Concept explainers
a)
The amount of ice added.
a)
Answer to Problem 208RP
The amount of ice added is
Explanation of Solution
Write the expression for the energy balance equation for closed system.
Here, energy transfer into the control volume is
Write the expression to calculate the initial entropy of the refrigerant.
Here, initial entropy is
Write the expression to calculate the initial enthalpy of the refrigerant.
Here, initial enthalpy is
Write the expression to calculate the initial specific volume of the mixture.
Here, initial specific volume of the mixture is
Write the expression to calculate the mass of the stream
Here, the initial volume of a container is
Conclusion:
Substitute
Here, change in enthalpy in ice is
From the Table A-4, “Saturated water-Temperature table” the obtain the following properties at temperature of is
From the Table A-4, “Saturated water-Temperature table” the obtain the following properties at temperature of is
Here, the final entropy is
Substitute
Substitute
Substitute
Substitute
From the Table A-3, “Properties of common liquids, solids, and foods”, select the specific heat at constant pressure at room temperature for liquid and ice as
The melting temperature and the heat of fusion of ice at
Substitute
Thus, the amount of ice added is
b)
The entropy generation during the process.
b)
Answer to Problem 208RP
The generation during the process is
Explanation of Solution
Write the expression for the entropy balance equation of the system.
Here, rate of net entropy in is
Conclusion:
Substitute 0 for
Substitute
Thus, the generation during the process is
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Thermodynamics - Connect Access
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