Engineering, 19.03.2020 00:04 crickel40pa8sxe
Electric heater wires are installed in a solid wall having a thickness of 8 cm and k=2.5 W/m.°C. The right face is exposed to an environment with h=50 W/m2°C and k'=30°C, while the left face is exposed to h=75 W/m2°C and T[infinity]=50°C. What is the maximum allowable heat generation rate such that the maximum temperature in the solid does not exceed 300°C.
Answers: 1
![300=-\frac{q^.}{2k} [c_{1} \frac{k}{q} ]^2+c_{1} [c_{1} \frac{k}{q} ]+c_{2} (1)](/tpl/images/0552/9289/e7117.png)
![75[50+\frac{q^2}{2k} (0.04)^2+c_{1} (0.04)-c_{2} ]=-k[\frac{+q^2(0.04)}{2k} ](2)](/tpl/images/0552/9289/ef1e8.png)
![-k[\frac{-q^.(0.04)}{2k} ]=50[\frac{-q^.(0.04)}{2k} +c_{1} (0.04)+c_{2} -30](3)](/tpl/images/0552/9289/38a2d.png)
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Electric heater wires are installed in a solid wall having a thickness of 8 cm and k=2.5 W/m.°C. The...
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