Failure Analysis of Heat Exchangers with a Valid CFD Simulation

Abstract

Energy efficiency, safety and stable operation of units are the most crucial aspects in every industrial process. In this study, Computational Fluid Dynamics (CFD) simulations were used to study heat transfer in a laboratory-sized tubular heat exchanger. A partly 2D axisymmetric and mainly 3D model of the heat exchanger was created and validated with several simulation in different operating points of heating capacity and volume flow. The results of the simulations were compared to experimental data to validate the model. The inlet and outlet temperatures were measured with Pt100 temperature probes, and the surface temperatures were measured with an infrared camera. The heat transfer coefficient was determined based on the surface measurements The validated model was applied for the investigation of performance losses of heat exchanger due to fouling caused by particle deposits along the tube which caused reduced heat transfer surface or performance and a failure of heating wire which caused reduced heating performance, hence altered heat and flow characteristics through the equipment. The results provide useful information not only in the design processes but the operational lifetime as well.