One-dimensional Analysis Techniques for Pulsed Jet Flow Distribution Systems

Abstract

Active flow control offers much promise for improved aircraft performance by delaying stall, increasing lift, reducing drag, enhancing combustion, and decreasing jet noise. Steady or pulsed blowing may be applied optimally at only those discrete locations where the control system senses it is required to maintain attached flow. The steady pulsatile flow of internal combustion engine exhaust systems has many similarities to pulsed jet active flow distribution systems. Pulsatile flow in internal combustion engines has been analyzed by Blair (1999). This analysis method is being extended to pulsed jet blowing systems. A general-purpose one-dimensional code is developed to simulate the wave transmission and establish system dynamic parameters. The simulations have been carried out for two test cases found in literature. The simulation is conducted for various wave frequencies. Effect of frequency on pressure and velocity is also demonstrated. Usefulness of this one-dimensional code as an analysis tool is demonstrated.