Three-Dimensional Simulation of Heat Transfer in Diesel-Spray Flame Impinging on Flat Wall using Skeletal Mechanism of n-Tridecane

Abstract

The diesel spray flame impinging on a flaw wall is simulated to validate the prediction of the wall heat transfer. The fuel injected is modeled by Lagrangian approach with DDM (Discrete Droplet Model). The gas phase is simulated by RANS with RNG-k-ε and wall functions. To improve the computational efficiency, several computation methods are incorporated into the spray simulation code based on OpenFOAM, such as massive parallel computing, the smaller skeletal mechanism of n-tridecane containing 49 species and 85 reactions, SpeedCHEM, and AMR (Adaptive Mesh Refinement). Thus, we obtained computational results in relatively short time. The computational results show the diffusion-like flame distributes at spray periphery in the injection duration. After the end of injection, the internal spray region is burned to entrain the ambient air into the internal spray from the upstream of spray. The heat loss is increased with increase in the injection pressure, as shown in experimental results. The heat losses of experimental and computational results are proportional to Reynolds number at nozzle exit to 0.15 and 0.24, respectively.