对于闸后为无压明流的平板工作闸门门槽，其水力特性与处在压力段内的事故闸门门槽相差较大。借助于数值计算的帮助，通过对积石峡水电站中孔泄洪洞工作闸门门槽体形试验研究，包括对原设计方案在内的6个方案的水力特性的比较，最后确定第三组修改方案，即加大门槽错距，扩大其下游棱角的弧半径及平缓后接坡度的优化方案，效果是比较好的。

The design technology of plane emergency gate slot form under pressure flow condition is good, but the hydraulic characteristics of plane emergency gate region are different from the plane working gate region under without pressure flow behind the gate. Based on six test results on hydraulic characteristics of plane working gate region of middle outlet at Jishixia hydraulic Power Station with the help of numerical solutions, the appropriate plane working gate slot form,i.e. an optimum scheme including expanding the offset of the slot, enlarging the radius of its downstream angularity and lowering the gradient behind the angularity, is recommended.