Transient Modeling of Loop Heat Pipes

Triem Hoang, Jentung Ku
2003 1st International Energy Conversion Engineering Conference (IECEC)   unpublished
Unlike heat pipes, Loop Heat Pipe (LHP) operation involves highly complex thermal-hydraulic processes that cannot be modeled intuitively. Furthermore, when incorporated to a spacecraft system thermal model, the LHP transient behavior is even more difficult to predict due to the time-varying heat exchange with the spacecraft and the surrounding. The desire of thermal analysts to simulate accurately transient behaviors of LHP systems necessitated the development of a theory for LHP operation (to
more » ... LHP operation (to be presented in this paper). Accordingly, a set of governing equations were derived from the basic conservation laws of mass, momentum, and energy. But more importantly, mechanisms driving both mass and heat transfer in the LHP capillary pump were proposed and modeled mathematically. Calculations of the pump heat leak, made by the model, were verified with available test data. Preliminary assessment of the mass and heat transfer model indicated that it predicted the heat leak well. Computer simulations of an LHP-based TCS were also carried out, essentially to verify the theory predictions. Calculated temperatures of the loop were well within 5 O C of available test data.
doi:10.2514/6.2003-6082 fatcat:zzzkc7ff75azhkbv3zjfwlf5ym