Examination on Properties of Wrinkled Pipes in Helical Coil Heat Exchangers by CFD

- In the current manufacturing scenario, the Helical Coil Heat Exchangers (HCHE) are produced by three roll bending of pipes resulting in the formation of wrinkles on the inner edges of the pipes. The subject of this work is to compare the heat transfer characteristics and fluid flow behaviour in the wrinkled pipe and ideal pipe HCHE. Computational Fluid Dynamics (CFD) analysis for ideal pipe and wrinkled pipe heat exchangers are carried out to investigate heat transfer and fluid flow behaviour. The methodology of CFD is also validated using theoretical analysis. Constant properties and temperature-dependent properties of fluid passing in the heat exchanger are taken for modelling of CFD calculation. The final results revels that, wrinkled pipes have more heat transfer rate and effectiveness than ideal pipes, head loss is increased due to the presence of wrinkles and the rate of mass flow is reduced in wrinkled pipes due to reduction in volume inside the pipe