Heat Transfer Analysis in Annular Two Phase Flow Using Finite Difference Method

الملخص

Heat transfer in two phase flow is widely encountered in oil and gas industry in which heat is transported between two phase the fluid and the pipe wall with a rate depending on the hydrodynamic conditions.  In present work, theoretical study was carried out to predict the temperature distribution within the liquid layer in annular gas–liquid (air–water) of two phase flow in presence of heat flux under laminar flow conditions. The temperature distribution was evaluated at different values of liquid Reynolds number (Re_sL), gas Reynolds number (Re_sg), wall heat flux, and inlet liquid as well as gas temperatures. The finite differences technique was employed to solve the energy equation to obtain the temperature distribution in the liquid layer. Additionally, the effect of Re_sg and Re_sL on the liquid layer thickness was investigated and discussed. It was found that the presence of heat flux through the pipe wall leads to an increase in the liquid temperature asymptotically with the axial distance (z) depending on the radial distance (r). The maximum increase occurred in the liquid layers adjacent to the pipe surface layers and the minimum increase was at the interface. The fully developed temperature profile varied with radial distance (r) where the surface layers reached at L_t/d=5. However, the Lt/d for the layers nearest to the interface was less than 5.  At a particular (r) and constant Re_sg, the higher the Re_sL is, the higher the temperature will be. At a particular Re_sL and Re_sg, the liquid layer temperature distribution depends largely on the values of applied heat flux and the gas temperature.