Abstract: The polysilicon reduction furnace serves as the core reactor for polysilicon production.To optimize the output and reduce the energy consumption, this study investigates the effects of inlet gas velocity and inlet/outlet area ratio on silicon deposition rate and energy consumption in a 72-pair rod polysilicon reduction furnace through numerical simulations, based on the gas-phase and surface reaction mechanisms of chemical vapor deposition（CVD） in the TCS-H₂ system.Results indicate that the silicon deposition rate increases with higher inlet gas velocity, which also improves deposition uniformity, with the average deposition rate remaining within 0.001 4～0.001 5 kg/（m²·s）.The inlet/outlet area ratio has a minor influence on the deposition rate, with the average rate peaking at 0.001 495 kg/（m²·s） when the ratio is 0.6.When the wall emissivity（ε） of the furnace is 0.55,at lower inlet gas velocities, radiative heat transfer between the outer rods and the furnace wall dominates, leading to higher energy consumption for the outer rods.When the intake gas velocity is relatively high, the heat exchange between the silicon rods and the gas flow in the furnace intensifies, resulting in higher energy consumption for the silicon rods with high turbulence.When ε=0.25,the total energy consumption slightly decreases as the inlet/outlet area ratio increases, reaching its minimum at a ratio of 1.4.