Phase change cold storage and temperature control water tank combined laser heat management system and management method thereof

Abstract

The invention relates to the technical field of laser heat management, and provides a laser heat management system combining phase change cold storage and a temperature control water tank and a management method of the laser heat management system, which can realize a laser heat pipe under the conditions of low power consumption and small size. The variable-frequency pump is adopted to adjust the flow so as to control the temperature of the temperature control water tank, compared with a valve adjusting method, one valve is omitted, meanwhile, the variable-frequency pump is adjustable in power, and power consumption is reduced; the phase change regenerator is adopted to replace traditional liquid sensible heat cold accumulation, and the cold accumulation size is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of laser thermal management, and in particular to a laser thermal management system combining a phase change cold storage and a temperature control water tank and a management method thereof. Background Art

[0002] In recent years, with the increasing demand for high-power lasers in application fields such as manufacturing and space exploration, achieving high-power and high-performance output of all-solid-state, optical fiber and semiconductor lasers has become the research focus of scientific researchers. The electro-optical conversion efficiency of the laser is low, and 50% to 60% of the electrical energy is converted into heat energy. If the heat dissipation effect is not good, the chip temperature will rise, which will directly affect the threshold current density, output power, differential quantum efficiency and other performance of the semiconductor laser, and lead to a decrease in the life and reliability of the laser, and even damage the chip. Therefore, the heat dissipation problem has become a key factor restricting the further improvement of laser power and beam quality.

[0003] Lasers have high heat flux density and high-precision temperature control requirements. To ensure high-efficiency output, the inlet coolant temperature requirement is usually 25±1°C. The existing thermal management system is relatively large in size and weight. Summary of the invention

[0004] In view of this, the present invention provides a laser thermal management system and a management method thereof that combines a phase change cold storage and a temperature-controlled water tank, which can achieve laser thermal management with low power consumption and small volume.

[0005] To achieve the above-mentioned purpose, the present invention provides a laser thermal management system combining phase change cold storage and temperature control water tank, comprising a laser, a water tank, an electric heating wire, a first water pump, a frequency conversion pump, a phase change cold storage, a second water pump, a three-way valve, an evaporator, an expansion valve, a compressor, a condenser, a radiator and a fan; wherein the electric heating wire is used to preheat the antifreeze of the laser and the temperature control water tank; the temperature control water tank is connected to the first water pump, and a laser is arranged between the first water pump and the temperature control water tank; the frequency conversion pump is connected to the temperature control water tank, and the water flow speed and water pressure are controlled by changing the frequency; the phase change cold storage is connected to the frequency conversion pump; the evaporator is connected to the phase change cold storage; the second water pump is connected to the evaporator; the expansion valve is connected between the evaporator and the condenser; the three-way valve is connected to the cold storage, the radiator and the evaporator; the compressor is connected to the evaporator and the condenser; a fan is arranged next to the radiator; the second water pump adopts a frequency conversion pump, and the speed and flow are adjusted according to the water tank temperature to ensure the water tank temperature; the first water pump is downstream of the water tank, and the pressure of the coolant is reduced after passing through the laser and returns to the water tank.

[0006] Wherein, the electric heating wire is arranged in the temperature-controlled water tank.

[0007] Among them, the cold storage device adopts a plate-fin phase change cold storage device, the plate-fin phase change cold storage device is made of aluminum alloy material, and the cold storage device is placed vertically; the cold storage device adopts a countercurrent configuration, and the cold side and the hot side have an inlet and an outlet respectively.

[0008] Among them, the cold storage device uses solid-liquid phase change material as the cold storage medium, and the temperature of the phase change material is 5 to 20°C.

[0009] Among them, the pressure valve is turned on the upper part of the water tank, and the pressure valve ensures that the system is not over-pressurized.

