Helium is to be compressed from 105 kPa and 295 K to 700 kPa and 460K....

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Helium is to be compressed from 105 kPa and 295 K to 700 kPa and 460K. A heat loss of 15 kJ/kg occurs during the compression process. Neglecting kinetic energy changes, determine the power input (kW) required for a mass flow rate of 60 kg/min. Assume the specific heats of helium to be constant and given by their values at 300K. Solution for this problem: Assuming Melium as ideal gas Cp of helium-5-1926 kJ/kg k AKE-0,APE-0 m = 60kg/min = 1 kg/sec == -15 kJ/kg m Using Steady state flow process from First law of thermodynamics - W = m (h-h) W = &- m (h-h) = -m cp (T2-T) =-15xm-m (T2-T) = 5-1926 (460-295) m-15-51 1x-15-856-779] -871-779 kW Based on this Problem: It turns out that the conditions specified in this problem were not realistic at all. For the process to be at least possible, how cold must the ambient temperature be? Helium is to be compressed from 105 kPa and 295 K to 700 kPa and 460K. A heat loss of 15 kJ/kg occurs during the compression process. Neglecting kinetic energy changes, determine the power input (kW) required for a mass flow rate of 60 kg/min. Assume the specific heats of helium to be constant and given by their values at 300K. Solution for this problem: Assuming Melium as ideal gas Cp of helium-5-1926 kJ/kg k AKE-0,APE-0 m = 60kg/min = 1 kg/sec == -15 kJ/kg m Using Steady state flow process from First law of thermodynamics - W = m (h-h) W = &- m (h-h) = -m cp (T2-T) =-15xm-m (T2-T) = 5-1926 (460-295) m-15-51 1x-15-856-779] -871-779 kW Based on this Problem: It turns out that the conditions specified in this problem were not realistic at all. For the process to be at least possible, how cold must the ambient temperature be?