Abstract: A heat seeking missile decoy device mounted on a military vehicle to change the infrared signature of the military vehicle. The device is at ambient temperature when stored on the military vehicle. When a heat seeking missile is fired at the military vehicle, the decoy device deploys and increases in temperature, changing the infrared signature of the vehicle and causing a hot spot away from vulnerable components of the vehicle. The hot spot radiates in the infrared in an area that is away from vulnerable parts of a military vehicle, drawing the heat seeking missile toward it. The termination trajectory of the heat seeking missile is at the end of the decoy device and not the vulnerable parts of the military vehicle. The energy required to heat the device is passive waste energy from the vehicle engine exhaust.

Abstract: A thermal energy transfer device having controllably variable thermal conductance comprises a reflux heat pipe having a capillary wick therein, an evaporator and a condenser zone, a circulating supply of working fluid which is controlled by a bendable section in the heat pipe body and an external device to control the bend in the heat pipe body, thereby controlling the amount of liquid returning to the evaporator. As returning liquid condensate is trapped in the center of the deformed tube, less liquid is available for evaporation in the evaporator. This results in a low liquid level that saturates only a portion of the evaporator wick. This results in higher thermal impedance. If the heat pipe body is deformed so that all liquid is trapped in the deformed portion, no liquid is available in the evaporator and there is a high thermal impedance.