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Homework Help: Finding the energy dissipated per cycle in a Stirling Engine

  1. Nov 12, 2016 #1
    1.Recently, we performed an experiment to measure the efficiency of the Stirling Engine. The experimental method can be seen in the image provided. We have been asked to calculate the power dissipation PR and the energy dissipation per cycle WR as part of our lab report. The other variables mentioned are R (the resistance), UR (the measured voltage), n (the revolutions per min), T1 and T2, the temperature of two thermocouples connected to the engine.
    At R = 500Ω, the recorded values are: UR = -3.68V, n = 494 cycles min-1, T1 = 150°C and T2 = 63.2°C.

    • PR = V2/R
    • W = P*t (where W is work, P is power and t is time)

    3. I was able to calculate the Power Dissipation using the above equation (PR = 0.027 W) but I'm totally lost on finding WR. I've tried using the above equation and subbing in WR and PR and finding the time it takes for 1 cycle but that gives me a very small number when compared to the value of WpV = -2.4498J. aa7a619d2a246461bba904a65aa83fdf.png
  2. jcsd
  3. Nov 12, 2016 #2

    Simon Bridge

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    If you know the energy dissipated per second, then it is a matter of knowing how many cycles per second and converting.
    If there are a lot of cycles per second, then the resulting energy per cycle will be very small.
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