Determination of Temperature Distribution during Heat Treatment of Forgings: Simulation and Experiment

Combination of transient computational fluid dynamics simulations of a gas-fired heat treatment furnace and experimental validation were carried out to investigate the applicability of equilibrium non-premix combustion model and the effect of different turbulence models on the thermal interactions inside the furnace. Thermal interactions analyses based on temperature measurements on an instrumented large size block were performed at different locations of the forged blocks. A good agreement, with a maximum deviation of about 4%, was obtained using a one-third periodic model of the furnace. Results indicated that the chemical equilibrium non-premix combustion model could effectively be employed for combustion modeling and subsequently products' temperature predictions. A temperature non-uniformity of up to 331 K was determined on the surface of the forgings due to furnace geometrical design and loading pattern. Prediction of turbulence dissipation rate to turbulence kinetic energy ratio by different turbulence models could significantly affect the combustion predictions and product temperatures. Reynolds stress model was found as the most reliable turbulence model and the realizable k-epsilon model could reasonably predict the global block temperature. While, Shear stress transport k-omega model over-predicted the block temperature, it showed reasonable results in stagnation region.