high heat fluxes, R404A, bulk boiling, spot evaporator
The influence of very high heat fluxes (105 to 106 W/m²) on the boiling behavior of R404A are investigated. By using a new evaporator design it is possible to change the evaporating effects even at these high heat fluxes to bulk boiling. This paper focusses on the experimental analysis of the new evaporator by varying the parameters geometry, mass flux, subcooling and fluid velocity. The results are compared with experimental works and mathematical models at lower heat fluxes. The results show, that fluid velocity, mass flux and geometry have high influence on the transferred heat flow, while the subcooling of the liquid phase has only a small effect.