CAJ | 학술논문

针对水工物理模型试验中尚无简单易行的表面流速测量方法,提出了一种新型光电非接触式表面流速直接测量法.在对光束入射水体后散射光强度公式进行推导的基础上,根据水体浅层泥沙浓度的统计继承效应,得出了经上下游浅层泥沙调制的散射光强成相关特性的结论.根据上下游散射光的相关特性,推导了流速测量公式,并分析了上下游测量间距、水流流速、采样率对测量结果的影响.搭建了实验系统,在6种不同标定流速下,分析了不同含沙量对测量精度的影响.实验结果表明,在0～50 kg/m~3 6种不同含沙量情况下,实测流速与标定流速的一致性均较好,但水体在10～50 kg/m~3适量含沙情况下,测量精度较不含沙情况有所提高,测量绝对误差均小于0.1 m/s,相对误差能控制在8%以内.
침대수공물리모형시험중상무간단역행적표면류속측량방법,제출료일충신형광전비접촉식표면류속직접측량법.재대광속입사수체후산사광강도공식진행추도적기출상,근거수체천층니사농도적통계계승효응,득출료경상하유천층니사조제적산사광강성상관특성적결론.근거상하유산사광적상관특성,추도료류속측량공식,병분석료상하유측량간거、수류류속、채양솔대측량결과적영향.탑건료실험계통,재6충불동표정류속하,분석료불동함사량대측량정도적영향.실험결과표명,재0～50 kg/m~3 6충불동함사량정황하,실측류속여표정류속적일치성균교호,단수체재10～50 kg/m~3괄량함사정황하,측량정도교불함사정황유소제고,측량절대오차균소우0.1 m/s,상대오차능공제재8%이내.
Aimming at the technological actuality of surface flow velocity measurement, a novel noncontact photoelectric measuring method for surface flow velocity is proposed. By deducing scattered light intensity formulae, it is concluded that scattered light intensities modulated by both up and down stream shallow sediments have cross-correlated characteristics based on sediment succession effect in shallow water.A formula for flow velocity measurement is derived and the effects of the measuring distance between up and down streams,flow velocity and sampling ratio on the measuring results are analyzed based on the cross-correlated characteristics.Then,an experimental system is set up, and the flow velocities are measured at 6 different flow rates in the cases of 6 sediment concentrations. The experimental results show that the measured flow velocity is coincident very well with the calibration flow velocity under six different sediment concentrations,which proves the feasibility of measurement theory. Experimental results also show that the absolute errors can be controlled to less than 8% and the correlative errors within 8% under the circumstances of suitable sediment in liquid.