初探挑流冲深的模糊估算

Initial Fuzzy Estimation of Free Jet Scour

鼻坎下游的挑流冲刷受众多因索影响,由于现象复杂和不确定性,冲刷具有某种模糊性,可用模糊集理论估算冲深.单宽流量、水头落差和岩床特性为最重要的因素,由154组原型数据和270组常用公式"咨询数据"形成了挑流冲深数据库.对一定的水力条件和岩床特性可用模糊模型估算挑流冲深.对几个原型的估算值与实测值所进行的比较表明,该模糊模型的估算是合理的.

Free jet scour below flip buckets is affected by several factors. Owing to its complexity and uncertainty, the scour phenomenon has some fuzzy properties, the scour depth could be estimated by using fuzzy sets theory. Unit flow discharge, water head drop and the rockbed feature axe the most important factors. The databank of the free jet scour depth includes 154 sets of 'original' data measured in prototypes and 270 sets of 'consulted' data calculated by 8 authoritative formulas. Under certain hydraulic conditions and some rockbed featrurs the maximum scour depth downstream of flip buckets could be estimated by the fuzzy model presented in this paper. The comparisons between the values measured in several prototypes and the estimated values for them show that the scour depth estimated by the fuzzy model is quite reasonable.