An aerospike nozzle has been expected as a candidate for an engine of a reusable space shuttle to respond to growing demand for rocket-launching and its cost reduction. In this study, flow field structures in any cross sections around a clustered linear-type aerospike nozzle are visualized and analyzed, using laser induced fluorescence (LIF) of NO seeded in the carrier gas N₂. Since the flow field structures are affected mainly by pressure ratio (P_s /P_a), the nozzle is set inside a vacuum chamber to carry out the experiments in the wide range of pressure ratios from 75 to 200. The flow fields are visualized in several cross-sections, demonstrating the complicated three-dimensional flow field structures. The pressure sensitive paint (PSP) of PtTFPP bound by poly-IBM-co-TFEM is also applied successfully to measurement of the complicated pressure distribution on the nozzle surface. The pressure distribution on the base surface of the nozzle is measured to analyze thrust compensation of truncated aerospike nozzles.

View full abstract