There are unfavorable conditions such as constantly changing working and frequent disturbances that affect Mach number control in wind tunnel flow fields. As the proportional, integral differential (PID) parameters need to be re-tuned for each of a tunnel, operational costs tunnels very high. Therefore, lower these costs, genetic algorithm was utilized tune PID achieve multi-mode field. In this...

The aim of this article is to thoroughly identify the spurious mode that jeopardizes convergence usual upwind numerical schemes for compressible flows when Mach number goes 0. We show long time limit a wave system whose properties and discretization depend on scheme used system. Once identified, filtering method developed removing it from solution stationary low flow. Numerical results confirm ...