Concept explainers
(a)
The rate of water must supplied to maintain steady operation.
(a)
Answer to Problem 156RP
The rate of water must supplied to maintain steady operation is
Explanation of Solution
The rate of water must be supplied to maintain the steady state operation is equal to the rate of water removed by the bottles.
The rater water removed by the bottles is expressed as follows.
Conclusion:
Substitute
Thus, The rate of water must supplied to maintain steady operation is
(b)
The rate of heat must supplied to maintain steady operation.
(b)
Answer to Problem 156RP
The rate of heat must supplied to maintain steady operation is
Explanation of Solution
Consider bottles flow alone and the system is in steady state. Hence, the inlet and exit mass flow rates are equal.
The mass flow rate of bottles are as follows.
Write the energy rate balance equation for one inlet and one outlet system.
Here, the rate of heat transfer is
Consider the system is at steady state. Hence, the rate of change in net energy of the system becomes zero.
Neglect the work transfer, kinetic, and potential energy changes. The heat transfer occurs water bath to bottles. The bottles heated by the hot water bath i.e. the heat gained by the bottles.
The Equations (II) reduced as follows for bottles.
Write the formula for change in enthalpy
Here, the specific heat of chicken at constant pressure is
Substitute
Here,
Write the formula for heat removed by the water that is carried by the bottle.
Here, the specific heat of water is
The rate of heat must supplied to maintain steady operation is equal to the total heat removed by the glass bottles and water carried by the bottles.
The total heat removed from the hot water bath is expressed as follows.
Refer Table A-3(a), “Properties of common liquids, solids, and foods”.
The specific heat of water
Refer Table A-3(b), “Properties of common liquids, solids, and foods”.
The specific heat corresponding to glass, window (glass bottles)
Conclusion:
Here, the bottles enters the hot water bath at the rate of 450 bottle per minute and each bottle weighs
Thus, the mass flow rate of bottles
Substitute
The heat removed by the bottles is,
Substitute
Substitute
Thus, the rate of heat must supplied to maintain steady operation is
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Chapter 5 Solutions
Thermodynamics: An Engineering Approach
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