Passive and compact liquid metal heat switch
A passive heat switch device is disclosed that includes a casing defining a closed channel, as well as a passive thermal actuator and liquid slug positioned inside the closed channel. The closed channel includes a heat conducting region made of a heat conducting material and an insulating region made of an insulating material. The passive thermal actuator is thermally coupled to the heat conducting material of the heat conducting region and extends into the insulating region of the closed channel. The passive thermal actuator deforms when an actuator temperature falls within a switching temperature range. The liquid slug is positioned within the closed channel and contacts at least a portion of the passive thermal actuator and the closed channel and is configured to move along the closed channel between the insulating region and the thermally conductive region in response to deformation of the passive thermal actuator.