ISSN Online: 2377-424X
ISBN Print: 0-85295-345-3
International Heat Transfer Conference 10
HEAT TRANSFER AND LIQUID SOLID CONTACT DURING THE RAPID QUENCHING OF THIN WIRES IN WATER AND CaCI2/ WATER SOLUTION
Abstrakt
The rapid quenching of thin horizontal platinum wires falling at a constant speed was studied experimentally with pure water and CaCl2 solution as quenching liquids. The boiling curve was obtained from the cooling curve. For pure water, the boiling curve had two local minimum-heat-flux points. Measurements of liquid-solid contact showed that a remarkable liquid-solid contact began at the first (higher wall superheat) minimum-heatflux
point M1. The Nusselt number at the MI point decreased
with increasing liquid subcooling and reached a constant value irrespective of wire diameter. The wall superheat at the second (lower wall superheat) minimum-heat-flux point M2 was approximately 350 K for water and increased considerably with increasing CaCl2 mass fraction. For the wall superheat below the M2 point, the heat flux also increased considerably with increasing CaCl2 mass fraction.