Abstract: Pressure-compensating(PC)emitters are complicated structurally and the working mechanism is not clear to us, which causes big difficulty in their research and development. Simulation and visualization experiment for the PC chamber is important to reveal PC emitters’ working mechanism. So fluid-structure interaction(FSI) analysis on the hydraulic performance of PC emitters with ADINA software is studied. Transparent organic-glass test model with the same size as the real product is manufactured, and visualization experiments are carried out through a measuring system and a digital particle image velocimetry (DPIV) system. Deformations of the diaphragm are acquired under different pressures. It shows that the increase of the diaphragms deformation slows down with pressure. In the experiment, it is found that the diaphragm vibrates from inlet pressure of 75 kPa to 195 kPa. After that, the diaphragm fits closely to the PC chamber top, leaving only the little groove as the main flow channel. This means the discharge is adjusted through the diaphragms tiny deformation during the constant-discharge stage. Combining with pressure distribution obtained from FSI analysis, the conclusion that the small flow section formed by the diaphragm and the inside wall is quite important to the hydraulic performance of the emitter is got. From DPIV experiments, velocity distributions of different sections are obtained. The experimental values agree well with the simulation results. In conclusion, FSI analysis together with visualization experiment is an efficient way to study PC emitters working mechanism and guide their design.

Key words: diaphragm deformation, fluid-structure interaction, pressure-compensating emitter, velocity distribution, visualization experiments