A magnetic fluid based thermal connector for avionics chassis
Abstract
[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT AUTHOR'S REQUEST.] The University of Missouri, Columbia, has participated in the DARPA/ONR sponsored RevCon Challenge to demonstrate an innovative field reversible thermal connector to replace the current industry standard wedgelock for edge cooled electronics. Wedgelocks mechanically secure edge cooled electronics cards to a cooling block, but having a dry interface and little contact surface area leads to poor heat transfer from the card to the cooling block. Seeking marked improvement in thermal performance, a novel thermal connector has been developed utilizing a magnetorheological (MR) fluid. The MR fluid provides a liquid interface for vastly improved heat transfer. Also, utilizing an applied magnetic field the fluid shear stress can be increased causing complete mechanical restraint of the electronics card while providing vibration damping. The initial University of Missouri RevCon design is discussed, and its evolution into the current MR fluid thermal connector is presented. The unique heat transfer characteristics of the selected MR fluid are presented, including the controllable variation of fluid thermal conductivity with an applied magnetic field. Thermal performance has been simulated, evaluated experimentally, and compared directly to the industry standard wedgelock. Also, the MR fluid interface has been investigated as a means to provide vibration damping for the electronics card, and damping characteristics are discussed.
Degree
M.S.
Thesis Department
Rights
Access is limited to the campuses of the University of Missouri.