A) Determine the convection heat transfer coefficient for the flow of air. [W/m2·°C]
B) Determine the convection heat transfer coefficient for water. [W/m2·°C]
A) Determine the convection heat transfer coefficient for the flow of air. [W/m2·°C] B) Determine the...
A counter-flow heat exchanger is stated to have an overall heat transfer coefficient of 284 W/m2.K when operating at design and clean conditions. Hot fluid enters the tube side at 101°C and exits at 71°C, while cold fluid enters the shell side at 27°C and exits at 42°C. After a period of use, built-up scale in the heat exchanger gives a fouling factor of 0.0004 m2 K/W. The surface area is 93 m². Assume both hot and cold fluids have...
(a) (iWhen is heat transfer through a fluid by conduction or by convection? For what case is the rate of heat transfer higher? How does the convection heat transfer coefficient differ from the thermal conductivity of a fluid? (ii) Explain the physical significance of Nusselt number (ii) By definition, discuss hydraulic diameter. Obtain an expression for hydraulic diameter of a circular tube of diameter, D (b) The local atmospheric pressure in Gboko, Benue State Nigeria (elevation 1610 m), is 834...
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...
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...
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 kairRe13/D, 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...
Waste heat of exhaust hot air from a manufacturing process may be recovered by passing water through a thin-walled tube of 1.00 cm diameter as shown. Assume the temperature of the hot air is 177℃ in cross flow with a velocity of 20 m/s over the tube. The inlet and outlet temperature of water are 20C and 60 C, rospectively, and the ilow rate is 0.2 k/s. Deiemine (a) the total heat transfer rate from air to water, (b) The...
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 kairRe13/D, 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...
The equation for the local heat transfer coefficient h, for a fluid flow of velocity Vin the x direction over a specific constant temperature surface is Nuz = CRe: Prn where C and n are constants. Assume the fluid properties k, p, Pr, V, and Cp are constant and known. The heat transfer coefficient over the entire surface is governed by this equation. At a position x1 = 20 cm from the leading edge of the plate, the local heat...
I need Q5 Heat transfer Problem(.) In an experiment, it is found that the local convection coefficient on a flat plate of length L is given by: (10 marks) h,-o923 (k/x){(V. ?.?)/p)as, where k, V, p, and ? are constants. Determine the average convection coefficient over the plate h Problem (5) (10 marks) Milk is flowing with a mass flow rate m 0.6 kg/s, in a pipe with internal diameter - 3 cm. Its initial temperature is 50 °C and...
Problem 2: Heat exchanger (25 points) Cold water (op 4179 J/kg K) enters the tubes of a heat exchanger at 20 °C at a rate of 3 kgs. while hot oil (cp 2200 J/kg.K) enters the shell at 130 C at the same mass flow rate and leaves at 60°C The heat exchanger consistsoftwo shells and 20 tubes, each executing four passes (two passes per shell). If the W/m2-K, assume the tube wall is very thin with convective heat transfer...