Gases isothermal efficiency, pumping

The turboexpander in combination with a compressor and a heat exchanger functions as a heat pump and is analyzed as follows In Fig. 29-44 consider the compressor and aftercooler as an isothermal compressor operating at To with an efficiency and assume the working fluid to be a perfect gas. Further, consider the removal of a quantity of heat by the tumoexpander at an average low temperature Ti-This requires that it dehver shaft work equal to Q. Now, make the reasonable assumption that one-tenth of the temperature drop in the expander is used for the temperature difference in the heat exchanger. If the expander efficiency is and this efficiency is mul-... 

Hydrogen is pumped from a reservoir at 2 MN/m through a clean horizontal mild steel pipe 50 mm in diaraeter and 5tX) m long. The downstream pressure is also 2 MN/m and the pressure of the gas is raised to 2.5 MN/m" by a pump at the upstream end of the pipe. The conditions of flow are isothermal and the temperature of the gas is 295 K. What is the flowrate and what is the eflective rate of working of the pump if it operates with an efficiency of 60 per cent ... 

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