety valve is mounted on the cabin wall of the electric steering engine cabin and discharges the air in the cabin outside the cabin.
The active heat dissipation system of the electric steering engine is characterized in that normal-temperature high-pressure gas is stored in the gas cylinder compression.
The active heat dissipation system of the electric steering engine comprises a power module and a motor, wherein the power module and the motor are arranged together.
The invention provides another technical scheme which is an active heat dissipation method of an electric steering engine, and the active heat dissipation system of the electric steering engine is adopted, and the active heat dissipation method comprises the following steps:
when the gas cylinder is in a non-activated state, the sealing initiating explosive device seals the compressed gas cylinder;
when heat dissipation is needed, the controller sends an activation signal to the sealed initiating explosive device to activate the sealed initiating explosive device, and the compressed gas cylinder is communicated with the servo valve; the compressed gas cylinder releases cooling gas, and the cooling gas is sprayed out from the gas guide spray pipe through the servo valve; the temperature sensor sends the measured temperature to the controller in real time, and the controller sends a flow control signal to the servo valve according to the temperature to control the duty ratio of the servo valve, so that the flow of the cooling gas is adjusted.
The active heat dissipation method of the electric steering engine comprises the following steps that the heat dissipation part of the electric steering engine comprises a power module and a motor, and the duty ratio of a servo valve is as follows:
wherein u is the duty cycle of the servo valve; t is l ,T 2 Respectively the temperature values of the motor and the power module; k is a radical of 1 ,k 2 Is a parameter; t is l0 ,T 20 Respectively setting the temperature values when the motor and the power module start to radiate heat;
feed forward to compensate for temperature control hysteresis effects.
According to the active heat dissipation method of the electric steering engine, the power module and the motor are arranged together.
The active heat dissipation method of the electric steering engine further comprises the step that air in the cabin of the electric steering engine is discharged to the outside of the cabin through a one-way stop safety valve on the cabin wall.
Compared with the prior art, the invention has the advantages that:
(1) By adopting an active heat dissipation technology, heat is dissipated to easily-heated devices and weak links of the electric steering engine accurately, so that the working reliability of the electric steering engine is ensured;
(2) Compared with the original rudder system, the active heat dissipation system only needs to be added with a compressed gas cylinder, a servo valve and an air guide spray pipe, the weight and the volume are not greatly increased, and the active heat dissipation system is suitable for occasions with high power-to-mass ratio requirements;
(3) The flow of the gas is adjusted through the servo valve, the flow is high when the temperature difference is large, the flow is low when the temperature difference is small, and the working efficiency of the heat dissipation system is effectively improved;
(4) The cooling medium is a high-pressure gas source, and the lower the temperature of the cooling gas is, the higher the heat dissipation efficiency is as the gas of the gas cylinder does work.
Drawings
The active heat dissipation system of the electric steering engine and the heat dissipation method thereof are provided by the following embodiments and the attached drawings.
Fig. 1 is a schematic diagram of an active heat dissipation system of an electric steering engine according to a preferred embodiment of the present invention.
Fig. 2 is a schematic view illustrating active heat dissipation control of an active heat dissipation system of an electric steering engine according to a preferred embodiment of the present invention.
Detailed Description
The active heat dissipation system of the electric steering engine and the heat dissipation method thereof will be further described in detail with reference to fig. 1 to 2.
The active heat dissipation system of the electric steering engine utilizes air cooling for active heat dissipation, and directly provides a heat exchange medium for the heat concentration part of the electric steering engine for forced convection heat dissipation.
Fig. 1 is a schematic diagram of an active heat dissipation system of an electric steering engine according to a preferred embodiment of the present invention.
Referring to fig. 1, the active heat dissipation system of the electric steering engine of the present embodiment includes: the device comprises a controller, a compressed gas cylinder, a sealed initiating explosive device, a servo valve, an air guide spray pipe and a temperature sensor;
the temperature sensor is arranged at a heat dissipation part of the electric steering engine and used for measuring the temperature of the heat dissipation part in real time;
high-pressure gas is stored in the gas cylinder compression;
the compressed gas cylinder is connected with the servo valve through the sealed initiating explosive device;
the air guide spray pipe is connected with the servo valve;
the sealed initiating explosive device, the servo valve and the temperature sensor are all connected with the controller.
