Evolution of an Additive Manufactured Heat Exchanger for PLSS 2.5

The next generation of extravehicular mobility unit (EMU) will require lightweight, high performance components in order to minimize the mass, volume and power of its portable life support system (PLSS). One component under development for this application is a gas / liquid heat exchanger that will cool the breathing gas delivered to the crewmember’s helmet. This technology has been gradually matured over the past several years. It started with a vacuum brazed compact heat exchanger used in NASA’s PLSS 2.0 and continued with two selective laser sintered heat exchangers, which were built using Inconel and titanium. This paper describes how the use of additive manufacturing has reduced weight, volume, cost, and manufacturing lead time of this line of heat exchangers. It also shows how performance test results have good agreement with the computational models.