流体非线性碰撞研究初步——流体对喷

Preliminary Study of Fluid Nonlinear Dynamical Collide-Fluid Flow Interactions

为了分析通风空调领域大量存在的流体对抗或对喷等复杂非线性行为,了解流体复杂对流运动的机理,本文运用计算流体动力学方法模拟了室内等温层流气流、室内等温湍流气流及水箱内等温湍流水流等3种典型流体对喷实例。模拟结果发现,对于层流流体非线性碰撞,流体粘性在低雷诺数时起主要作用;对于湍流气流非线性碰撞,流体流速在全雷诺数范围及不同流动结构时都起主导作用;对于湍流水流非线性碰撞,流体粘性在低雷诺数时能起作用,而随着雷诺数增高及流动结构复杂化,流场则由流速及粘性等多种因素主导.由此研究可以看出,从控制参数、流体物性参数等影响流体对流运动的本质因素来探讨流体的非线性碰撞规律,可以为流场合理布局提供理论参数.

In order to analyze the fluid flow interaction or confrontation in ventilation and air-conditioning and the mechanism of complex fluid convection, we applied computational fluid dynamics (CFD) to simulate and analyze the following three typical fluid-flow interactions, namely, isothermal laminar indoor airflows, isothermal turbulent indoor airflows and isothermal turbulent water flows in water-tank. Simulation results showed that, for the nonlinear dynamical collision of laminar fluid flow, the fluid viscosity played a leading part when Reynolds number was low; for the nonlinear dynamical collision of turbulent airflow, the fluid velocity played a major part within Reynolds numbers and fluid flow structures; for the nonlinear dynamical collision of turbulent water flow, the fluid viscosity was an important factor when Reynolds number was low, and, the velocity and viscosity of fluid took effect together when Reynolds number increased and the flow structure became complex. This research provide theoretical parameters for the reasonable distribution of flow fields.