FLOW BOILING IN HORIZONTAL TUBES - PART 3 - DEVELOPMENT OF A NEW HEAT-TRANSFER MODEL-BASED ON FLOW PATTERN

A new heat transfer model for intube flow, boiling in horizontal plain tubes is proposed that incorporates the effects of local two-phase fl ow patterns flow stratification, and partial dryout in annular flow. S ignificantly the local peak in the heat transfer coefficient versus va por quality can now be determined from the prediction of the location of onset of partial dryout in annular flow. The new method accurately predicts a large, new database of flow boiling data, and is particular ly better than existing methods at high vapor qualities (x > 85 percen t) and for stratified types of flows.