何楓++姚朝暉++張錫文++劉正先

摘 要：對Re數(shù)不高的熱對流流場，目前流場CFD數(shù)值模擬策略主要采用大渦模擬和時均湍流模式兩種方法。在進(jìn)行大渦數(shù)值模擬時，其中亞格子模式分別采用Smagorinsky-Lilly模式、壁面自適應(yīng)當(dāng)?shù)販u粘模式、Smagorinsky-Lilly動力亞格子模式、Vreman的亞格子模式，主要對比各種亞格子模式在計算熱對流時的優(yōu)勢和差異。進(jìn)行時均湍流模式數(shù)值模擬時，采用各種湍流模式，對比計算差異，并與LES對比，確定對熱對流湍流信息的抑制程度，為今后改進(jìn)湍流模式奠定基礎(chǔ)。在熱對流的數(shù)值模擬中，網(wǎng)格技術(shù)也是關(guān)鍵，采用根據(jù)初算結(jié)果，調(diào)整網(wǎng)格密度分布技術(shù)，加快計算收斂。根據(jù)檢測固定點參數(shù)的變化以及熱通量平衡狀態(tài)，判定計算是否收斂。實驗分別采用激光粒子測速、熱線進(jìn)行速度測量，采用熱電偶測量溫度，校正CFD計算結(jié)果。

關(guān)鍵詞：熱對流 湍流 數(shù)值模擬

Progress Report of 2012

He Feng1 Yao Chaohui1 Zhang Xiwen1 Liu Zhengxian2

（1.Tsinghua University； 2.Tianjin University）

Abstract：Currently，the solution strategies for not high Re number convection is large eddy simulation method and RANS with turbulent models method. For the LES method， various sub-grid scale models are used， such as Smagorinsky- Lilly model， Lillys dynamic Smagorinsky model Vremans model and wall-adapting local eddy-viscosity model， to compare the difference and the applicability for convection flow field. The simulation data with the turbulent models are compared with the experimental data and LES data in order to determine that how much turbulent information is restrained by the method of turbulent models. Grid technique also play key role for simulation convergence. Adjusting grid density and monitoring surface variables and the balance of the heat transfer flux can help to reach the simulation convergence. Some related experiments are done by the particle image velocimetry （PIV） and hot wire technology.

Key Words：Convective flow； Turbulence； Numerical simulation