The liquid droplet radiator
Abstract
A new type of radiator which uses a recirculating stream of liquid droplets as a radiation element in place of the solid surfaces used in conventional tube and fin space radiators is discussed. By virtue of the large surface to volume ratio of small droplets the liquid droplet radiator (LDR) has the potential of being many times lighter than the lightest solid surface radiator yet developed (heat pipes). In addition the LDR may be much more simply and economically deployed since the radiating element is transported as a liquid. Preliminary studies of the physics and engineering of the LDR have not revealed any exceptional obstacles to development of a practical LDR based on existing technology. Generation of droplets may utilize the methods developed for ink-jet printing, and collection devices using rotation to simulate gravity appear workable. Liquids were identified which have low enough vapor pressures that evaporation losses over durations of tens of years are tolerable. Liquid tin is best for heat rejection between 500 K and 1000 K, tin eutectics between 370 K and 600 K, and silicone oils between 260 K and 400 K.
- Publication:
-
Prime-Power for High Energy Space Systems
- Pub Date:
- 1982
- Bibcode:
- 1982pphe....2U....M
- Keywords:
-
- Drops (Liquids);
- Evaporative Cooling;
- Spacecraft Radiators;
- Cooling Systems;
- Evaporation;
- Mercury (Metal);
- Silicon;
- Tin;
- Vaporizers;
- Fluid Mechanics and Heat Transfer