Steady low Mach number flows: Identification of the spurious mode and filtering method

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 at price computation system, accuracy an inaccurate flow can be greatly improved by method.