Experimental Investigation of Recessed Wall Flameholder

Abstract

Flameholders are of great importance in the design of ramjet combustors. It was already confirmed by L.H. Huellmantel et al. that recessed wall flameholders had the advantages of smaller pressure drop and wider range of flame stabilization compared with bluff body flameholders. This paper presents experimental investigations of more detailed characteristics of recessed wall flameholders as the preliminary sudy of their application for practical use. First, it is shown through flame photographs that the flame-holding mechanism of the recirculation flow in the groove of a recessed wall flameholder is similar to that of bluff body flameholders. Second, from the experimental results on the influence of the groove width upon the flame stability limits, it is found that the condition l/h=5 is the best for the flame stabilization, where l and h denote the width and the depth of the groove respectively.