Investigation of the Taylor-Culick flow through particle image velocimetry and numerical simulation

The Taylor--Culick flow corresponds to the flow injection through the lateral wall of a semi-infinite channel. This flow is intrinsically unstable downstream of a critical axial position. The flow disturbances develop in vortices that could couple with the acoustics of the channel, generating pressure oscillations. This is what occurs in large solid rocket motors in which the Taylor flow is induced by the propellant combustion. Depending mainly on the Reynolds number, three different flow regimes can be observed: laminar, transitional, or turbulent. The current paper presents an experimental and numerical investigation of that flow instability. The setup consists of a rectangular shape channel in which air is introduced through the bottom wall due to a porous plate. Quantitative measurements are performed with particle image velocimetry while unsteady numerical simulations are carried out using large eddy simulation. A special injection system for the seeding particles and a special arrangement for the laser sheet provide good quality particle image velocimetry data. The numerical simulations are validated against the particle image velocimetry results. They complete the particle image velocimetry investigation by following chronologically the instantaneous phenomenon. The experiments and the numerical simulations are performed at different injection velocities and channel heights. DOI: 10.2514/1.44616