[0010] The present invention also provides a management method for a laser thermal management system combining phase change cold storage and a temperature control water tank, comprising the following steps:

[0011] In the startup preparation stage, when the ambient temperature is between -40 and 24°C, the laser does not work, the first water pump works, and the system preheats the heat source and the antifreeze in the temperature-controlled water tank to 25±1°C through the electric heating wire; when the ambient temperature is between 26 and 50°C, the first water pump, the variable frequency pump, the second water pump, and the fan work, the three-way valve switches to the evaporator circuit, and the refrigeration cycle works to cool the temperature-controlled water tank to 25±1°C and the outlet temperature of the phase-change refrigerant to 16°C;

[0012] During the laser working stage, the laser generates heat. When the ambient temperature is between -40 and +5°C, the first water pump works to cool the heat source, and the coolant returns to the temperature-controlled water tank. The variable frequency pump changes speed according to the temperature of the temperature-controlled water tank to extract part of the coolant from the temperature-controlled water tank and cool it through the phase-change cold storage device, keeping the temperature of the temperature-controlled water tank at 25±1°C. At the same time, when the temperature of the cold storage device is higher than 16°C, the second water pump starts, and the coolant flows through the second water pump, the phase-change cold storage device, and the radiator, transferring the heat from the cold storage device to the radiator, and the fan rotates to take away the heat.

[0013] After the laser is turned on, it generates heat. When the ambient temperature is between 5 and +50°C, the first water pump works to cool the laser, and the coolant returns to the water tank. The variable frequency pump cools part of the coolant in the cold storage device according to the detected water tank temperature, and keeps the water tank temperature at 25±1°C. At the same time, when the temperature of the phase change cold storage device is higher than 16°C, the second water pump works to transfer the heat from the cold storage device to the evaporator, the refrigeration cycle works, and the fan rotates to take away the heat.

[0014] After the laser is turned off, when the ambient temperature is between -40 and 5°C: the first water pump works, and the coolant returns to the temperature-controlled water tank through the laser; the variable frequency pump changes speed according to the temperature of the temperature-controlled water tank to extract part of the coolant from the temperature-controlled water tank and cool it through the phase-change cold storage device, keeping the temperature of the temperature-controlled water tank at 25±1°C; the second water pump and fan continue to work, and the coolant flows through the second water pump, the phase-change cold storage device, and the radiator, transferring the heat of the phase-change cold storage device to the environment until the outlet temperature of the hot side of the phase-change cold storage device is less than 16°C;

[0015] After the laser is turned off, when the ambient temperature is between 5 and +50°C: the first water pump, the variable frequency pump, the second water pump, and the fan work, the three-way valve switches to the evaporator circuit, and the refrigeration cycle works to cool the temperature-controlled water tank to 25±1°C and the phase change refrigerant outlet temperature to 16°C.

[0016] Beneficial effects:

[0017] 1. The system of the present invention adopts a variable frequency pump to adjust the flow rate and thus control the temperature of the temperature-controlled water tank, which saves a valve compared to the valve adjustment method. At the same time, the power of the variable frequency pump is adjustable, saving power consumption; a phase change cold storage device is used instead of traditional liquid sensible heat cold storage to reduce the cold storage volume.

[0018] 2. The temperature-controlled water tank in the system of the present invention adopts a direct mixing method of cold and hot water to improve the heat exchange efficiency and save an intermediate heat exchanger.

[0019] 3. In the system of the present invention, a pressure valve is screwed on the upper part of the water tank, and the pressure valve ensures that the system is not over-pressurized.

[0020] 4. In the system of the present invention, the cold storage device adopts a plate-fin phase change cold storage device, an aluminum alloy material, and rectangular fins. The cold storage device adopts a countercurrent configuration, and the cold side and the hot side have an inlet and an outlet respectively; and the cold storage device is placed vertically to prevent the contact thermal resistance with the metal wall caused by shrinkage during the solidification process.

[0021] 5. In the system of the present invention, the cold storage device uses solid-liquid phase change material as the cold storage medium. To ensure the efficiency of the refrigeration cycle, the phase change material temperature is 5-20°C, such as pure substances such as n-tetradecane, octanoic acid, polyethylene glycol and their eutectic mixtures. The cold storage material can provide continuous cold in a short time and play a role in stabilizing the cold output.

[0022] 6. The method of the present invention is implemented based on the system of the present invention, and a variable frequency pump is used to adjust the flow rate to control the temperature of the temperature-controlled water tank. Compared with the valve adjustment method, a valve is omitted, and the power of the variable frequency pump is adjustable, which saves power consumption. A phase change cold storage device is used instead of traditional liquid sensible heat cold storage to reduce the cold storage volume. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 The schematic diagram of the system embodiment of the present invention.

