In: Mechanical Engineering
List the conditions to be met for a thermodynamic process to be accurately described as a steady state, steady flow process. Write down a mathematical expression for the First Law of Thermodynamics as applied to such a process, explaining clearly the notation and sign conventions used. A pumped domestic shower unit incorporates an electrical resistance heater to increase the temperature of liquid water before it is directed towards the shower head. The heater in a specific model draws 7.2 kW of electric power and operates in a steady state with an inlet water supply temperature of 5degrees celcius during cold weather. (A) What inlet water flow rate (in litres per minute) can be sustained if the outlet water temperature is to be 50degrees celcius at the exit from the heater? (B) What exit temperature (oC) would be achieved if this water flow rate were increased by 60%?