AN OPTICAL METHOD FOR LOCAL EQUIVALENCE RATIO MEASUREMENTS APPLIED TO HYDRAULIC SIMULATION OF A RAMJET COMBUSTION CHAMBER

摘要

Hydraulic simulation is a very useful tool to predict global performances of ramjet combustion chambers. Optical techniques can give a lot of information concerning the structure of the flow. In the special case of combustion chambers, it is possible to obtain a spatial repartition of local equivalence ratio and to predict combustion efficiency. This paper presents a ramjet research chamber with two lateral inlets specifically designed for being installed on a hydraulic test rig in order to obtain an experimental database for validating numerical codes. Visualizations are presented and an optical method using laser tomography, LIF and digital acquisition and processing is developed. Experimental procedures are detailed and results concerning local air and fuel flow rates, and local equivalence ratios or mixture fuel/air ratios are analyzed. In addition, an ONERA 's CFD code is presented and the calculated results are compared with experimental data with a rather good agreement.