Variable Area Heat Pipe for Aircraft Thermal Management
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing heat transfer systems in aircraft, such as air-cooled oil coolers, are often large and heavy, increasing the weight of the aircraft and requiring efficient heat dissipation methods to prevent overheating in starter/generators.
Innovation Solution
A variable area heat transfer device comprising a thermally conductive pipe and a heat transfer element that moves between retracted and extended positions based on temperature or pressure changes, increasing its length and heat radiating capability, and utilizing a working fluid within a cavity to absorb and dissipate heat effectively.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If a traditional air-cooled oil cooler is used to dissipate heat from the starter/generator, then heat dissipation is achieved, but the device becomes large and heavy, increasing aircraft weight
Solution Approach 1:
The heat transfer device employs a movable heat transfer element that can slide between retracted and extended positions along the thermally conductive pipe. This dynamic configuration allows the device to adjust its heat radiating surface area based on thermal conditions, achieving effective heat dissipation when needed while minimizing the device's physical footprint and weight when not in use, thereby resolving the contradiction between heat dissipation capability and aircraft weight
Solution Approach 2:
The device changes its operational parameters by varying the extension position of the heat transfer element in response to temperature and pressure changes within the closed loop system. When the starter/generator requires cooling, the element extends to maximize heat transfer surface area; when cooling is not required, it retracts to minimize weight and drag, thus adapting the heat dissipation capability to actual thermal demands without permanently increasing aircraft weight
2Temperature
If the heat transfer device extends to increase heat radiating capability, then heat transfer efficiency improves, but device length and drag increase
Solution Approach 1:
The heat transfer element is designed to be movable along the thermally conductive pipe, enabling the device to dynamically extend its length only when heat dissipation is required. During normal operation or when cooling demand is low, the element remains retracted, keeping the device compact and minimizing aerodynamic drag. When thermal loads increase, the element extends to provide the necessary heat radiating surface area, thus resolving the contradiction between heat transfer efficiency and device length
Solution Approach 2:
The heat transfer element is nested within or alongside the thermally conductive pipe structure, allowing it to be stored in a compact configuration when not in use. The element can slide out or extend from the main body of the device only when heat dissipation is needed, effectively nesting the extended functionality within the compact base structure, thereby minimizing the device's overall length and drag during normal flight conditions while maintaining the capability for enhanced heat transfer when required
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 device provides efficient heat transfer with reduced size and weight, automatically adjusting its heat transfer area based on temperature and pressure, enhancing cooling efficiency while minimizing drag and aircraft weight.
Implementation Method 1
A cavity for containing a working fluid is at least partially defined by the thermally conductive pipe
Implementation Method 2
The orifice is configured to control a flow of vaporized working fluid around said closed loop fluid conduit
Implementation Method 3
The orifice is configured to control a flow of vaporized working fluid around said closed loop fluid conduit
Implementation Method 4
the heat transfer element is configured to move between the first position and the second position as a function of a temperature of said thermally conductive pipe
Implementation Method 5
the heat transfer element configured to move between the first and second positions as a result of a variable pressure within the cavity defined by said thermally conductive pipe
Implementation Method 6
a thermally conductive pipe and a heat transfer element slidably coupled to the thermally conductive pipe
Data Source
Figure 1
Figure 2
Figure 3
AI summary
Heat transfer devices (322) are described. In one example, a heat transfer device for installation in a system having a heat generating element within the system away from which heat is to be transferred is described. The heat transfer device (322) includes a heat pipe (330) having a first portion, a second portion, and a working fluid contained within the heat pipe for transferring heat from the first portion to the second portion. The first portion is disposed in proximity with the heat generating element. The second portion is coupled to the first portion. At least part of the second portion is disposed outside the system to dissipate heat from the heat generating element and the second portion may be variably extended outside the system. ( Fig. 3 )