That trial found that at length equal to 19.6 cm effective length is the length of a rectangular pipe pipe 100% and the length equal to length of a centimeter 20.17 efficiency of circular pipe.
The experiments showed that at a length of 19.6 cm is the effective length of the pipe, rectangular pipe length 100%. And a length of 20.17 cm is the effective length of the cylinder pipe.
The experiment found that at length 19.6 cm effective length is the length pipe 100% of the square tube and a length 20.17 cm long with the performance of a circular pipe