一道关于水泵效率的物理题目

题目

一道关于水泵效率的物理题目
一个水力发电站和湖面以及下游的溪水相差了Δz = 100m .溪水进入到涡轮机的速率是V=6,000 dm^3/s.这个涡轮机和一个发电机相互连接提供了4.5MW的功率,效率为95%.
计算涡轮机（水泵）自身的效率,以及整个系统的效率和涡轮机自身的功率.水的密度为1kg/dm^3.
A hydropower station has Δz = 100 m level difference between the lake’s surface and downstream water.The water stream to the turbine has a volume rate of = 6,000 dm3/s.A turbine is coupled to an electric generator that produces = 4.5 MW power,and has = 95 % efficiency.
Calculate the efficiency of the water turbine itself in %,the overall efficiency in % and the power generated by the turbine in MW.The density of water is 1 kg/dm3.Give answers to the nearest integer.
如果翻译的不准请参照英文版,

答案

已知每秒进入涡流机的水为6000升.则可知水的重力势能做功为mgh=6000×10×100=6×10^6 J【焦耳】因为是单位时间,即功率为6MW,4.5/6=3/4则显而易见,系统的效率为75%,4.5/0.95=180/1919×6/180=0.6333333即涡轮机的效...