Energy Equation Derivation of the Multiphase Flow Pipeline

In the simulation of oil-gas pipeline multiphase flow,thermodynamic computation was an important process interacting with the hydraulic calculation,and it influences the convergence of the program and the accuracy of the results.The form of the energy equation was key to the thermodynamic computation.Through analysis of energy conservation,the energy equation was derived.This new energy equation has considered many factors,such as Joule-Thomson effect,pressure work, friction work,phase change heat transfer,and heat transfer with the pipe wall.So it was an overall form of energy equation, which could reflect the actual fact of multiphase pipeline accurately.This model was incorporated into the TPCOMP,and a simulation was carried out with a practical pipeline,Yingmai-Yaha multiphase pipeline,and the temperature result was compared with OLGA.The results show that this model has simulated the temperature distribution very well.It is better than the original TPCOMP thermodynamic model,and the result is similar with that of OLGA,so the accuracy of the model is evident.