DETERMINATION OF OPERATION ENVELOPES FOR CLOSED, TWO-PHASE THERMOSYPHONS

摘要

A concern in the design and operation of closed, two-phase therosyphons (CTPTs)is determining the initial filling ratio of the working fluid, as a function of CTPT dimensions, type and vapor temperature of working fluid and power throughput, to maximize performance, while avoiding potential dryout in the evaporator section. A one-dimensional, steady-state model is developed for determining the operation envelopes of CTPTs, in terms of the above parameters. The CTPT operation envelope is basically an enclosure with three boundaries. The lower boundary corresponds to when the liquid film thickness in the evaporator reaches a critical value-beyond it the liquid film could dry out-while the upper boundary coorresponds to when the expanding liquid pool, due to boiling, fills the entire evaporator.