New developments in laser-induced photochemical anemometry (LIPA)

摘要

Abstract: This paper introduces advances in LIPA (Laser Induced Photochemical Anemometry) and LIPA's application to the induction flow of a four-stroke internal combustion (IC) engine employing these advances. The IC engine is represented by a one-valve axisymmetric water analog model which was manufactured from quartz in order to achieve complete visual access since LIPA is an optical measurement concept. Two flow visualization techniques are used to obtain a qualitative picture of the induction flow. Reduction of LIPA data is done for the realization of the intake flow of one engine cycle at 20 RPM of obtain quantitative information of the flow field - velocity and vorticity maps for several crank-angles during the early phase of intake will be presented. These results which characterize the flow field in terms of fluid dynamic quantities are compared to the those results attained by flow visualization. A strong correlation between the two data sets (visualization and LIPA) will be denoted.!12