Airframe Phase Change Heat Sink for Space-Saving Transpiration Cooling
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing transpiration cooling methods for airframes face challenges in sourcing coolant fluid, which occupies valuable space and requires substantial volume in high-speed systems, and there is a need for efficient cooling solutions to manage aerothermal heating.
Innovation Solution
Utilizing a Phase Change Material (PCM) heat sink that transitions from solid to liquid and gas to provide coolant gas for transpiration cooling, with a controlled vapor reservoir and controller to manage gas ejection and pressure, reducing space requirements and enhancing cooling efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If traditional transpiration cooling methods are used with external coolant fluid reservoirs, then cooling effectiveness is achieved, but valuable space is occupied and system complexity increases
Solution Approach 1:
The patent utilizes phase change material (PCM) that transitions from solid to liquid to gas phase. The PCM absorbs heat during phase transitions, providing cooling without requiring external fluid reservoirs. The phase change process occurs within the structural component itself, eliminating the need for separate coolant storage volumes.
Solution Approach 2:
The patent merges the cooling function with the structural component by embedding PCM directly into the airframe structure. This integration combines the structural support function and thermal management function into a single component, eliminating the need for separate coolant fluid reservoirs and reducing overall system volume.
2Temperature
If traditional transpiration cooling methods are used with external coolant fluid reservoirs, then cooling effectiveness is achieved, but device complexity increases
Solution Approach 1:
The patent merges the cooling function with the structural component by embedding PCM directly into the airframe structure. This integration combines the structural support function and thermal management function into a single component, eliminating the need for separate coolant storage reservoirs, piping systems, and associated control mechanisms, thereby reducing overall system complexity.
Solution Approach 2:
The PCM provides self-regulating cooling through its inherent phase change properties. When the structure heats up, the PCM automatically transitions from solid to liquid to gas, absorbing heat and providing cooling without requiring external control systems, pumps, or fluid management infrastructure.
3Strength
If conventional materials are used for airframe components under aerothermal heating, then structural integrity is maintained at high temperatures, but component mass and cost increase
Solution Approach 1:
The patent employs composite material construction where conventional structural materials are combined with phase change material. The conventional material provides structural integrity and heat resistance, while the embedded PCM provides thermal management. This composite approach allows the use of lighter conventional materials that would otherwise be unsuitable for high-temperature applications, reducing overall component mass.
Solution Approach 2:
The PCM transitions through phase changes (solid-liquid-gas) to absorb excess heat that would otherwise compromise structural integrity. This allows conventional lower-mass materials to maintain their strength properties by transferring thermal management burden to the PCM, which handles transient heating effects through phase transitions rather than requiring the structural material itself to withstand extreme temperatures.
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 PCM heat sink effectively cools airframe components, allowing the use of lower-cost, lower-mass materials and managing transient heating effects, while conserving space and improving thermal management.
Implementation Method 1
a phase change material configured to change phase to a gas when cooling the electronics
Implementation Method 2
PCM heat sink transfers energy from a heat source to the sink (PCM material) itself, using energy storage inherent in the phase change
Implementation Method 3
control ejection of the gas from the vapor reservoir to increase a thickness of a boundary air layer at the external surface
Implementation Method 4
A boundary layer of a thin layer of air forms as a system travels through the atmosphere
Data Source
AI summary
An apparatus and system are provided to provide transpiration cooling for an airframe. An airframe includes a body that contains circuitry, a phase change material (PCM) that changes phase to a gas when cooling the circuitry, a fluid reservoir that retains the PCM in liquid and gaseous form, a vapor reservoir that retains the gas, a thermal sensor that detects a temperature of an external surface of the body, and a controller that control ejection of the gas from the vapor reservoir based on the temperature to control a thickness of a boundary air layer at the external surface. The controller also controls flow of the gas from the fluid reservoir to the vapor reservoir via a valve based on pressure in the vapor reservoir detected by a pressure sensor.