Laser Doppler Velocimetry (LDV) measurements are presented
for a nominally two-dimensional constant-density flow over a
surface-mounted triangular cylinder. The thickness of the boundary
layer approaching the triangular cylinder is much less than the
height of the triangle. Momentum and turbulent kinetic energy
balances are presented and comparisons are made with other separated
and reattaching flows. Also, time domain information is presented in
the form of autocorrelations and spectra. From the energy balances,
the importance of the pressure transport term at the high-speed edge
of the shear layer is seen. Observations of the relationships between
the shapes of the spectra and the details of the energy balance are
made. For example, the slope of the velocity spectra varies from the
free-stream value of −5/3 to a value of −1 in the
middle of the recirculation region. Concurrent with this increase in
slope is a decrease in the role of shear production in the turbulent
kinetic energy balance and an increase in the role of advection and
turbulent transport. From the two-component LDV measurements, a very
low-frequency unsteadiness is shown to contribute energy
preferentially to different components of the velocity fluctuations
depending on the location in the flow.
Measurement of various terms in the turbulent kinetic energy balance within a flame and comparison with theory
