[題目] 熱力學的問題
[領域] (題目相關領域)
熱力學
[來源] (課本習題、考古題、參考書...)
課本習題
[題目]
Water flows steadily through a feedwater heater, being heated by two sources:
one source adds 1000 kW from a 100 deg-C reservoir and the other source adds
heat from a 200 deg-C reservoir. Water enters with a mass flow rate of 5 kg/s
at 5 MPa, 20 deg-C and leaves at 5 MPa and 180 deg-C. (a) Determine the rate
of entropy generation in the system's universe in kW/K. (b) the exergetic
efficiency in percent. Use the SL model for water.
[瓶頸] (寫寫自己的想法，方便大家為你解答)
想請問一下版上的前輩一題熱力學的習題.
想請問一下.在這種有兩個熱源的情況下.
應該要怎麼處理..?
應該要把它當成兩個不同的 single flow 再做平均嘛 ??
假設沒有輸出功...(題目沒寫就當作他沒有囉..XD)
我有試著直接代入 entropy equation ,可是一直得到負值.
應該是不可能的吧..@@~
感謝回答的前輩..謝謝
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