The internal flow channel structure of the divergent turntable directly affects the jet performance of the nozzle and determines the effect of cleaning the net. Based on the principle of fluid mechanics, a numerical simulation was carried out on the mechanical characteristics of the flow field in the nozzles with right-angle L-shaped and circular-arc L-shaped channels, and the flow velocity, pressure, cavitation and other parameters were analyzed. The results show that: the fluid in the right-angle L-shaped channel is separated and attached to the wall, vortices are formed on both the inner and outer sides; only vortex is formed on the outer side of the circular-arc L-shaped channel; the flow velocity change rate of the circular-arc L-shaped channel is smaller than that of the right-angle L-shaped channel, and the velocity of the nozzle outlet of the circular-arc L-shaped channel is larger; significant cavitation occurred in the nozzles with two both kinds of channel structures. The cavitation area and maximum atmospheric phase volume fraction of the circular-arc L-shaped channel nozzle are larger than those of the right-angle L-shaped channel nozzle. The research results can provide a theoretical reference for the optimal design of the internal flow channel of the divergent turntable of netting cleaning equipment.