xperiments on a Solid Rocket Engine

We performed the first Particle-Image Velocimetry (PIV) measurements on a small Solid Rocket Engine to measure velocities in excess of 600m/s in a flow whose temperature exceeded 3000K. These measurements were complicated by the extreme luminescence of the rocket exhaust, the lack of control over the seeding, and the corrosive environment (see figure).

Several techniques were used to break this problem. For example, a liquid crystal shutter driven by custom electronics was used to reduce the light entering the camera from the luminous exhaust. A test rig was built to measure the the thrust and fuel consumption of the engine through the various phases of its burn time. These experiments on the Estes C6-0 rockets yielded an unique dataset containing both macroscopic (thrust, fuel consumption) and microscopic (velocity field) data, the combination of which is hard to find for rocket engines. Such measurements are useful for the validation of full-system simulations like those done at the Center for Simulation of Advanced Rockets at Urbana-Champaign.

Most interestingly, the axial mean velocity profiles exhibited self-similarity within the regions investigated despite the compressible, non-isothermal, multiphase nature of the flow. Does this mean that multiphase flows of a certain nature exhibit self-similarity?

Read more about this project in the publication Particle-image velocimetry measurement in the exhaust of a solid rocket motor, Experiments in Fluids, Volume 36, page 166-175.