[0024] Figure 2 Schematic diagram of a single-cycle structure of a cold storage device in a system embodiment of the present invention.

[0025] Figure 3 Schematic diagram of the internal fin structure of the cold storage layer in the system embodiment of the present invention.

[0026] Figure 4 Schematic diagram of the internal structure of the cold side in the system embodiment of the present invention. DETAILED DESCRIPTION

[0027] The present invention is described in detail below with reference to the accompanying drawings and embodiments.

[0028] The embodiment of the present invention provides a laser thermal management system combining phase change cold storage and temperature control water tank, such as Figure 1 As shown, it includes a laser, a temperature-controlled water tank, an electric heating wire, a first water pump, a variable frequency pump, a phase-change cold storage device, a second water pump, a three-way valve, an evaporator, an expansion valve, a compressor, a condenser, a radiator, and a fan; wherein, the second water pump adopts a variable frequency pump, and the speed and flow rate are adjusted according to the temperature of the temperature-controlled water tank to ensure that the temperature of the temperature-controlled water tank is within 25±1℃. The first water pump is downstream of the temperature-controlled water tank, and the pressure of the coolant is reduced after passing through the laser and returns to the water tank, reducing the pressure of the water tank.

[0029] The electric heating wire is used to preheat the antifreeze of the heat source (laser) and the temperature-controlled water tank. In this embodiment, the electric heating wire is set in the temperature-controlled water tank. The first water pump is the starting point in the system and is responsible for transporting water to other parts of the system to ensure the circulation of water; the temperature-controlled water tank is connected to the first water pump and is used to adjust the temperature of the water. It is a key part of controlling the temperature of the air-conditioning system; a laser is arranged between the first water pump and the temperature-controlled water tank; a variable frequency pump is connected to the temperature-controlled water tank and controls the water flow rate and water pressure by changing the frequency to adapt to different working requirements; a phase-change cold storage device is connected to the variable frequency pump and may store or release heat to help adjust the water temperature and achieve more efficient temperature control; an evaporator is connected to the phase-change cold storage device. In the refrigeration cycle, the coolant in the evaporator absorbs heat to evaporate, thereby playing a cooling role; a second water pump is connected to the evaporator; an expansion valve is connected between the evaporator and the condenser to adjust the flow of the refrigerant entering the evaporator and control the refrigeration effect; a three-way valve is connected to the cold storage device, the radiator and the evaporator. This valve can divert or merge the fluid to help adjust the direction and flow of the water flow.

[0030] The compressor connects the evaporator and the condenser. The compressor compresses the refrigerant gas, increases its pressure and temperature, and provides power for the refrigeration cycle. The condenser is connected to the compressor. During the refrigeration process, it converts the gaseous refrigerant into liquid and releases heat at the same time. The radiator is used to dissipate heat and cool the air. It is a key part of the system to cool the air. A fan is installed next to the radiator to remove heat through air flow. The entire system achieves functions such as heating, cooling, and humidity control through the coordinated work of these components. Figure 1 The working principle of the system and the functions and connections of each component are demonstrated in detail.

[0031] In the system of the present invention, the cold storage device adopts a plate-fin phase change cold storage device, made of aluminum alloy, and adopts rectangular fins. The cold storage device is placed vertically to prevent the contact thermal resistance with the metal wall caused by shrinkage during the solidification process; the cold storage device adopts a countercurrent configuration, and the cold side and the hot side have an inlet and an outlet respectively. Figure 2Schematic diagram of a single-cycle structure of a cold storage device in a system embodiment of the present invention. Figure 3 Schematic diagram of the internal fin structure of the cold storage layer in the system embodiment of the present invention. Figure 4 Schematic diagram of the internal structure of the cold side in the system embodiment of the present invention.

[0032] Furthermore, the cold storage device uses solid-liquid phase change materials as cold storage media. To ensure the efficiency of the refrigeration cycle, the temperature of the phase change material is 5-20°C, such as pure substances such as n-tetradecane, octanoic acid, polyethylene glycol and their eutectic mixtures. The cold storage material can provide continuous cooling in a short time and play a role in stabilizing the cooling output.

