Non-Vaporizing and Vaporizing Diesel Spray Evaluation with Experimental and Computational Approaches

Abstract

Experimental and numerical modeling of diesel spray is necessary to understand the idea of efficient combustion and injection strategies in diesel engines. The current study aims to demonstrate the experimental and computational modeling of diesel spray under non-evaporating and evaporating conditions using three single hole injector diameters i.e. 0.133mm, 0.122mm and 0.101mm with injection pressure and injection quantity of 120 MPa and 5 mm3, respectively. First, the non-evaporating experiments are performed in high-pressure high-temperature constant volume vessel where the spray images are captured with High-Speed Video (HSV) camera using Diffused Background Illumination (DBI) method. However, evaporating spray experiments implement LAS technique to measure mixture concentration as well as visualize liquid and vapor phases of evaporating spray. The experimental results are then validated with computational simulation using AVL FIRE commercial CFD code. The CFD code uses Reynold’s Averaged Navier Stokes (RANS), KHRT and Dukowicz model as turbulence, spray breakup and evaporation models, respectively. Good agreement can be found between experimental results and CFD simulation in terms of spray tip penetration, spray angle and spray cone angle for non-evaporating case and equivalence ratio distribution, liquid/vapor penetration lengths and evaporation ratio for evaporating sprays. Thus, this work can be considered as successful validation for CI engine under similar spray conditions.