Drag computation and breakdown in power-on conditions

thrust-drag accounting system is proposed that makes it possible to calculate installation drag from computational fluid dynamics calculations. Given a numerical solution of the viscous subsonic or transonic flow around an aircraft configuration in power-on conditions, an entropy drag expression is derived. Therefore, a method for the computation and breakdown of the entropy drag in viscous and wave components can be extended and applied to powered configurations. The possibility of identifying spurious contributions improves the accuracy of the drag calculation for a given grid. Two applications are presented: a simple two-dimensional model problem and a transonic flow around an isolated nacelle with core and fan jets.