基于FLOW-3D的田间便携式短喉槽水力性能数值模拟  

Numerical simulation of hydraulic performance for portable short-throat flume in field based on FLOW-3D

作　　者：肖苡辀 王文娥[1] 胡笑涛[1] 

机构地区：[1]西北农林科技大学水利与建筑工程学院,杨凌712100

出　　处：《农业工程学报》2016年第3期55-61,共7页Transactions of the Chinese Society of Agricultural Engineering

基　　金：公益性行业(农业)科研专项(201503125);国家自然科学基金项目(51179163);国家"十二五"科技支撑计划项目(2011BAD29B01)

摘　　要：田间量水是实现灌区计划用水和节水农业的关键技术,但由于试验条件、测量方法和精度的限制,传统的水工模型试验分析田间量水设施的水力性能存在一定局限性。该文基于FLOW-3D软件,采用RNG k-ε三维湍流模型、Tru VOF方法、FAVOR(fractional area volume obstacle representation)技术模拟喉口宽度为51 mm的田间便携式短喉槽过槽水流的三维流场。与试验结果对比表明:过流能力、水流流态以及水深与试验结果较为吻合,误差小于10%,采用的数值模拟方法能够有效地模拟田间便携式短喉槽水力性能,在确定数值模拟可靠性的前提下,对其水力性能进行分析。数值模拟结果显示:佛汝德数、流速在自由出流工况下沿程增大,在淹没出流条件下先增大后减小,并由佛汝德数分析结果确定了临界水深断面所在区域为喉口段后半部分;通过回归分析得到的田间便携式短喉槽上游水深与流量计算公式最大测流误差为-5.63%,满足灌区量水精度的要求;该量水槽最大水头损失占总水头的12.10%,相比于长喉道量水槽的13%较小。该研究对提高量水设备研发效率、降低研发成本与周期、促进中国灌区流量精准测量设备的推广具有实用价值。Improvement of water management can encourage conservation and make best use of our limited water resources. The measurement of flow rates is an important element of water management. Many devices and structure have been developed for the measuring discharge but measuring flume is one of the most accepted and used structure. According to the practical situation Of irrigated areas in northern China, use of portable short-throat flume in field to measure the discharge of water inlet in the field is an emerging technique developed for water discharge measurement of inlet in the field, which contributes to control of irrigation water consumption and water conservation. Based on FLOW-3D software in this study, RNG k-c three-dimensional turbulence model, TruVOF technique and FAVOR （fractional area volume obstacle representation） method were employed to simulate three-dimension flow field in portable short-throat flume in field with a 51 mm width throat under 18 working conditions. Experimental results about portable short-throat flume in field were also obtained based on a new test to validate the simulation results. It verified discharge capacity of the flume. The parameter settings and boundary conditions used in the CFD models provided an efficient approach for simulation of the flow through portable short-throat flume in field. Combined with hydraulic experiments, hydraulic performance was obtained from simulation analyses on water surface profiles, Froude number, velocity distribution and head loss. Comparison between experiments and simulations showed that measured and simulated flow capacity, flow field and flow depth have a good consistency, and relative errors were less than 10%, and gave a solid agreement between experimental and numerical simulation results, Hence, it can be used to simulate flow state of portable short-throat flume in field effectively and visually. On the basis of reliable numerical simulated consequents, analyses of hydraulic performances in detail were carried out. The simulation res

关 键 词：水工建筑物 佛汝德数 流速 水头损失 便携式短喉槽 数值模拟 

分 类 号：S274.4[农业科学—农业水土工程]