柱体绕流的CIP方法模拟

Numerical simulation of flow past a cylinder using a CIP-based model

柱体绕流和流致振动现象是一个复杂的工程问题,利用自主研发的CIP-ZJU模型,对低雷诺数(Re<300)圆柱和方柱绕流问题开展了数值模拟。模型在直角坐标系统下建立,采用紧致插值曲线CIP方法作为流场的基本求解器离散了Navier-Stokes方程,基于多相流的理论实现流-固耦合同步求解,利用浸入边界方法处理固体边界。模拟结果与文献结果进行比较,二者吻合情况较好。通过引入压力阻力项和摩擦阻力项,分析了Strouhal数、阻力系数、升力系数等参数随雷诺数的变化情况。结果表明,圆柱绕流与方柱绕流在水动力参数的变化规律上存在多处差异。

Flow past a cylinder and the flow-induced vibration phenomenon are complex engineering problems. We developed a CIP-ZJU（ constrained interpolation profile-Zhejiang University） model to study the flow past circular and square cylinders for Reynolds numbers Re 300. The model was established in the Cartesian coordinate system,using the CIP method as the base flow solver to discretise the Navier-Stokes equations. The fluid-structure interaction was treated as multiphase flow,with liquid and solid phases solved simultaneously. We used an immersed boundary method to deal with the boundary of the solid body. We then compared our computations with available results and obtained good agreements. By introducing pressure and viscous drags,we analyzed the variations in the Strouhal number,drag coefficient,and lift coefficient with the Reynolds numbers. Results show that the variations of the dynamic characteristics differ between the flows past circular and square cylinders.