MOMENTUM AND HEAT TRANSFER ANALYSIS OF ANNULAR AIR-WATER TWO PHASE FLOW IN A HORIZONTAL PIPE

           A theoretical study was performed to analyze the heat transfer and momentum in co-current annular, gas-liquid (air-water), two phase turbulent flow conditions in horizontal pipe using finite difference
numerical technique and eddy diffusivity concept.The concept of eddy diffusivity is reviewed, and theoretical comparison study is performed to predict heat transfer coefficient using various proposed models for eddy diffusivity for single phase turbulent flow.The influence of liquid superficial Reynolds number Re_sl, gas superficial Reynolds number Re_SG , liquid inlet temperature T_l,wall heat flux q'' and void fraction on the heat transfer coefficient, interfacial friction factor and temperature distribution in the liquid layer was studied and discussed. The heat transfer coefficient was calculated from the temperature calculation using finite difference method using MATHCAD and Q.BASIC Programs) to obtain the temperature profile axially and radially in the liquid layer and also the theoretical analysis included the estimation of friction factor. The analysis results were compared with experimental data.  The results showed that the finite difference numerical technique is an efficient way to predict the heat transfer ...