Use of CFD to predict the performance of a heat treatment furnace

In this paper, a mobile heat treatment furnace was simulated by using CFD to investigate thermal performance of the furnace and the heating process of the metal pieces. The furnace is used to heat treat dredging pumps and impellers to obtain the required microstructure and mechanical properties through stress relief, annealing, hardening and tempering. Since the temperature evolution inside the metal piece cannot be tracked in practice, CFD simulation provides a useful tool to predict the temperature evolution within the metal pieces during the heat treatment. The current CFD model consists of turbulent combustion, thermal radiation, and conjugate heat transfer. Temperature measurement was carried out to provide thermal boundary conditions and calibrate model parameters. An overall energy balance indicted a relatively low energy efficiency of the furnace. To improve energy efficiency design changes were made with the model. Reducing the amount of excess air will also save a lot of energy and thus cost in production. Heating of the furnace by means of radiation plates proved to be a good alternative