Answer:
a) [tex]r_a=37.8m^3/h[/tex]
b)[tex]Q=2.8Kw[/tex]
Explanation:
Temperature of CH_4[tex]t=25C[/tex]
CH_4Flow rate of [tex]r=27m3/h[/tex]
Air Percentage [tex]=140\%=1.4[/tex]
Temperature of air [tex]t_a=127=>400K[/tex]
Temperature at exit[tex]t_e=427C=>700k[/tex]
Generally the equation for Air's flow Rate is mathematically given by
[tex]r_a=air\%*r[/tex]
[tex]r_a=1.4*27[/tex]
[tex]r_a=37.8m^3/h[/tex]
Generally the equation for Ideal Gas is mathematically given by
[tex]PV=mRT[/tex]
[tex]m=\frac{PV}{RT}[/tex]
[tex]m=\frac{1.01*10^5*37.8}{0.287*10^3*400}[/tex]
[tex]m=33.35kg[/tex]
Therefore
The rate of heat transfer from the furnace, in kJ/h is
[tex]Q=mC_p(T_e-T_a)[/tex]
[tex]Q=33.35*1.005*(700-400)[/tex]
[tex]Q=2.8Kw[/tex]