Direct numerical simulation (DNS) of turbulent flow and heat transfer has been performed over a heated wall-mounted cube positioned in a non-heated cube matrix by applying periodic boundary conditions in both streamwise (X) and spanwise (Y) directions. Three different channel heights namely, 3.4H, 2.0H, 1.5H corresponding to blockage ratio ($BR$) of 0.0735, 0.125 and 0.167 with H as the size of the cube are employed. The Reynolds number defined for the present simulation is kept at 3,854 (based on the cube height and average streamwise velocity) while the Prandtl number is chosen to be 0.712. A second-order spatial and temporal discretization has been used to solve the Navier-Stokes and energy equations. The flow structures and the associated heat transfer have been compared and discussed at different $BR$s based on the results of instantaneous snapshots and statistical quantities of flow variables. The turbulent states for each $BR$ has been compared using an anisotropic invariant map in the horseshoe vortex regime, top surface regime and in the wake regime. The total heat flux and turbulent heat flux quantities are compared near the cube’s surface to determine the contribution of both heat transfer by the thermal gradients, and due to the fluctuation induced heat flux. The overall Nusselt number is found to increase significantly with an increase in $BR$ from 0.0735 to 0.125. However, at $BR=0.167,$ no considerable augmentation in heat transfer has been observed as compared to $BR=0.125$. On the other hand, the friction factor increases monotonically but significantly with $BR$.

通过在流向（X）和跨度（Y）方向上应用周期性边界条件，已对位于非加热立方体矩阵中的加热壁挂立方体进行了湍流和传热的直接数值模拟（DNS）。三种不同的通道高度，分别为3.4H，2.0H，1.5H，对应于堵塞率（$乙\mathrm{[R}$使用0.0735、0.125和0.167的H）作为立方体的大小。为当前模拟定义的雷诺数保持在3,854（基于立方体高度和平均水流速度），而Prandtl数选择为0.712。二阶空间和时间离散化已用于求解Navier-Stokes和能量方程。在不同的位置对流动结构和相关的热传递进行了比较和讨论$乙\mathrm{[R}$基于瞬时快照的结果和流量变量的统计量。每个国家的动荡状态$乙\mathrm{[R}$已使用各向异性不变图在马蹄涡旋区，顶面区和尾流区进行了比较。在立方体表面附近比较总热通量和湍流热通量，以确定由热梯度引起的热传递以及由波动引起的热通量的贡献。发现总的Nusselt数会随着$乙\mathrm{[R}$从0.0735到0.125。但是，在$乙\mathrm{[R}=0.167，$ 与之相比，没有观察到明显的传热增加。 $乙\mathrm{[R}=0.125$。另一方面，摩擦系数单调增加，但随着$乙\mathrm{[R}$。