Thermal-Gravitational Modelling and Scaling of Heat Transport Systems for Applications in Different Gravity Environments: Super-Gravity Levels & Oscillating Heat Transfer Devices

Several publications describe research carried out at NLR on the thermal-gravitational modelling and scaling of two-phase heat transport systems for spacecraft applications. They dealt with mechanically and capillary pumped two-phase loops. The activities pertained to pure geometric, pure fluid to fluid, or hybrid scaling between a prototype system and a model at the same gravity level, and between a prototype in micro-gravity and a model on earth. Recent publications also include the scaling aspects of a prototype loop for a Moon or Mars base application and a terrestrial model.

The work discussed here was carried out in the last couple of years. It concerns scaling to super-gravity levels, and was done because a promising super-gravity application for (two-phase) heat transport systems can be the cooling of high power electronics in spinning satellites and in military aircraft. In such aircraft, power electronics can be exposed, during manoeuvres, to transient accelerations up to say 12 g (120 m/s²). The discussions include pulsating two-phase loops and also oscillating (pulsating) heat transfer devices, for which several important applications in different acceleration environments have been identified.