- #1

dRic2

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- Homework Statement
- see picture below

- Relevant Equations
- heat transfer equation

To write the equation I took as the control volume the following block:

and the equation I wrote are:

$$ 6m_{f} c_{p_{f}} \frac {dT_{f}}{dt} = 6P - \frac 1 {R_1} (T_f - T_g) \text{ for the fuel}$$

$$ m_{g} c_{p_g} \frac {dT_{g}}{dt} = \frac 1 {R_1} (T_f - T_g) - \frac 1 {R_2} (T_g - T_c) \text{ for the graphite}$$

$$ 3m_{c} c_{p_c} \frac {dT_{c}}{dt} = \frac 1 {R_1} (T_g - T_c) - 3G c_{p_{c}} (T_{out} - T_{in}) \text{ for the coolant}$$

##P## is the power produced by each fuel element. In stationary condition just drop the time derivative. I'm not totally sure about the last one though...

I have no clue on point b). Can someone give me a hint ?

Thanks Ric

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