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搖臂式噴頭內(nèi)流道流場(chǎng)數(shù)值模擬
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國(guó)家自然科學(xué)基金資助項(xiàng)目（51079140）;西北農(nóng)林科技大學(xué)基本科研業(yè)務(wù)費(fèi)資助項(xiàng)目（Z109021008）


Investigations on Internal Flow Characteristics of Impact Sprinkler Based on Numerical Simulation Method
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    摘要:

    用Pro/E軟件建立噴頭內(nèi)流道的三維實(shí)體模型，選擇RNG k—ε模型在CFD軟件Fluent中模擬了雨鳥30PSH型搖臂式噴頭在10種入口壓力和4種主噴嘴直徑組合下的內(nèi)流道流場(chǎng)，分析了噴頭主副噴嘴的流量、入口壓力與出口平均速度等參數(shù)的關(guān)系。研究結(jié)果表明：主噴嘴直徑增大時(shí)，副噴嘴流量幾乎不變；主、副噴嘴的流量分配比例由主噴嘴直徑?jīng)Q定，與入口壓力無(wú)關(guān)。入口壓力增大，主噴嘴出口平均速度增大，但副噴嘴出口平均速度不變。噴頭主、副噴嘴的平均湍動(dòng)能隨入口壓力增大而增大，不受主噴嘴直徑變化的影響。主噴嘴出口靜壓力、湍動(dòng)能和速度的標(biāo)準(zhǔn)差、副噴嘴出口靜壓力標(biāo)準(zhǔn)差與入口壓力近似成正比；而副噴嘴出口湍動(dòng)能和速度的標(biāo)準(zhǔn)差隨主噴嘴直徑或入口壓力增大產(chǎn)生較大的無(wú)規(guī)律變化。噴頭內(nèi)流道流場(chǎng)的可視化結(jié)果顯示噴頭副噴嘴與彎管連接處?kù)o壓力較大，接近噴頭入口靜壓力。

    Abstract:

    The geometric model of internal runner was constructed in Pro/E software.The internal flow field of the Rain Bird 30PSH impact sprinkler was conducted by using computational fluid dynamics (CFD) software Fluent with RNG k—εmodel at ten different pressure values and four types of range nozzle. Relationship between flow rate, inlet pressure and average velocity of outlet of range and spreader nozzle were evaluated. The results showed the flow rate of spreader nozzle was almost the same regardless of shifting the diameter of range nozzle. The distribution between range and spreader nozzle depended on the diameter of range nozzle was independent with inlet pressure. The average velocity magnitude of the range nozzle increased with the increasing of inlet pressure but spreader nozzle would not. The turbulent kinetic energy of range and spreader increased with the increasing of inlet pressure was independent with nozzle size. The standard deviation of static pressure, turbulent kinetic energy, velocity of range nozzle and static pressure of spreader nozzle were almost in direct proportion to inlet pressure. Biggish and irregular changing was happened to standard deviation of turbulent kinetic energy and velocity of spreader nozzle. Flow field visualization indicated that joint of runner and spreader nozzle had maximal static pressure. 

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韓文霆,Nguyen Van Lanh,徐琳.搖臂式噴頭內(nèi)流道流場(chǎng)數(shù)值模擬[J].農(nóng)業(yè)機(jī)械學(xué)報(bào),2011,42(8):58-64. Han Wenting, Nguyen Van Lanh, Xu Lin. Investigations on Internal Flow Characteristics of Impact Sprinkler Based on Numerical Simulation Method[J]. Transactions of the Chinese Society for Agricultural Machinery,2011,42(8):58-64.

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