Abstract: Energy recovery devices is a core component of reverse osmosis desalination systems, which significantly reduce water production energy and costs. The output flow quality of the device greatly affects reverse osmosis membrane performance, lifespan, and system stability. A lumped parameter model is presented for axial piston booster pump（APBP） in integrated energy recovery-pressure boosting device（IERPBD）, incorporating cavitation effects. Following ISO 10767-1-2015, a flow ripple test bench is constructed, and tests are conducted at the outlet of IERPBD. The source flow ripple and source impedance of APBP are derived based on theoretical methods, and the actual flow ripple and pressure ripple at the outlet of the device under different operating conditions are calculated. The variation patterns of flow ripple and pressure ripple under different working conditions have been identified:the average flow and average pressure rise as the rotation speed escalates; and it has been observed that flow ripple and pressure ripple also tend to escalate with the increase in rotation speed, but a reduction is noted at 1 700 r/min. The experimental results show that the maximum RMSE for the pressure characteristic curve does not exceed 0.121, and for the flow characteristic curve it remains below 0.538. The close agreement between the measured and simulated data provides a theoretical basis for optimizing the design of IERPBD to improve flow quality, and offers practical guidance for the application of energy recovery devices in seawater desalination.

Key words: seawater reverse osmosis desalination, energy recovery, lumped parameter method, flow ripple, 2P2S test method