阻尼网特性数值模拟

丛成华; 廖达雄

doi:10.13700/j.bh.1001-5965.2014.0018

阻尼网特性数值模拟

doi: 10.13700/j.bh.1001-5965.2014.0018

丛成华^1,2,
廖达雄¹

1.
中国空气动力研究与发展中心空气动力学国家重点试验室, 绵阳 621000
2. 中国空气动力研究与发展中心设备设计及测试技术研究所, 绵阳 621000

基金项目: 空气动力学国家重点实验室基金资助项目(SKLA-JBKY11040401)

详细信息

作者简介:
丛成华(1979-),男,山东泰安人,副研究员, cch_sd@163.com.

中图分类号: V211.3
计量
- 文章访问数: 1320
- HTML全文浏览量: 227
- PDF下载量: 773
- 被引次数: 0
出版历程
- 收稿日期: 2014-01-07
- 网络出版日期: 2014-12-20

Numerical investigation about field characteristics of screen

Cong Chenghua^1,2,
Liao Daxiong¹

1.
State Key Laboratory of Aerodynamics, China Aerodynamics Research and Development Center, Mianyang 621000, China
2. Facility Design and Instrumentation Institute, China Aerodynamics Research and Development Center, Mianyang 621000, China

摘要

摘要: 依靠经验公式和工程估算等传统方法,无法对阻尼网性能进行精确评估.为确定阻尼网压力损失系数和降湍性能,采用计算流体力学方法,结合适当的边界条件,对阻尼网进行了模拟.使用数值模拟能够得到不同开孔率阻尼网在不同雷诺数、不同入射方向、不同目数的损失系数,与试验结果更为接近,在30°~45°大角度入射时得到的损失系数更为精确;在入射气流与阻尼网平面呈一定夹角时,阻尼网后的气流压力和速度呈现脉动趋势,传播距离大约为100d;在雷诺数小于40时流动保持层流状态,扰动传播距离为50d,此时降湍效果最好,随雷诺数增加,扰动传播距离增加至400d;在流动未失稳时,开孔率越低,降湍效果越明显,开孔率低于0.5时流动容易失稳;开孔率保持不变,随目数增加阻尼网损失系数增加明显,降湍能力提升.因此可以根据数值模拟结果选择阻尼网的最优参数.
- 阻尼网 /
- 流动控制 /
- 开孔率 /
- 损失系数 /
- 湍流强度 /
- 数值模拟
Abstract: There is no reasonable path to evaluate screen performance accurately based on conventional method, such as the experiential formula and engineering correlations technology. Computational fluid dynamics (CFD) with proper boundary conditions was used to find screen performance of different parameters including total pressure loss coefficient and control ability of turbulence intensity. Total pressure loss coefficient of the screen was obtained precisely using CFD with different open area ratio, Renault number, incidence angle, wires per inch, etc., especially, incidence angle equal to 30°-45°. Pressure and velocity after screen was pulsant when air flowed into the screen at certain incidence angle, and the disturbance would become weak after about 100d. The flow regime around the screen kept laminar when Re less than 40, the distance of disturbance about 50d, and that turbulence intensity was reduced on a large scale. With the increase of Re, the distance of disturbance increased to about 400d, the reduce factor of turbulence intensity became smaller than laminar regime significantly. Smaller is the open area ratio of screen before flow regime changed to instability state, bigger is reduce factor of turbulence intensity. Based on the details of numerical results, the instability most likely appears when openning to sectional area ratio less than 0.5. Total pressure loss coefficient and reduce factor of turbulence intensity increases at distinct rate with increase of wires per inch when open area ratio keeps constant. It is concluded that the optimal parameters of the screen can be obtained based on numerical results.
- screen /
- flow control /
- open area ratio /
- total pressure loss coefficient /
- turbulence intensity /
- numerical simulation

HTML全文

参考文献(25)

[1]	Teitel M.On the applicability of the forchheimer equation in simulating flow through woven screens[J].Biosystems Engineering,2011,109:130-139
[2]	Schubauer G B.Aeodynamic characteristics of damping screens[R].NACA-TN-2001,1950
[3]	Baines W D,Petersen E G.An investigation of flow through screens[J].Transactions of ASME,1951,73:467-480
[4]	Mehta R D.Turbulent boundary layer perturbed by a screen[J].AIAA Journal,1985,23(9):1335-1342
[5]	Mehta R D.Boundary layer two-dimensionality in wind tunnels[J].Experiments in Fluids,1987,5:358-360
[6]	Dadone A,Napolitano M.Pressure losses through screens[R].NASA-PUBL-146,1974
[7]	Nevelsteen K.Screen characterization under fan induced swirl conditions[J].IEEE Transactions on Components and Packaging Technology,2006,29(2):385-394
[8]	Livesey J L,Laws E M.Simulation of velocity profiles by shaped gauze screens[J].AIAA Journal,1973,11(2):184-188
[9]	Laws E M,Livesey J L.Flow through screens[J].Annual Review of Fluid Mechanics,1978,10:247-266
[10]	Groth J,Johansson A V.Turbulence reduction by screens[J].Journal Fluids Mechanics,1988,197:139-155
[11]	Derbunovich G I,Zemskaya A S.Optimum conditions of turbulence reduction with screens[J].Fluid Dynamics,1993,28(1):138-144
[12]	Sahin B.The pressure drop and flow characteristics of wide-angle screened diffusers of large area ratio[J].Journal of Wind Engineering and Industrial Aerodynamics,1995,58:33-50
[13]	Hancock P E.Plane multiple screens in non-uniform flow with particular application to wind tunnel settling chamber[J].European Journal Mechanics B Fluids,1998,17(3):357-369
[14]	Kulkarni V.Simulation of honeycomb-screen combinations for turbulence management in a subsonic wind tunnel[J].Journal of Wind Engineering and Industrial Aerodynamics,2011,99:37-45
[15]	康钦军.圆柱绕流的数值模拟[D].北京:清华大学,1999 Kang Qinjun.Numerical simulation around a circular cylinder[D].Beijing:Tsinghua University,1999(in Chinese)
[16]	Abid R.Evaluation of two-equation turbulence models for predicting transitional flows[J].International Journal of Engineering Science,1993,31:831-840
[17]	Grumet A A.Navier-stokes analysis of NWTC back leg diffuser[R].AIAA-97-0094,1997
[18]	Aljabari S.Prediction of the pressure loss coefficient of wind tunnel turbulence reducing screens[R].AIAA-92-4043,1992
[19]	Perry R H.Perry's chemical engineers'handbook[M].6th ed.New York:McGraw-Hill Press,1984:23-24
[20]	Wieghardt K F G.On the resistance of screens[J].Aeronautial Quarterly,1953,4:186-192
[21]	Idelchik I E.Handbook of hydraulic resistance[M].3rd ed.Boca Raton:CRC Press Inc,1994:359-361
[22]	Brundrett E.Prediction of pressure drop for incompressible flow through screens[J].Journal of Fluids Engineering,1993,115(2):239-242
[23]	伍荣林,王振羽.风洞设计原理[M].北京:北京航空学院出版社,1985:47-49 Wu Ronglin,Wang Zhenyu.Wind tunnel design method[M].Beijing:Beijing Aeronautics Institute Press,1985:47-49(in Chinese)
[24]	Scheiman J.Comparison of experimental and theoretical turbulence reduction from screens,honeycomb and honeycomb-screen combinations[J].Journal of Aircraft,1981,18(8):638-643
[25]	Scheiman J.Considerations for the installation of honeycomb and screens to reduce wind-tunnel turbulence[R].NASA-TM-81868,1981