The asymmetric expansion and shock reflection characteristics in a suddenly expanding duct has been investigated. It is found that the symmetry breaking bifurcation characteristics depends on duct geometry. A novel Mach reflection to regular reflection shock transition has also been observed which depends only on the upstream pressure. 

The study deals with the fluid dynamics during the starting phase of a high altitude testing facility for rocket engines. It is found that the start-up process is governed by the dynamics of recirculation bubble seen in the diffuser. A bubble split-up process during the start-up results in a rapid vacuum pressure generation in the test chamber.

The reflection and refraction of a curved shock front as it propagates along an air-water interface has been investigated. It is found that the shock front transitions from a regular reflection to irregular reflection as the shock front propagates along the interface. A comparison of the shock wave transition conditions over the air water interface and over the solid surfaces has also been carried out.

The shock reflection characteristics over submerged submarine test body has been investigated using shadowgraph techniques. Underwater shock waves are produced using a shock tube places under water. The shadowgraph studies showed that the under water shock waves focusses at various locations over the submarine test body.