Instructions:
1. Input gamma (ratio of specific heats),
2. Select input variable and value,
3. Hit Calculate.
Calculations are made for adiabatic flow of a calorifically perfect gas through a constant area duct with no external work. Under such circumstances the flow will move toward the sonic (choked) condition as frictional effects raise the specific entropy. Pipe friction models can be employed to calculate the change in specific entropy and hence the change in Mach number in the pipe. The friction factor f is found independent of the Reynolds number and is assumed to be a function of the relative roughness of the pipe alone and independent of the fluid properties.
This calculator will determine the other Fanno line properties given one of them. If the value of (f Lmax)/D or p0/p0* is specified, you must select from the subsonic or supersonic solution consistent with that value.