Purpose

This study aims to illustrate the impacts of the motion of circular cylinders on the natural convection flow from variable heated partitions inside the X-shaped cavity filled with Al₂O₃-water nanofluid. A partial layer of a homogeneous/heterogeneous porous medium is located in the top area of the X-shaped cavity.

Design/methodology/approach

Three different cases of the porous media including homogeneous, horizontal heterogeneous and vertical heterogeneous porous media were considered. Three different thermal conditions of the embedded circular cylinders including hot, cold and adiabatic conditions are investigated. An incompressible scheme of smoothed particle hydrodynamics (ISPH) method is modified to compute the non-linear partial differential equations of the current problem. Two variable lengths of the left and right sides of the X-shaped cavity have a high-temperature T_h and a low-temperature T_c, respectively. The other wall parts are adiabatic. The numerical simulations are elucidating the dependence of the heat transfer and fluid flow characteristics on lengths of hot/cold source L_h, porous cases, Darcy parameter, thermal conditions of the embedded circular cylinders and solid volume fraction.

Findings

Overall, an increment in length of hot/cold source leads to augmentation on the temperature distributions and flow intensity inside the X-shaped cavity. The hot thermal condition of the circular cylinder augments the temperature distributions. The homogeneous porous medium slows down the flow speed in the top porous layer of the X-shaped cavity. The average Nusselt number decreases as L_h increases.

Originality/value

ISPH method simulated the motion of circular cylinders in the X-shaped cavity. The X-shaped cavity is saturated with a partial layer porous medium. It is found that an increase in hot source length augments the temperature and fluid flow. ISPH method can easily handle the motion of cylinders in the X-shaped cavity. Different thermal conditions of cylinders can change the temperature distributions in X-cavity.

中文翻译：

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使用ISPH方法在充满纳米流体的X形腔中自然对流流动过程中圆柱的运动

目的

这项研究旨在说明圆柱运动对X形腔内充满Al ₂ O _3-水纳米流体的可变加热隔板产生的自然对流的影响。均质/非均质多孔介质的部分层位于X形腔的顶部区域。

设计/方法/方法

考虑了多孔介质的三种不同情况，包括均质，水平异质和垂直异质多孔介质。研究了嵌入式圆柱体的三种不同热条件，包括热，冷和绝热条件。修改了光滑粒子流体动力学（ISPH）方法的不可压缩方案，以计算当前问题的非线性偏微分方程。X形腔的左侧和右侧的两个可变长度分别具有高温T _h和低温T _c。其他壁部分是绝热的。数值模拟阐明了传热和流体流动特性对热/冷源长度的依赖性。L _h，多孔情况，达西参数，嵌入式圆柱体的热工况和固体体积分数。

发现

总体而言，热/冷源长度的增加导致X形腔内部的温度分布和流动强度增加。圆柱体的热热条件增加了温度分布。均匀的多孔介质会减慢X形腔顶部多孔层中的流速。随着L _h增加，平均努塞尔数减少。

创意/价值

ISPH方法模拟了X形腔中圆柱的运动。X形腔充满了部分层多孔介质。发现热源长度的增加会增加温度和流体流量。ISPH方法可以轻松处理X形腔中圆柱体的运动。气缸的不同热条件会改变X型腔中的温度分布。