• 충청수학회지
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• 제23권2호
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• pp.271-277
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• 2010

We prove the global (in time) vorticity existence for the 2-D Euler equations of a perfect incompressible fluid in $B^0_{{\infty},1}({\mathbb{R}}^2){\cap}L^p({\mathbb{R}}^2)$ with 1 < p < 2. Moreover, we prove that the particle trajectory map X(x, t) satisfies the following estimate: for some positive constant C $${\parallel}X^{\pm1}(\cdot,\;t)-id(\cdot){\parallel}_{B^1_{\infty,1}}{\leq}Ce^{e^{Ct}}$$, where id represents the identity map on ${\mathbb{R}}^2$.

• 태양에너지
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• 제2권1호
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• pp.9-16
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• 1982

The problem of transient laminar natural convection in compressible fluid in a rectangular enclosure is considered. The upper and lower boundaries of the enclosure are thermally insulating and the side boundaries are maintained at fixed temperatures. The fluid is considered to be a perfect gas with constant viscosity and thermal conductivity and the formulation differs from the boussinesq simplification in that the effects of variable density are completely retained. The motions are restricted to two dimensions. For incompressible fluid, the natural convection is driven mainly by buoyancy force. But the solutions show that for compressible fluid, the natural convection is driven by pressure and buoyancy forces and the thermally induced motion is acoustic in nature.