[0033] Furthermore, a pressure valve is screwed onto the upper portion of the water tank, and the pressure valve ensures that the system is not over-pressurized.

[0034] The present invention also provides a management method for a laser thermal management system combining variable cold storage and a temperature-controlled water tank, comprising the following steps:

[0035] In the startup preparation stage, when the ambient temperature is between -40 and 24°C, the laser does not work, the first water pump works, and the system preheats the heat source and the antifreeze in the temperature-controlled water tank to 25±1°C through the electric heating wire. When the ambient temperature is between 26 and 50°C, the first water pump, the variable frequency pump, the second water pump, and the fan work, the three-way valve switches to the evaporator circuit, and the refrigeration cycle works to cool the temperature-controlled water tank to 25±1°C and the outlet temperature of the phase-change regenerator to 16°C.

[0036] During the laser working stage, the laser generates heat. When the ambient temperature is between -40 and +5°C, the first water pump works to cool the heat source, and the coolant returns to the temperature-controlled water tank. The frequency conversion pump changes speed according to the temperature of the temperature-controlled water tank to extract part of the coolant from the temperature-controlled water tank and cool it through the phase-change cold storage device, keeping the temperature of the temperature-controlled water tank at 25±1°C. At the same time, when the temperature of the cold storage device is higher than 16°C, the second water pump starts, and the coolant flows through the second water pump, the phase-change cold storage device, and the radiator, transferring the heat from the cold storage device to the radiator, and the fan rotates to take the heat away. The fan changes speed according to the temperature of the hot side outlet of the cold storage device. The higher the temperature of the hot side outlet, the faster the speed.

[0037] After the laser is turned on, the laser generates heat. When the ambient temperature is between 5 and +50°C, the first water pump works to cool the laser, and the coolant returns to the water tank. The frequency conversion pump cools part of the coolant in the cold storage device according to the detected water tank temperature, and keeps the water tank temperature at 25±1°C. At the same time, when the temperature of the phase change cold storage device is higher than 16°C, the second water pump works to transfer the heat from the cold storage device to the evaporator, the refrigeration cycle works, and the fan rotates to take away the heat. The fan works at a variable speed according to the temperature of the hot side outlet of the cold storage device. The higher the temperature of the hot side outlet, the faster the speed.

[0038] After the laser is turned off, when the ambient temperature is between -40 and 5°C: the first water pump works, and the coolant returns to the temperature-controlled water tank through the laser. Due to the heat generated by the first water pump, the temperature of the temperature-controlled water tank will slowly rise. The variable frequency pump changes speed according to the temperature of the temperature-controlled water tank to extract part of the coolant from the temperature-controlled water tank and cool it through the phase-change refrigerant to keep the temperature of the temperature-controlled water tank at 25±1°C. The second water pump and fan continue to work, and the coolant flows through the second water pump, the phase-change refrigerant, and the radiator, transferring the heat of the phase-change refrigerant to the environment until the outlet temperature of the hot side of the phase-change refrigerant is less than 16°C. The fan changes speed according to the temperature of the hot side outlet of the refrigerant. The higher the temperature of the hot side outlet, the faster the speed.

[0039] After the laser is turned off, when the ambient temperature is between 5 and +50°C: the first water pump, the variable frequency pump, the second water pump, and the fan work, the three-way valve switches to the evaporator circuit, and the refrigeration cycle works to cool the temperature-controlled water tank to 25±1°C and the phase change refrigerant outlet temperature to 16°C.

