The pressure distribution and flow resistance characteristic in cavity of turbine casing was summarized by experiment of measuring the pressure distribution of whole cavity of turbine casing with different Reynolds numbers (80000 to 260000). The experiment results show that: (1) the pressure drop is obvious

and there is a large pressure loss in the transition zone between the second and third tanks; (2) the static pressure coefficient increases with the increasing Reynolds number

and the maximum increament is about 19%; (3) the total pressure loss coefficient varies stably with the Reynolds number increasing

and the difference is below 10%.