Test Arrangement and Results

The jet flow is issued from the Jet/Counter-current facility at the Fluid Mechanics Research Laboratory at Florida State University (Fig. 1.2). To make the PIV measurement, the flame is seeded with 

The velocity field for a single realization presented in the reference frame moving with the convective velocity of the vortices is shown in Fig. 1.4. The vorticity distribution vividly depicts the vortex ring signature. This signature is also put in evidence in Fig. 1.5. This figure shows the Speckle displacement field superposed to the temperature. 

The temperature is obtained by converting the refractive index values using the Gladstone-Dale law. The underlying assumption is that the behavior of the gas mixture can be well approximated by ideal gas. The temperature estimate is well within the expected range as the adiabatic flame temperature for a propane-air mixture flame is 1977 C. This is the maximum temperature that a propane-air flame can reach under atmospheric pressure and for = 1. 

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