Abstract
Heat transfer data was collected and correlated for developing transition flow and for natural and combined laminar flows of water in a vertical annulus, (
ε = 1.17), with isoflux inner wall and an adiabatic outer wall. For
Ra< 5×10
5
, the values of Nu were independent of Ra; beyond that Nu increased proportionally to Ra
0.25. For
1,000 <
Re < 4,000
, the values of Nu for bouyancy opposing flow were about 25 percent lower than those for bouyancy assisted flow. Transition flow was correlated for
4,000 <
Re < 10,000
.