CHARACTERISTICS OF VERTICAL ANNULAR 2-PHASE FLOW WITH LOCAL LIQUID FALL-BACK

A new analytical method for two-phase flow is proposed, in which the most easily occurring and, thus, most stable two-phase flow situation is assumed to be realized. Flow structure is considered to be self-controlled so as to realize the most stable two-phase flow situation. In the present study, the flow situation with smaller pressure energy consumption rate for unit mass of penetrating two-phase fluid through each channel cross section is assumed to be more stable. In addition, two-dimensional turbulent flow analysis is applied to the annular flow regime in which partical or total downflow of the liquid film is allowed. Experimental analysis based on the data from an air-water two-phase flow experiment, which was performed at atmospheric pressure and room temperature, indicated the applicability of the proposed analytical method.