Effect of Initial Conditions on the Scalar Decay in Grid Turbulence at Low Rλ
نویسندگان
چکیده
Abstract Decaying grid turbulence is considered at low Reynolds number (Rλ ~ 50) for different initial conditions. Three different grid geometries are used. Heat is injected via a mandoline at a distance of 1.5 M from the grid. The amount of heating is such that temperature may be treated as a passive scalar. A small contraction (1.36:1) is added at a distance of 11M downstream of the grid. The power-law exponents for the scalar variance are compared with those for the turbulent kinetic energy. These exponents depend on the grid geometry.
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