Unified Model of Heat Transfer in Gas/Oil/Water Pipe Flow

Abstract

Abstract In oil and gas production, the heat transfer process occurs from reservoir porous media to surface facility. Accurate modeling of convective heat transfer coefficient of pipe flow will improve production facility design and help tackle flow assurance problems such as gas hydrates, scale, wax deposition, heavy oil production and transportation. This paper presents a unified gas/oil/water heat transfer model for pipe flow at inclinations from −90° to +90°. It provides a new approach to three-phase pipe flow mechanistic heat transfer modeling. In this approach, three-phase hydrodynamic parameters were calculated first using Zhang and Sarica (2006) unified model. Then, the heat transfer models were developed for gas/oil/water three-phase flow patterns. The phase distributions were described as gas/liquid flow pattern and oil/water mixing status. Energy balance, temperature differences and variations were analyzed for each case. Overall heat transfer coefficients were derived and programmed. To test the program implementation, a synthetic field case was created and run. The temperature prediction was reasonably compared with commercial steady-state and dynamic multiphase flow simulators. The gas/oil/water heat transfer model was then compared with an oil/gas two-phase experimental data from Manabe (2001) for different flow patterns in a 52.5-mm inner diameter pipe from horizontal to upward-vertical inclinations. Overall performance of the present model was good. Convective heat transfer coefficient prediction was within 22% absolute average relative error. Mixture temperature was predicted within 1.5% absolute average relative error. After comparing with two-phase flow data, sensitivity of heat transfer coefficient to water cut was analyzed by changing the water cut from 0.0 to 1.0 under different flow conditions. Predicted convective heat transfer coefficient was sensitive to flow pattern, water cut and flow rate changes. Generally, the predicted convective heat transfer coefficient increases as water cut increases for the same flow pattern.