Mixed flow pump without seal guide vane design gap

The leakage capacity of the mixed flow guide vane has a great influence on the safety and economic operation of the power station, and the size of the leakage of the mixed flow guide vane has a direct relationship with the design gap of the guide vane, especially for the mixed flow pump. Mixed flow pump without sealing guide vane when the calculation of the amount of water leakage is not set when the sealing of the new guide leaves when the water leakage, according to the principle of thin-walled free jet, according to the following formula. (1) where q-mixed flow pump guide vane leakage, m ya sk- consider the water after the roof, mixed flow pump guide vane deformation of the area of ​​safety factor, according to the actual The total area of ​​the upper and lower end face leakage, m2 A: - the total area of ​​the vertical leakage of the guide vane of the mixed flow pump, the mZ-1 free jet coefficient, the Shanghai-0.97 G-gravity acceleration, g a 9. 81m / s2 H-mixed flow pump guide vane before the average head, usually available power station weighted average head or rated head to calculate, m leakage area calculated by the design gap, according to the relevant standards, When the clearance is fully closed, the elevation of the facade is generally less than 0.08 to 0.15 mm in the range of 1/4 guide vane, and the remaining area is less than 0.05mm in the range of 3/4 guide vane, (MZ) where the number of Z.-guide vanes B.- guide vane height, m ​​this part of the area is generally only a small part of the total leakage area, and the domestic generally according to this Standard design.