A shear-force measurement method based on fiber Bragg grating (FBG) sensing technology is proposed to exert the real-time measurement of shear-force distribution on the membrane in forward osmosis (FO) process. The effects of different inlet flow rates on shear-force distribution

water flux and reverse salt flux (RSF) were investigated

and the hydraulic properties of membrane interface behavior were analyzed. The FBG results show that the FBG technique can better give the membrane shear-force shift in the FO module. The shear-force variation presented identical periodicity

and a non-uniform spatial variation of the shear-force distribution exists along the FO membrane surface

which directly leads to the change of water flux. Besides

the shear could be effectively improved at all locations on the membrane by increasing the inlet flow rate

but the larger flow should be applied to significantly improve the shear force farther from the inlet. The simultaneous increase of the shear force on both sides of the membrane module is beneficial to improve water flux

but simply increasing the shear force couldn't better reduce the concentration polarization (CP) and get higher flux.