Question

1 During air cooling of oranges, grapefruit, and tangelos, the heat transfer coefficient for combined convection, radiation, and evaporation for air velocities of 0.11 < V< 0.33 m/s is determined experimentally and is expressed as h=5.05 kairRe131D, where the diameter Dis 0.1 m. Oranges are cooled by refrigerated air at 5°C and 1 atm at a velocity of 0.3 m/s. Given: The thermal conductivity of the orange is given to be k = 0.50 W/m-°C. The thermal conductivity and the kinematic viscosity of air at the film temperature of (T, + T.)/2) = (15+5)/2 = 10°C are k = 0.02439 W/m.°C, v =1.426 x 10-5 m2/s. 3. value 3.00 points Required information Determine the initial rate of heat transfer from the orange that is initially at 15°C with a thermal conductivity of 0.50 W/m.K. (Round the final answer to two decimal places.) The initial rate of heat transfer from the orange is W. Check my work

Answer 1

air. assume Spherical shape D=0.2 m isc Orange sc Vair 0.3m/ Re = DVD VD 0.3x 0.1 1.426x10 2103.78 M ain Y₃ h = 5.05 kair Re =5605 x 0.02439 (2103.78393 0.1 = 15.7822 W/m2k. Inital Rate of heat transfer from the orange Thx A surface & (Ti-To) Area Asurface 4 kr no2 Arca EX612 - 15:78 22 * * x13*8(15-5) 40958 walt