In the flight process of the hypersonic aircraft, a heat concentration part and a heated weak link in the electric steering engine can be regarded as a heat dissipation part of the electric steering engine, such as a motor and a power module, and a potentiometer can also be regarded as a heat dissipation part of the electric steering engine; temperature sensors can be respectively arranged at the radiating parts of the electric steering engine (for example, the temperature sensors are respectively arranged on the motor and the power module), and the temperature sensors measure the temperature of the radiating parts in real time and send the measurement result to the controller in real time.
In the present embodiment, the gas cylinder is compressed to store therein a normal-temperature high-pressure gas to be used as a cooling medium. The servo valve is an electric servo valve.
When heat dissipation is needed, the controller sends an activation signal to the sealed initiating explosive device to enable the compressed gas cylinder to be communicated with the servo valve, the compressed gas cylinder outputs cooling gas (cooling medium), and the cooling gas passes through the servo valve and the gas guide spray pipe and is sprayed out from a gas nozzle of the gas guide spray pipe; the controller sends a flow control signal to the servo valve to control the flow of the cooling gas; cooling gas sprayed out of a gas nozzle of the gas guide spray pipe directly takes away heat from a heat concentration part and a heated weak link through forced convection heat exchange; finally, the air in the electric rudder cabin is exhausted out of the cabin through a one-way stop safety valve on the cabin wall, as shown in figure 1.
Fig. 2 is a schematic view illustrating active heat dissipation control of an active heat dissipation system of an electric steering engine according to a preferred embodiment of the present invention.
Referring to fig. 2, when the active heat dissipation system of the electric steering engine is in an inactive state, the sealing initiating explosive device seals the compressed gas cylinder; when the active heat dissipation system needs to be activated, the controller sends an activation signal to the sealed initiating explosive device to activate the sealed initiating explosive device, the compressed gas cylinder is communicated with the servo valve, and the controller starts to perform servo control on the flow of the cooling gas;
after the sealed initiating explosive device is activated, the compressed gas cylinder releases cooling gas, and the cooling gas is controlled by the flow of the servo valve and is sprayed out from a gas nozzle of the gas guide spray pipe; the sprayed cooling gas directly takes away heat from the heat concentration part and the heated weak link; the air in the electric rudder cabin is discharged out of the cabin through a one-way stop safety valve on the cabin wall;
the temperature sensor measures the temperature of the heat concentration part and the temperature of the heated weak link in real time and sends the measurement result to the controller in real time; the controller sends a flow control signal to the servo valve according to the temperature of the heat concentration part and the temperature of the heated weak link, controls the duty ratio of the servo valve and adjusts the flow of the cooling gas.
The heat concentration part and the weak link of being heated take a motor and a power module as examples, and the duty ratio of the servo valve is as follows:
wherein u is the duty cycle of the servo valve; t is l ,T 2 Respectively the temperature values of the motor and the power module; k is a radical of formula 1 ,k 2 Is a parameter; t is l0 ,T 20 Respectively setting temperature values (namely initial temperature values) when the motor and the power module start to radiate heat;
feed forward to compensate for temperature control hysteresis effects.
Taking the current control period as a time starting point, and setting the corresponding motor temperature to be T within the time of tau =0, -T 10 ,t 11 ,...t 1m Corresponding to a power module temperature of t 20 ,t 21 ,...t 2m Corresponding to motor current of I 0 ,I 1 ,...,I m . Since the temperature has hysteresis effect, the least square theorem is used for controlling the motor and the motor in the time of m control periodsFitting a power module temperature curve:
wherein
Wherein i =1,2. Predicting the temperature of the motor and the power module in the next control period as follows:
calculating the power of the steering engine in the time of m control cycles:
the gas flow feedforward control quantity can be calculated by combining the temperature of the power module, the temperature of the motor and the power of the steering engine
Wherein k is 3 ,k 4 ,k 5 ,k 6 Are design parameters.
