Elimination of a non-oscillatory instability in a retarded potential integral equation

摘要: Abstract This paper deals with the unstable behaviour of an acoustic boundary element model. The model, based on a marching time (MOT) algorithm, uses hypersingular derivative Green method. It is able to cope open or closed diffracting objects. These objects are rigid can be deformed. When long enough computation carried out, pressure magnitude shows exponential growth, which unrealistic behaviour. In we show that faced numerical instability static in cavities. A simple processing method using eigenelement decomposition ‘ad hoc’ matrix suffices correct problem without damage other components result. related more general dedicated problems.