| 摘要 |
PURPOSE:To decelerate a high-speed flow of steam and reduce a pressure loss during a normal operation by a method wherein there are arranged a decelerator device composed of a row of columns having a limited ratio between a pitch and a diameter and rods with stream line shape or tear drop section. CONSTITUTION:Since a number of stages of decelartor devices 30 oppositely arranged against a steam inlet port 17 and with a ratio between pitch and a diameter being 2-10 are installed toward a flow direction with a space more than five times of a diameter of the column, the flow of steam is abutted against the column 31, decelerated, abutted against the side wall 16b, deflected thereby and then guided toward the group of cooling pipes 14. The rods 33 of stream- line shape or tear drop section of the deceleration promoting device 34 are arranged such that their large diameter parts are placed in a vertical upward direction and a ratio between a pitch P and the maximum thickness L of the rod 33 is 2-5, so that an effective forward shock wave and slant shock wave are produced, a loss of steam flow is generated to make a sufficient effect of deceleration. During a normal operation, the rods 33 of the decelerator device 34 have a viscosity resistance of less than 1/10 compared to the columns, so that a pressure loss is scarecely applied to the discharging flow of turbine. |
