ISSN Online: 2377-424X
ISBN Print: 0-85295-345-3
International Heat Transfer Conference 10
NUCLEATE POOL BOILING AND CHF OF REFRIGERANT/OIL MIXTURES IN THE CONFINED SPACE BETWEEN TWO VERTICAL PLATES
Resumo
The nucleate boiling and CHF of pure R-113 and of
mixtures of R-113 and SUNISO 3GS oil were experimentally
studied in the confined space between a vertical, 30 mm wide, 120 mm high, heated surface and an opposing, unheated plate. The parameters investigated were the gap size (2 mrn through 5 mm), the oil concentration (1% through 7% by mass), and the geometry of the unheated plate (solid or perforated). The confinement (solid plate) did not affect nucleate boiling of pure R-113 significantly whereas the CHF decreased with
decreasing gap size. The oil had only a minor effect on low
flux boiling but caused a serious degradation of high flux
boiling. This deterioration was more severe for smaller gap sizes. The CHF increased with increasing concentration, however accompanied by increasingly larger superheats. The performance with the perforated plates was not significantly better than with the solid plate at the same gap size, their use being justified only when the gap size cannot be increased.