Vertical Boiling Cooling Device for Power Semiconductors
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional boiling cooling devices for power semiconductors face limitations in heat flux due to low thermal conductivity of thermal conductive lubricants and increased pressure loss from complex fin shapes, which restricts thermal resistance reduction and is not sufficient for next-generation devices like SiC-MOSFETs that require higher critical heat flux.
Innovation Solution
A boiling cooling device with vertically disposed power semiconductors, featuring heat radiating plates with fine longitudinal or mesh-shaped grooves that promote air bubble creation and rise, allowing for efficient heat transfer without a pump, using refrigerant-filled heat receiving jackets connected to a condenser via forward and return pipes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If thermal conductive lubricant is used between power semiconductor and water cooling tube, then assembly is facilitated, but thermal resistance increases due to low thermal conductivity (about 3 W/mK)
Solution Approach 1:
The invention removes the thermal conductive lubricant layer from the heat transfer interface. By directly contacting the heat radiating plate with the refrigerant in the heat receiving jacket, the lubricant layer that causes thermal resistance is eliminated, while assembly remains feasible through the direct contact design
Solution Approach 2:
The refrigerant serves as an intermediary medium that directly contacts both the heat radiating plate and the cooling system. Instead of using lubricant as a mediator, the refrigerant itself performs the heat transfer function, eliminating the thermal resistance issue while maintaining assembly capability
2Reliability
If fin shape of water cooling tube is made complicated to improve heat transfer, then heat radiation performance improves, but pressure loss increases
Solution Approach 1:
The invention utilizes phase transition of the refrigerant (boiling and evaporation) to transfer heat from the power semiconductor. This phase change mechanism achieves high heat radiation performance without requiring complicated fin structures, thereby avoiding increased pressure loss
Solution Approach 2:
The invention replaces the mechanical heat transfer system ( fins, forced convection) with a phase change-based heat transfer system. The boiling and evaporation process naturally achieves high heat transfer efficiency without mechanical complexity, reducing pressure loss
3Reliability
If circulating amount of refrigerant is increased to reduce thermal resistance, then heat transfer improves, but pump capacity must be increased, raising cost and space requirements
Solution Approach 1:
The refrigerant circulation is achieved through natural convection driven by density differences during phase change, without requiring an external pump. The system serves itself by utilizing the inherent physical properties of the refrigerant to maintain circulation and achieve low thermal resistance
Solution Approach 2:
The invention replaces the mechanical pump-based circulation system with a natural convection system driven by phase change. This substitution eliminates the need for high pump capacity while achieving improved heat transfer and reduced thermal resistance
4Device complexity
If conventional boiling cooling is used, then pump-free operation is achieved, but critical heat flux is limited to about 180 W/cm², insufficient for next-generation devices
Solution Approach 1:
The invention utilizes phase transitions (boiling and evaporation) of the refrigerant to achieve high critical heat flux. By optimizing the heat receiving jacket design and refrigerant contact, the system achieves pump-free operation with critical heat flux exceeding 500 W/cm², suitable for next-generation power semiconductors
Solution Approach 2:
The invention changes the physical parameters of the heat transfer system by using direct refrigerant contact and phase change mechanisms. This allows achieving high critical heat flux values (over 500 W/cm²) while maintaining pump-free operation, resolving the limitation of conventional boiling cooling
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The solution significantly improves heat flux and thermal resistance, achieving a critical heat flux of about 500 W/cm², enhancing heat radiation performance and reducing thermal resistance, making it suitable for high-power semiconductor cooling applications.
Implementation Method 1
a boiling cooling device capable of efficiently cooling a power semiconductor
Implementation Method 2
the refrigerant is boiled and evaporated by heat of the semiconductor device
Implementation Method 3
heat radiating plates provided on both left and right side faces of the power semiconductor
Implementation Method 4
flows into a condenser 320, is cooled in a cooling fan, is liquefied
Implementation Method 5
the air bubbles generated on a horizontal plane of the vaporization promoting plate are not largely grown
Data Source
AI summary
A boiling cooling device e includes a power semiconductor that is vertically disposed, heat radiating plates provided on both side faces of the power semiconductor, heat receiving jackets provided at both sides of the power semiconductor and covering the heat radiating plates, refrigerant filled in the heat receiving jackets and being in contact with the heat radiating plates, a condenser connected to the heat receiving jackets, and fine longitudinal grooves formed on a heat radiating face of the heat radiating plate and extending in a vertical direction, where creation of air bubbles is promoted by heat generated in the power semiconductor and by the fine longitudinal grooves, the created air bubbles rising and passing through a forward pipe and then reaching the condenser to be liquefied, such that liquid is returned to the heat receiving jacket via a return pipe.