Question

Radiation from a heater is used to heat the still and produce vapor steam as shown here. The heater is maintained at 1000C. The surrounding temperature is 27C. By employing a hypothetical surface for the side surface between Al and A2 to form an enclosure, a radiative circuit can be plotted as shown. Take D= 200mm, D2 = 250mm, H = 100mm.&1 = 0.8. Water latent heat of vaporization is 2.26 x 106J/kg. vapor ED RE J Ra 3 Coaxial Parallel Disks (Figure 13.5) R=r/L, R;=r/L 1+R Rss S=1+ R † Ra Water, 100°c - sunfuce A., & -Heater, senface Az, E. 1000 C Fy=- 15° - 461,13149 E. ta 8.

Please help and solve

Answer 1

+ + Raz J. - J3 + t RIB 90 0,5 to 5530.6 - 1097.535 for Node J. Jy - Ja J₂ J2 Eb2-J2 R23 R2 node J3 J2 J3 Eb3-J3 R23 R3 Ez = 1 ; R2 = 1- Ez 1-1 EzAz E2A2 Replacing Jebe & J3 =Eb3 Ebz-Jg Eng - Ja Eb, - Ja R12 Ra3 Rs 148 900,677 - Ja 12010459.27-J 1097,535-51 248.805 261,578 7.961 738.083 0.13 34 J, Jp = W/m2 Q.6) Vapour production rate, (ºw) qs = Jy - Eba -556.847W R1 7.961 es - & heat eate gained by water 556.847W = in whfg = nw x 2,26x106 t + + + 5530. 6 W Jl kg

mw=2.4639 X 10 -4 kg/s iw = 0.0147 kg min 0.7 If side surfaces are insulated, then, q3=0 رمایا 2 = 9 ER 43-0 JA R13 J3 R12 1 R23 (52 = Ebz {R2=0 Ebz * ag R23 are in series and R13 2.8 - Rnet, 123 Roz3t R13 30,285 + 261,578 291.863 and Rnet, 123 in pordelo pas allel Rez 1 + + Rnet ő RIL Rhet, 123 248,805 291.863 Rnet = 134. 31 Ebi Resulting circuit R1 Rnet 24 J₂ = Ebz

E mw = 4.59 6x 10 = 0,0275 Rg/min production -- 92 - Ebz-Ebi Rnet + R1 146 900.677 - 1097.535 134.31 + 7.961 q 4 = 1038.884 W inw hag 1038.884 = mw x 2.26 X 106 A kg Is vapour mw