Energy dissipation in body-forced plane shear flow
نویسندگان
چکیده
منابع مشابه
Energy dissipation in body - forced plane shear flow
We study the problem of body-force driven shear flows in a plane channel of width ℓ with free-slip boundaries. A mini-max variational problem for upper bounds on the bulk time averaged energy dissipation rate ǫ is derived from the incompressible Navier-Stokes equations with no secondary assumptions. This produces rigorous limits on the power consumption that are valid for laminar or turbulent s...
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The total dissipation rate for magnetohydrodynamic (MHD) flows in plane geometry with both velocity and magnetic shear is studied. For some boundary conditions it is shown that the lower bound on the dissipation rate is achieved by the equivalent of Stokes flow for MHD. Using the ‘background method’ (Doering & Constantin, Phys. Rev. Lett. 69, 1648–1651 (1992)) upper bounds for the dissipation r...
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ژورنال
عنوان ژورنال: Journal of Fluid Mechanics
سال: 2003
ISSN: 0022-1120,1469-7645
DOI: 10.1017/s002211200300613x