Modify Prob. P6.124 as follows: Let all data be the same except that pipe 1 is fi tted
Chapter 6, Problem p6.126(choose chapter or problem)
Modify Prob. P6.124 as follows: Let all data be the same except that pipe 1 is fi tted with a butterfl y valve (Fig. 6.19b). Estimate the proper valve opening angle (in degrees) for the fl ow rate through pipe 1 to be reduced to 1.5 ft3 /s toward reservoir 1. (This problem requires iteration and is best suited to a computer.)
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