Multi-phase flow in heat exchangers in low-gravity conditions
Fluid Physics: Fluid and interface physics
45th ESA Parabolic Flight Campain
H. Salvador Fouz (1), S. Marcos Andrada (1), E. Gozález Casas (1), T. Povedano Moreno (1)
|(1)||Universidad Politécnica de Madrid (UPM)|
C/ General Díaz Porlier, 15 3º Izq
The objective of this project is to study the different physical effects that take place in fluid behaviour inside heat exchangers. These effects are overlapped in normal gravity conditions by natural convection. The data collected will be used to improve the technology of heat exchangers taking advantage of these minor effects.
In microgravity conditions, floatability forces are not present, and so bubbles that form over the heater surface are not replaced by cooler liquid. It is expected that bubbles will remain on the surface till the point of creating a vapour blanket that will block the process, thus releasing heat. Different techniques will be tested to solve this problem. The project also has an educational orientation, solving questions like “Is it possible to cook in microgravity conditions?”, just by analyzing if the whole fluid temperature can be raised or heat transfer will be blocked by the vapour blanket.
To study these effects, the project is sub-divided in four different experiments:
- Zero-G Bubble behaviour: will study the formation of a gas bubble rising from a heated plane surface and the formation of the vapour blanket.
- Capillary effect: will study the effect of capillarity in the growing two-phase front and its equilibrium geometry within different narrow channels.
- Spherical Homogeneous nucleation: Spherical simplified model for homogeneous nucleation will be observed by overheating a single point within the liquid.
- Turbo pumped loop (TPL): Technical demonstration of a turbo forced two-phase heat exchanger. Power will be taken from vapour expansion in a turbine to move a pump which forces fluid back to the heater section. It intends to be a more powerful, auto-adjustable and non-gravity dependant liquid refrigeration alternative for space devices.
|In-flight experiment footage|
Olivier Minster (e-mail: email@example.com)