Wave-rotor-based gas pressure dividing (GPD) is a potential technology that can synchronously conduct gas compression and expansion. This study, proposes a novel curving flow channel of wave rotor (C-FCWR) for the three-port GPD device, aiming to settle the technical problem of traditional width-constant straight flow channels (WS-FCWR). A series of comparative hydrodynamics and thermodynamic analyses are conducted. For the optimized C-FCWR with a forward-curving angle of +10°, the flow vortex generation in the medium-pressure (MP) and low-pressure (LP) ports is rather limited, the shaft power is as low as -0.45 kW, the shock wave efficiency is beyond 99.8 %, and the expansion depth remains above 26.4 K, proving a great technical advantage. For the application feasibility of the optimized C-FCWR to working conditions, a compression ratio below 1.2 and an expansion ratio of 1.8 are conducive to the overall performance of the GPD device.