[0040] In summary, the above are only preferred embodiments of the present invention and are not intended to limit the protection scope of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A laser thermal management system combining phase change cold storage and temperature control water tank, characterized in that: It includes a laser, a water tank, an electric heating wire, a first water pump, a frequency conversion pump, a phase change cold storage device, a second water pump, a three-way valve, an evaporator, an expansion valve, a compressor, a condenser, a radiator and a fan; wherein the electric heating wire is used to preheat the antifreeze of the laser and the temperature-controlled water tank; the temperature-controlled water tank is connected to the first water pump, and a laser is arranged between the first water pump and the temperature-controlled water tank; the frequency conversion pump is connected to the temperature-controlled water tank, and the water flow rate and water pressure are controlled by changing the frequency; the phase change cold storage device is connected to the frequency conversion pump; the evaporator is connected to the phase change cold storage device; the second water pump is connected to the evaporator; the expansion valve is connected between the evaporator and the condenser; the three-way valve is connected to the cold storage device, the radiator and the evaporator; the compressor is connected to the evaporator and the condenser; a fan is arranged next to the radiator; the second water pump adopts a frequency conversion pump, and the speed and flow are adjusted according to the water tank temperature to ensure the water tank temperature; the first water pump is downstream of the water tank, and the pressure of the coolant is reduced after passing through the laser and returns to the water tank.

2. The system according to claim 1, characterized in that The electric heating wire is arranged in the temperature-controlled water tank.

3. The system according to claim 2, characterized in that The cold storage device adopts a plate-fin phase change cold storage device, which is made of aluminum alloy and is placed vertically; the cold storage device adopts a countercurrent configuration, and the cold side and the hot side have an inlet and an outlet respectively.

4. The system according to claim 3, characterized in that ,The cold storage device uses solid-liquid phase change material as the cold storage medium and the ,phase change material temperature is between 5 and 20 ℃.

5. The system according to any one of claims 1 to 4, characterized in that , turn on the pressure valve on the top of the water tank. The pressure valve ensures that the system is not over-pressurized.

6. A management method for a laser thermal management system combining a phase change cold storage and a temperature control water tank as claimed in any one of claims 1 to 5, comprising the following steps: In the startup preparation stage, when the ambient temperature is between -40 and 24°C, the laser does not work, the first water pump works, and the system preheats the heat source and the antifreeze in the temperature-controlled water tank to 25±1°C through the electric heating wire; when the ambient temperature is between 26 and 50°C, the first water pump, the frequency conversion pump, the second water pump, and the fan work, the three-way valve switches to the evaporator circuit, and the refrigeration cycle works to cool the temperature-controlled water tank to 25±1°C and the outlet temperature of the phase change refrigerant to 16°C; during the laser working stage, the laser The device is heated. When the ambient temperature is between -40 and +5°C, the first water pump starts to cool the heat source, and the coolant returns to the temperature-controlled water tank. The variable frequency pump changes speed according to the temperature of the temperature-controlled water tank to extract part of the coolant from the temperature-controlled water tank and cool it through the phase-change cold storage device to keep the temperature of the temperature-controlled water tank at 25±1°C. At the same time, when the temperature of the cold storage device is higher than 16°C, the second water pump starts, and the coolant flows through the second water pump, the phase-change cold storage device, and the radiator to transfer the heat from the cold storage device to the radiator, and the fan rotates to take the heat away. After the laser is turned on, it generates heat. When the ambient temperature is between 5 and +50°C, the first water pump works to cool the laser, and the coolant returns to the water tank. The variable frequency pump cools part of the coolant in the cold storage device according to the detected water tank temperature, and keeps the water tank temperature at 25±1°C. At the same time, when the temperature of the phase change cold storage device is higher than 16°C, the second water pump works to transfer the heat from the cold storage device to the evaporator, the refrigeration cycle works, and the fan rotates to take away the heat. After the laser is turned off, when the ambient temperature is between -40 and 5°C: the first water pump works, and the coolant returns to the temperature-controlled water tank through the laser; the variable frequency pump changes speed according to the temperature of the temperature-controlled water tank to extract part of the coolant from the temperature-controlled water tank and cool it through the phase-change cold storage device, keeping the temperature of the temperature-controlled water tank at 25±1°C; the second water pump and fan continue to work, and the coolant flows through the second water pump, the phase-change cold storage device, and the radiator, transferring the heat of the phase-change cold storage device to the environment until the outlet temperature of the hot side of the phase-change cold storage device is less than 16°C; After the laser is turned off, when the ambient temperature is between 5 and +50°C: the first water pump, the variable frequency pump, the second water pump, and the fan work, the three-way valve switches to the evaporator circuit, and the refrigeration cycle works to cool the temperature-controlled water tank to 25±1°C and the phase change refrigerant outlet temperature to 16°C.

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