非Darcy多孔介质中的非线性对流

M·R·帕沙

doi:10.3879/j.issn.1000-0887.2010.05.004

非Darcy多孔介质中的非线性对流

doi: 10.3879/j.issn.1000-0887.2010.05.004

M·R·帕沙

马尔纳德工程学院数学系,哈桑-573201,卡纳塔克邦,印度

详细信息

中图分类号: O357.3
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出版历程
- 收稿日期: 1900-01-01
- 修回日期: 2010-02-19
- 刊出日期: 2010-05-15

Non-Linear Convection in a Non-Darcy Porous Medium

M. K. Partha

Department of Mathematics, Malnad College of Engineering, Hassan, Karnataka-573201, India

摘要

摘要: 利用温度-浓度-密度关系，研究非Darcy多孔介质中的自由对流问题．对于不同的惯性参数、传递参数、Rayleigh数、Lewis数、Soret数和Dufour数，分析了非线性温度参数和浓度参数对非线性对流的影响．浮力对对流起着辅助的附加作用，当惯性作用不计时，切向速度随着非线性温度和浓度的增加而急剧地增加．然而，当惯性效应不为0时，非线性温度和浓度对切向速度的影响是有限的．对两个传递参数、惯性影响参数以及控制非线性温度和浓度的其他参数，取不同的数值时，浓度分布有点儿变化，并在不同的范围内传播．随着非线性温度和浓度的增加，传热／传质在很大的范围内变化，这取决于是Dacry多孔介质，还是非Darcy多孔介质．当所有的影响（惯性的影响、两个传递系数的影响、Soret和Dufour的影响）同时为0/不为0，在非线性温度／浓度参数以及浮力的共同作用下，分析了传热／传质的变化．发现在Darcy多孔介质中，温度和浓度以及它们的交叉扩散，对传热／传质的影响，要比非Darcy多孔介质要大．发现了浮力的负面作用，随着非线性温度系数的增加，传热／传质率是提高的，而随着非线性浓度系数的增加，传热／传质率是下降的．
- 非Darcy多孔介质 /
- 自由对流 /
- 温度传递 /
- 溶质传递
Abstract: Natural convection in a non-Darcy porous medium was studied using the temperature-concentration-dependent density relation. The effect of two parameters a₁ and a₂ responsible for non-linear convection was analyzed for different values of inertial parameter, dispersion parameters, Rayleigh number, Lew is number, So retnumber and Dufour number. In the aiding buoyancy, tangential velocity f' increases steeply with an in crease in the parameters of non-linear temperature and concentration (a₂ & a₁), when the inertial effect is zero. But, when it is non-zero, the effect of a₂ or a₁ on f' is marginal. The concen tration distribution varies appreciably and spreads in different ranges for different values of double dispersion parameters, inertial effect parameter and also for parameters which control non-linear temperature and concentration. Heat and masstrans fervary extensively with an increase in a₁ and a₂ depending on Dacry and non-Darcy porous medium. Variation in heat and masstrans fer when all the effects (inertial effect, double dispersion effects and Soret and Dufour effects) are smiultan eously zero and non-zero and com bined effect of param eters of non-linear temperature and concentration and Buoyancy are analyzed. The effect of a₁ and a₂ and also the cross diffusion effects on heat and masstran sferare observed to be more in Darcy porous medium com pared to non-Darcy porous medium. In the opposing buoyancy, it is observed that the effect of a₁ is to in crease the heat and masstran sferrate, whereas that of a₂ is to decrease.
- non-Darcy porous medium /
- natural convection /
- double dispersion /

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