【摘要】 本文运用Ｇａｒｄｅｌ的Ｔ型分岔管水头关系式，分析了连接管处速度头和动量交换项对下游调压室稳定断面积的影响．在托马假定的前提下，导出了相应的计算公式．从而在理论上证明了连接管处速度头对下调稳定不利，而动量交换项则是有利的，两者作用可大致抵消，结果接近简单式调压室的托马断面．若合理选取连接管的尺寸和型式，可进一步减小下调水位波动稳定所需的断面积．更多还原

【Abstract】 The velocity head and momentum distribution in the T-section of adownstream surge tank affecting the critical stable sectional area of the tank havebeen analyzed in this paper by using Gardel’s head loss expression and a new formula of the critical stable sectional area has been derived by the authors. The investigations show that the velocity head has a negative effect on the stability ofdownstream surge tank, while the effect of the momentum distributinn ispositive. Two effects can be counterated. If the size and shape of riser areoptimized, the sectional area of the surge tank can be further reduced.更多还原