收缩断面 meaning in English
necked down section
reduced-section
Examples
- Acent contract section
交界收缩断面 - ( 1 ) it was found from the obtained results that increasing of flux will led to decrease in froude no . of the following water at the shrinking section which will reduce rate of disspated energy , this will make the protection of dam surface more difficult
主要结论如下;随着流量的增加，消力池收缩断面弗劳德数减小，消力池的消能率减小。坝面平均流速增大，坝面的防护难度增加。 - ( 2 ) validate whether the crest elevation can meet the require of energy dissipation and erosion prevention during the beginning period of flood discharge . ( 3 ) calculate the altitude of downriver cofferdam , and make it meet the require of energy dissipation and erosion prevention . ( 4 ) calculate some average velocity of flow through some sections , including contracted section in stilling basins behind upriver cofferdam , if the hydraulic jump happen in lower reaches of the river . the program will calculate the average velocity of flow of contracted section and the length of the apron
主要设计内容包括：计算上游围堰后消力池的尺寸；验证泄洪初期坝面高程是否能够满足消能防冲需要；计算下游围堰堰顶高程，使其满足泄洪期围堰和坝体过流的消能防冲和工程进度的需要；计算部分断面平均流速，包括：上游围堰后消力池中收缩断面的断面平均流速；坝首和坝末的断面平均流速；当下游河道发生水跃时，计算下游河道的收缩断面平均流速及需要铺设护坦的长度。