ABSTRAKT

An experimental study is conducted on mixing phenomena inside a circular cavity at the intersection of two crossing ducts, creating converging and diverging flow into and out of the cavity after mixing. The intersecting angle and the relative flow rates in the pair are varied to investigate their effects on the secondary flow and mixing phenomena in the cavity. Flow pattern is visualized by means of the particle tracing method and velocity distribution is obtained by laser Doppler velocimetry (LDV). The exiting flow rate and total pressure loss across the cavity are determined by hydrometry. Colorimetry, which has been used with color video images to analyze the visual field of complex scenes, such as landscapes and building interiors, is employed to investigate the mixing phenomena. It is shown that a critical Reynolds number exists beyond which the mixing performance and total pressure loss across a cavity becomes independent of the intersecting angle and relative converging flow rate.