Multi Wavelength Laser Beam Propagation Close to a Down-Scaled Jet Engine Exhaust (Utbredning av Laserstaelar Med Olika Vaeglaengder i Naerheten av Plymen fran en Nedskalad Jetmor)

摘要

Laser beam propagation in severe environments such as the turbulent flow near an aircraft needs to be studied to predict the performance of laser countermeasure systems. The jet engine plume may introduce severe perturbations on installed countermeasure systems such as directed infrared countermeasures (DIRCM). Experimental studies of laser beam propagation close to engine plumes provide knowledge and understanding for predicting and optimizing system performance. In this work multi wavelength laser beam propagation experiments were carried out close to a down-scaled jet engine exhaust. The experimental studied parameters included e.g. laser beam wander, intensity variations, temporal characteristics and phase distortions. In addition the experimental results were discussed in relations to applications such as DIRCM and active imaging. Ideas for improving modeling efforts of laser beam propagation in close vicinity of turbulent regions close to jet engine plume were considered.