1 Answer

HI  IT IS IMPOSSIBLE TO CALCULATE AN ACCURATE MPH WITH OUT FRICTION COEFICIANTS ETC  BUT AN APPROX FIGURE CAN BE CALCULATED AS FOLLOWS

WORK OUT THE VOLUME PER MIN IN YOUR PIPE MULTIPLY BY 60 TO MAKE IT PER HR THEN DIVIDE BY 5280 TO MAKE IT MPH

IE:     1.25 X Pi   =    1.25 X 3.14159 =3.9269 sq in  =   0.32724 sq ft

DIVIDE THIS INTO       125/0.32724 = 381.98 FT PER MIN X 60  =22918.958 FR PER HR

DIVIDE BY 5280 WHICH IS FT IN MILE      22918.958/ 5290  = 4.3407 mile per hr

ASSUME YOUR SMALL NOZZLE IS    1/4inch dia

1/4 X 3.14159 = 0.786 sq in  =   0.0655 sq ft      125/.0655 =  1908 ft per min x 60 =114480ft per hr    divide by  5280         114480/5280 =   21  mile per hr   approx

AS I HAVE ALREADY STATED THIS IS A VERY CRUDE APPROXIMATION AS THERE ARE A LOT OF VARIABLES WHICH HAVE TO BE TAKEN INTO ACCOUNT

HOPE THIS HELPS

MONDEOMAN