Self-recording different sand content water flow rate measuring device and measuring method

The invention discloses a self-recording different sand content water flow rate measuring device and measuring method. The device comprises a floating ball, an inelastic connecting rope, a slip ring, an elastic upright post, a stress sensor and a data acquisition recorder. The method comprises: (1) preparing a muddy water sample with different sand content S, measuring the content D of each diameter of sand grains in the muddy water sample, pouring the muddy water into a simulated channel at different flow rate to obtain water flow with different flow rate, acquiring the actual flow rate U of the water flow by using a noncontact electronic current meter, meanwhile, obtaining the bending stress F of the elastic upright post via the stress sensor, and establishing a corresponding relation among U, F, S and D according to the series of experimental data to obtain U=(F, S, D, F*S, F*D, S*D); and (2) substituting the content D of each diameter of sand grains of the water flow, the sand content and the bending stre