Numerical solution of homogeneous double pipe heat exchanger: Dynamic modeling

Dynamic modeling of a double-pipe heat exchanger is the subject of the current study. The basis of this study is the same velocity of vapor and liquid phases or, in other words, homogeneous phase, in the annulus part of the exchanger. The model can predict the temperature and vapor quality along the axial pipe from the pipe inlet up to a distance where steady state conditions are achieved. The simulation is conducted for two modes of co- and counter- ow in a one dimensional transient system. The physical properties of water are estimated from empirical correlation and a saturated vapor table with cubic spline interpolation. The exchanger model, which is a set of Ordinary Dierential Equations (ODEs), ODEs and algebraic equations, has been solved numerically. Modeling results have been investigated for dierent operating times and two modes of co- and counter-curren