用CFD对间接蒸发冷却换热器的三维数值模拟

3D numerical simulation of indirect evaporative cooler by CFD method

应用计算流体力学(CFD)和数值传热学方法,对间接蒸发冷却器内流体流动与热质交换过程进行简化和假设,建立了换热器内三维层流流动与传热的数学物理模型.采用交错网格离散化非线性控制方程组,编制了三维SIMPLE算法程序.计算出间接蒸发冷却器内的速度场、温度场及浓度场,分析内部流动状态和热力分布.换热器通道间距改变时,计算所得压力梯度与实验测得的数据吻合得较好.这就能够为更加清楚地认识蒸发冷却换热器内复杂的换热机理,对这类换热器的优化设计提供必要的理论依据.

Adopting computational fluid dynamics （CFD） and numerical heat transfer method, threedimensional laminar flow and heat transfer mathematical and physical model were built by simplification and assumption on the indirect evaporative air cooler fluid flow and heat-mass exchange process. With the staggered grid discretization nonlinear governing equations, 3-D SIMPLE arithmetic program was programmed. And the flow field, temperature field and concentration field of the indirect evaporative air cooler were gained. Fluid flowing state and thermal distribution were analyzed. When the exchanger channel is changed, pressure gradient is well consistent with the experimental data. It provides some theoretical gist for the optimal design of the indirect evaporative air cooler.