The numerical simulations of explosion and implosion in air: Use of a modified Harten's TVD scheme

Numerical simulations of explosion and implosion in air are carried out wit h a modified Harten's TVD scheme. The new scheme has a high resolution for contact discontinuities in addition to maintaining the good features of Har ten's TVD scheme. In the numerical experiment of spherical explosion in air , the second shock wave (which does not exist in the one-dimensional shock tube problem) and its subsequent implosion on the origin have been successf ully captured. The positions of the main shock wave, the contact discontinu ity and the second shock wave have shown satisfactory agreement with those predicted from previous analysis. The numerical results are also compared w ith those obtained experimentally. Finally, simulations of a cylindrical ex plosion and implosion in air are carried out. Results of the cylindrical im plosion in air are compared with those of previous work, including the inte raction of the reflected main shock wave with the contact discontinuity and the formation of a second shock wave. All these attest to the successful u se of the modified Harten's TVD scheme for the simulations of shock waves a rising from explosion and implosion. Copyright (C) 1999 John Wiley & Sons, Ltd.