Characterisation of Turbulence using Particle Image Velocimetry and the Measurement of Burn Rates

The project involves developing particle image velocimetry PIV, as a practical way of characterising gaseous turbulence. It involves seeding the gas with small particles of olive oil in an aerosol of very limited concentration. The turbulence is designed to be isotropic, in the central region of a fan-stirred pressure vessel, equipped with four windows for optical access. Initially, the characterisation will involve velocity and length scale measurement in non-reacting gases.

This will be allied to studies of reacting gases and the measurement of propagating flame velocities. flows. The propagation rate of the flame is governed by the ratio of chemical to eddy lifetime, expressed as a Karlovitz stretch factor.  Fast combustion is required for efficiency but too high a velocity can create shock waves followed by autoignition and damaging knock. The ultimate aim is controlled, efficient combustion with minimal pollution.