﻿ Calculation of Peak efficiency flow of Francis turbines by RETSCREEN® ENGINEERING & CASES TEXTBOOK

# Calculation of Peak efficiency flow of Francis turbines by RETSCREEN® ENGINEERING & CASES TEXTBOOK

 1 Specific speed based on flow：nq - 2 Design flow：Qd m^3/s - 3 Graph x-axis:nq,y-axis：Qp x-axis:Qd,y-axis：Qp x-axis:nq,y-axis：0.65*nq^0.05 Plot Input Data： YesNo 4 Number of gridlines of Graph x-axis, y-axis -
:Export Graph Image.

## Keyword

Peak efficiency flow,Turbine peak efficiency,Runner size adjustment to peak efficiency,francis turbines,specific speed based on flow, Runner throat diameter,turbine manufacture/design coefficient

## Reference

[1]：RETScreen® International『CLEAN ENERGY PROJECT ANALYSIS：RETSCREEN® ENGINEERING & CASES TEXTBOOK SMALL HYDRO PROJECT ANALYSIS CHAPTER』.pp.37-51.

## Remarks

・Qp：『Peak efficiency flow』(Reference[1])
・Qd：『design flow(flow at rated head and full gate opening in m^3/s)』(Reference[1])
・ep：『Turbine peak efficiency』(Reference[1])
・Rm：『turbine manufacture/design coeffi cient(2.8 to 6.1; default = 4.5).』(Reference[1])
・^ed：『Runner size adjustment to peak efficiency』(Reference[1])
・^enq：『Specific speed adjustment to peak efficiency』(Reference[1])
・nq：『specific speed based on flow』(Reference[1])
・d：『runner throat diameter』(Reference[1])