surface temperature of a 12 m long and a 6-cm-diameter horizontal hot water pipe is 73 ℃. Assume the air temperature to be 27 ℃. Determine the rate of heat loss from the pipe by free convection. Properties of Air are: k = 0.02735 W/m.℃, ν = 1.798*10^-5 m2/s, Pr = 0.7228, β= 1/Tf = 0.003096 K^-1. Select one:

Required information Air flows in a pipe under fully developed conditions with an average velocity of 1.25 m/s and a temperature of 24°C. The pipe's inner diameter is 4 cm, and its length is 4 m. The first half of the pipe is kept at a constant wall temperature of 100°C. The second half of the pipe is subjected to a constant heat flux of 200 W. The properties of air at 80°C are p = 0.9994 kg/m³, k = 0.02953 W/m-K, v= 2.097 x 10-5 m²/s, cp=1008 J/kg-K, and Pr = 0.7154. NOTE: This is a multi-part question. Once an answer is submitted, you will be unable to return to this part. Air 1.25 m/s 2m T, = 100°C D = 4 cm 2 m g, = 200 W Determine the wall temperature at the exit of the tube. The wall temperature at the exit of the tube is 282 * °C.

Thermodynamics problem. A membrane type electrical heater of 20,000 w/m? capacity is sandwiched between an Insulation of 25 mm thickness with thermal conductivity of 0.029 W/m-K and a metal plate with k = 12.6 W/m-K of thickness 15 mm. The convection coefficient is 150 W/m2-K. The surroundings are at 5°C. Determine the surface temperature of the heater and the flow on either side.

Water flows over a heated plate as shown below. The plate length is 0.17 m and its boundary condition is set as constant heat flux. Water flow velocity is 2 m/s and uniformly distributed heat flux is 75000 W/m2. Thermophysical properties of water may be approximated as: k = 0.620 W/mK, Pr = 5.2, ν = 0.96x10-6 m2/s