Preliminary design of a self-deployable Pulsating Heat Pipe by means of a Shape Memory Alloy actuator

The preliminary design of thermally driven self-deployable pulsating heat pipe with Shape Memory Alloy (SMA) actuator is presented. The use of SMA wire allows the passive folding of the heat transfer device: the hot side of the heat exchanger acts as hot source for the SMA deformation. The system consists of a torsion-spring shaped Pulsating Heat Pipe tube portion (Al6063, 1.8 and 2.6 mm inner and outer diameter) and a SMA wire (0.5 mm diameter, closed and open configuration length 165 mm and 172 mm respectively). When the SMA wire is heated up by the hot source, it shortens inducing a moment on the PHP torsion spring that allows the PHP panel to rotate 90 deg.