A study of the intermittent region of a heated two dimensional plane jet

The conditioned velocity and temperature profiles in a plane jet of air were measured. The conditional point averages of the mean temperature and velocity, the shear stress, and the temperature-velocity correlation were found with respect to the moving interface for three intermittencies. The turbulent transport coefficients for heat and momentum were determined for the fully turbulent flow field at various axial stations. Using these conditional transport coefficients the turbulent Prandtl number was found to be essentially constant across the fully turbulent region of the jet. A model, based on constant transport coefficients, was proposed. The results confirms the value of the turbulent Prandtl number obtained from the experimental profiles. The velocity and temperature intermittencies were found at several axial stations. The intermittency profiles appear similar at different axial stations as do the frequencies of interface crossing. The point average temperature and velocity profiles show a coincidence at the interface with the temperature profile flatter than the velocity profile.