adiabatic vs isothermal

For the same pipe size, when flow is adiabatic(eg. insulated steam line) the flow obtainable is more compared to isothermal flow.Why is it so.Someone could help me out.

Gratitudes in advance.

 

[TD2K]

I'm not sure what you are asking by 'is more compared to isothermal'.

An insulated steam line is pretty much adiabatic and it's also isothermal. Can you rephrase your question?

 

[poetix99]

I wonder if you are referring to "flows in long ducts" - a topic of any compressible flow text (e.g. "The Dynamics and Thermodynamics of Compressible Fluid Flow" - Ascher M. Shapiro)

Steam typical of many industrial applications is not superheated enough to be very close to a perfect gas. Any perfect gas analysis, such as in the text referenced above, will be in error, especially if the steam is a saturated mixture.

As TD2K has suggested, you should rephrase your question.