A constant flow of 0.01 kg/s of compressed air at a pressure of 4 bar is required at the inlet to a process dryer. The designer decides to supply it

through a long thin pipe (8.00mm internal diameter) without any control valves(thus reducing cost). The pipe is supplied from a large reservoir kept at a constant pressure of 7 bar and temperature of 15°C. The pipe friction factor is0.002. Assume isothermal flow. Determine; the pipe inlet velocity and Mach number, [6 the correct pipe length and the exit velocity. The mass flow to the process dryer needs to be increased to 0.02 kg/s whilst maintaining the original pressure and temperature conditions at the inlet to the process dryer. This is to be achieved by adjusting the reservoir pressure and temperature as required. Assume isothermal flow and determine; the reservoir pressure and temperature required to provide the increased mass flow, [5 marks] how much heat transfer would be required to maintain the isothermal flow conditions. [4 marks] Comment briefly on how the results of this analysis might be affected iftrue isothermal flow was not maintained. [4 marks]