In the embodiment, in order to improve the efficiency of active heat dissipation, the power module and the motor are arranged together, cooling gas is directly sprayed to the power module and the motor through the air guide spray pipe, heat is taken away through forced convection heat exchange of the high-speed cooling gas, and the gas in the cabin of the electric rudder is discharged to the outside of the cabin through the one-way stop safety valve on the cabin wall. Comparing the heat dissipation efficiency of active heat dissipation and natural cooling, according to the Newton cooling formula, the heat dissipation capacity of the motor and the power module is as follows:
wherein,
for heat dissipation flow, h i To the heat transfer coefficient, A i Is the heat dissipation area, t i For temperature values, subscript i =0,1,2.0 denotes cooling gas, 1 denotes a motor, and 2 denotes a power module.
The forced convection heat transfer coefficient of the gas is about 4 times of the natural convection heat transfer coefficient, namely h i The improvement can be improved by about 4 times; meanwhile, the forced convection can take away the heated gas and keep the cooling gas directly delivered to the surface of the heat source, so that t is the active heat dissipation 0 Basically remains unchanged and the heat dissipation flow is constant
Is substantially unchanged; the natural heat dissipation can only be realized through heat conduction, and the temperature t of the gas in the cabin 0 Gradually increase and dissipate heat flow
Gradually decreases. Therefore, the active heat dissipation is improved by more than 4 times than the natural heat dissipation.
Through the volume that changes the gas cylinder, satisfy the heat dissipation demand of different time of flight, reduced overheated risk, improved the fail safe nature of rudder system when the aircraft cruises.
Claims (4)
1. An active heat dissipation method of an electric steering engine is characterized in that an active heat dissipation system of the electric steering engine is adopted, and the active heat dissipation system comprises a controller, a compressed gas cylinder, a sealed initiating explosive device, a servo valve, an air guide spray pipe and a temperature sensor;
the temperature sensor is arranged at the heat dissipation part of the electric steering engine and transmits the temperature of the heat dissipation part measured in real time to the controller;
the compressed gas cylinder is connected with the servo valve through the sealed initiating explosive device;
the air guide spray pipe is connected with the servo valve;
the sealed initiating explosive device and the servo valve are both connected with the controller, the active heat dissipation system of the electric steering engine also comprises a one-way stop safety valve which is arranged on the bulkhead of the electric rudder cabin and discharges the air in the cabin out of the cabin,
the active heat dissipation method comprises the following steps:
when the gas cylinder is in a non-activated state, the sealing initiating explosive device seals the compressed gas cylinder;
when heat dissipation is needed, the controller sends an activation signal to the sealed initiating explosive device to activate the sealed initiating explosive device, and the compressed gas cylinder is communicated with the servo valve; the compressed gas cylinder releases cooling gas, and the cooling gas is sprayed out from the gas guide spray pipe through the servo valve; the temperature sensor sends the measured temperature to the controller in real time, the controller sends a flow control signal to the servo valve according to the temperature to control the duty ratio of the servo valve so as to adjust the flow of the cooling gas,
if electric steering engine's heat dissipation part position includes power module and motor, the servo valve duty cycle is:
wherein u is the duty cycle of the servo valve; t is l ,T 2 Respectively the temperature values of the motor and the power module; k is a radical of 1 ,k 2 Is a proportional gain parameter; t is l0 ,T 20 Respectively setting the temperature values when the motor and the power module start to radiate heat;
feed forward to compensate for temperature control hysteresis effects.
2. The active heat dissipation method of the electric steering engine according to claim 1, wherein when the active heat dissipation system of the electric steering engine is in an inactive state, the sealing initiating explosive device seals the compressed gas cylinder.
3. The active heat dissipation method of the electric steering engine according to claim 1, wherein normal-temperature high-pressure gas is stored in the gas cylinder compression.
4. The active heat dissipation method for electric steering engines of claim 1, wherein the power module and the motor are disposed together.
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| CN112413100B (en) * | 2020-12-01 | 2022-07-01 | 上海航天控制技术研究所 | Long-endurance high-speed aircraft rudder shaft liquid flow cooling method and structure |
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| US5131236A (en) * | 1990-05-21 | 1992-07-21 | Honeywell Inc. | Air handling system utilizing direct expansion cooling |
| US5261243A (en) * | 1992-09-28 | 1993-11-16 | Lockheed Corporation | Supplemental cooling system for avionic equipment |
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