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Saladsamurai
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I need some clarification! Thermo Cycle
One kg of Refrigerant 22, initially at p1=.9MPa, u1=232.92 kJ/kG, is contained within a rigid closed tank. The tank is fitted with a paddle wheel that transfers energy to the refrigerant at a constant rate 0.1kW. Heat transfer from the refrigerant to its surroundings occurs at a rate Kt, in kW, where K is a constant, in kW/minute, and t is time in minutes. After 20 minutes of stirring, the refrigerant is at p2=1.2 MPa, u2=276.67 kJ/kG. No overall changes in KE or PE occur. (a) For the refrigerant, determine the Work and Heat transfer, each in kJ. (b) Determine the value of the constant K appearing in the given heat-transfer relation in kW/min.
U2-U1=Q-W
W=int p*dV
I guess what I really need is some clarification on the term "energy transferred in." Is this a rate of WORK?
Homework Statement
One kg of Refrigerant 22, initially at p1=.9MPa, u1=232.92 kJ/kG, is contained within a rigid closed tank. The tank is fitted with a paddle wheel that transfers energy to the refrigerant at a constant rate 0.1kW. Heat transfer from the refrigerant to its surroundings occurs at a rate Kt, in kW, where K is a constant, in kW/minute, and t is time in minutes. After 20 minutes of stirring, the refrigerant is at p2=1.2 MPa, u2=276.67 kJ/kG. No overall changes in KE or PE occur. (a) For the refrigerant, determine the Work and Heat transfer, each in kJ. (b) Determine the value of the constant K appearing in the given heat-transfer relation in kW/min.
Homework Equations
U2-U1=Q-W
W=int p*dV
The Attempt at a Solution
I guess what I really need is some clarification on the term "energy transferred in." Is this a rate of WORK?
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