提出电阻法测量自来水管漏水点实验方案,其原理为:沿水管铺设两根相互平行、与管道同长的相同电阻丝,电阻丝与水管间放置浸泡过NaCl饱和溶液后晾干的纱布.电阻丝两端都设置电压一定的电源,某点水管泄漏,漏水点处纱布中的NaCl晶体溶解,在平行电阻丝间形成导电盐桥,同时测量电阻丝两端电压及电流,可消除漏水处盐桥电阻对于测量结果影响,计算漏水点到电阻丝端点阻值,并进一步根据电阻定律计算漏水点到电阻丝一端距离.利用上述实验方案,对长度为2 m的水管不同漏水点位置进行了实验测量.结果显示,漏水点定位最大误差小于8 cm,测量结果较为准确,从而证明上述测量法测量结果准确,测量原理及方案可行.
Based on the resistance law, a method of measuring the leak point of the water pipe is presented. The principle is given below. Two same thin resistance wires are parallel layed along with the water pipe, a piece of drying gauze, which has been immerged in the saturation NaCl solution is put between the resistance line and water wire, two electrical sources with certain vohage is set at the two ends of the resistance wires. When the water leaks from the pipe at one point, the NACL in the gauze dissolves, such that two parallel resistance wires eondueling at the water leak point. Along the two parallel wires, two closed circuits can be available. Measuring the voltages and currents from two ends of the parallel resistance wires at the same time, the resistance value from the water leak point tu the end of one resistance wire can he eah'ulaled based on the Kerchiefs w)hage law. According to the resistance law, the length from the water leak point to one end of the resistance wire can be ohtained. By use of the ahove method, the leak points of a lwo meters water pipe are measured. The measuring result shows that the maximum measuring error is less than 8 centimeters, henee the measuring resnhs of this method is accurate, and the measuring method is viable.