Answer:
22.474 KW
Explanation:
We have given casting surface [tex]a=6.5m^2[/tex]
Surface temperature [tex]T_1=400^{\circ}C=400+237=673K[/tex]
Foundry temperature [tex]T_2=30^{\circ}C=273+30=303K[/tex]
Emissivity of grey = 0.31 given
Now the rate heat of heat radiated from the casting is
[tex]Q_{radiated}=\epsilon A\sigma \left ( T_1^4-T_2^4 \right )[/tex]
Here [tex]\sigma =5.67\times 10^{-8}[/tex]
So [tex]Q_{radiated}=0.31\times 6.5\times 5.67\times 10^{-8}\left ( 673^4 \right-303^4 )=22474.846\ W=22.474KW[/tex]
