ID#: 79
Abstract Title: A Numerical Study of Hydrogen/Air Detonation Using a Pressure Dependent Stanford Model: Formation and Burning of Unreacted Gas Pocket
Session Title: Cellular Structure I
Session Date: 7/30/01
Session Start Time: 8:55 AM
Contributing Author: Tsuboi, N.
Organization: Fujii Lab., High Speed Aerodynamics
Country: Japan
Authors: Nobuyuki Tsuboi, Hiroshi Shimizu, A.Koichi Hayashi, Yoichiro Matsumoto
Short Abstract: Two-dimensional numerical simulation for H2/Air detonation was performed by using a pressure dependent Stanford model. The governing equations are made from the Euler equations with the mass conservation of 9 species and with 18 elementary reactions. The equations are explicitly integrated by second-order Strang type fractional step method. The source terms with chemical reaction are treated in a linearly point-implicit manner. As for a numerical flux scheme, Harten-Yee non-MUSCL type TVD scheme is used. The Stanford model has 9 species and 18 elementary reactions with pressure dependence. The model includes H2O2 and HO2 chemistry near the second and third explosion limit, which is necessary for ignition at ram accelerator pressures but lacking in certain finite chemistry models currently in use. The rate coefficients for H2O2 and HO2 reactions has a pressure dependent rate coefficient defined by method of Troe. The results showed that the detailed mechanisms of the formation and the explosion of the unreacted pocket was revealed clearly and that the isolated unreacted pocket were ignited from its rear side by the intersection of the transverse shock. The maximum pressure history and the local specific energy release history showed that the transverse shock intersection and the explosion of the unreacted pocket cause the weak longitudinal and transverse tracks.