Drone Thermal Management Case Study
The Design Challenge
Drones are becoming increasingly useful to large corporations, military,and every day consumers across the globe. As technology advancesthese flying robots are utilized for a number of functions such as searchand rescue missions, security surveillance, medical analysis, and in thiscase, internet access to remote areas. Drones pose their own set ofthermal challenges. These are compounded when additional devices areadded to supply internet capabilities to underdeveloped countries, oftenin rugged environments.
The company working to provide this access developed drones withinternal components that include an array of power supplies, motors,and modems which dissipate heat inside an attached dome. On theunderside of its circuit board an antenna is attached with a protectivedome around it. Because the environment would be high in velocity,temperature, and altitude, there was some doubt as to whether thatproduct design would succeed. This doubt caused the company to reachout to the Aavid, Thermal division of Boyd Corporation, to perform athermal and flow analysis of the drone.
The Aavid Solution
Although there are many components needed for mounting theelectronics, these play no role in thermal and flow analysis and wouldonly create mesh issues and make the computational time much bigger.
There were significant challenges to performing a flow only analysis ofthe entire fuselage such as high velocity and the change in fluidproperties due to altitude. Additionally, turbulence solvers needed to berun and evaluated to ensure the success of the CFD analysis.
Upon completion of the CFD, the turbulence model was applied. In orderfor all pieces of the drone to be cooled properly, the model required acomplex mesh – mostly due to the unbalanced ratio of fuselage size andthickness to the miniscule electronic parts. To further reduce the meshcount, hollow blocks were modeled for the components thatcontributed only to the flow obstruction.
From this juncture, Aavid was able to work with the customer toredesign the drone to accommodate the finding. On this project, flowanalysis was actually more critical to evaluating and redesigning thedevice than thermal analysis. Both flow and thermal analyses are oftencrucial to design success and are recommended for any electronics thatare being used in new and innovative ways in nonstandardenvironments, such as these drones.