测控一体化闸门闸前流态与测量准确度试验研究

Experimental study of the accuracy of integrated monitoring and control gate and the water flow in front of the gate

【目的】探究进水口流态变化对箱涵式测控一体化闸门测量准确度的影响规律。【方法】以灌区常用规格600mm×600 mm测流箱为试验对象,在室内试验基地布设扰动设施开展了98组模型试验,研究水流对称性、闸门开度、水位变化对闸前流态、设备测量准确度的影响。【结果】(1)不同工况下测流箱前漩涡的强度、发生频率、持续时间各不相同;当测流箱为非淹没状态,漩涡多为表面凹陷涡,对测量准确度影响不显著;当测流箱为淹没状态时,且淹没水深>20 cm后,漩涡强度随淹没深度增加而减弱,当淹没深度<20 cm时,漩涡强度最大,出现贯通式漩涡强度频率明显增大,此时设备测量误差显著增大;(2)进水口流态的对称性是影响漩涡产生的主要因素之一,当进水口流态为非对称流时,测流箱内极易出现吸气漩涡,测量误差显著增大,最大误差约为22.58%。【结论】调整测箱淹没深度、闸门开度、进水口水流对称性等因素,可有效降低测流箱周围漩涡强度,提升设备测量准确度。

【Objective】This paper is to investigate how changes in flow pattern at the water inlet influence the measurement accuracy of box-type integrated measurement and control gates and water flow in front of the gate.【Method】Using a commonly used 600 mm×600 mm flow measurement box in irrigation systems as the test subject,98 model tests were conducted at an indoor testing facility.Disturbance facilities were set up to study the effects of flow symmetry,gate opening,and water level changes on the flow pattern and measurement accuracy in front of the gate.【Result】①The intensity,frequency,and duration of vortices in the flow measurement box vary across different operating conditions.When the measurement box is non-submerged,surface depression vortices are predominant,with minimal impact on measurement accuracy.When the box is submerged and water depth exceeds 20 cm,vortex intensity decreases with increased submergence,but when the depth is less than 20 cm,vortex intensity reaches a maximum,and through-vortices form,causing a significant increase in measurement error.②The symmetry of the inlet flow pattern is a primary factor influencing vortex formation.Under asymmetric inlet flow conditions,suction vortices are likely to occur in the measurement box,significantly increasing measurement error,with a maximum error of about 22.58%.【Conclusion】Adjusting submergence depth,gate opening,and inlet flow symmetry effectively reduces vortex intensity around the measurement box and improves measurement accuracy.