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2. A natural gas is flowing through a 1m diameter and 6.5km long pipeline (friction factor =0.0024 ) at a constant temperature of 15C. The pressure at the inlet of the pipe is 5.7MPa. What is the maximum mass flow rate of the gas that can be achieved and the corresponding downstream pressure? [Ans. Gmax=1012.3kgs1,Pw=498.6kPa ] Use the following data for solving problems: Viscosity of methane ()=0.011103kgm1s1 Molecular weight (M)=16.0kgkmol1 Universal gas constant (R)=8314Jkmol1K1