Development of a Liquid Cooling Garment for the NDX-1 Prototype

The NDX-1 is a planetary space suit concept that was built in 2006 at the Space Suit Laboratory of the University of North Dakota. The prototype has been successfully tested conducting surface operations jointly with NASA in a number of extreme environments around the world. However, some its principal interacting elements are still being subjected to modifications to improve its performance. Such is the case of the liquid cooling garment, built to be used under the suit to remove the metabolic heat produced by the subject. The garment is currently part of an external heat exchange system, whose working fluid is forced by means of a multi-purpose pump. The objectives of this research were: to calculate the heat removal capacity of the system applying a simple heat exchange model; to compare this theoretical value with the values obtained when using thermocouples to register the inlet and outlet temperature of the LCG; and to determine if the capacity of the mechanical pump being currently used is suitable for this system. Results showed that the thermodynamic model applied was accurate and that the system is able to maintain its mean heat removal capacity with a less powerful pump. These observations are crucial for the design of a heat exchanger that will be included in the NDX-1 portable life support system to make the garment operative.