Natural Convection: Calculate the heat transfer rate (W) of a 4 m high and 10 m wide large vertical plate which is maintained at 65°C and exposed to atmospheric air at 21°C, with the given properties below: k = 0.0275 W/m-K (thermal conductivity) Pr = 0.7 (Prandtl Number) Vair = 17.2x10-6 m²/s (kinematic viscosity) Vertical plate L Round off your answer to three (3) decimal places.

Natural Convection: Calculate the heat transfer rate (W) of a 4 m high and 10 m wide large vertical plate which is maintained at 65°C and exposed to atmospheric air at 21°C, with the given properties below: k = 0.0275 W/m-K (thermal conductivity) Pr = 0.7 (Prandtl Number) Vair = 17.2x10-6 m²/s (kinematic viscosity) Vertical plate L Round off your answer to three (3) decimal places.

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter11: Heat Transfer By Radiation

Section: Chapter Questions

Problem 11.45P

See similar textbooks

Similar questions

The heat transfer coefficient for a gas flowing over a thin float plate 3-m long and 0.3-m wide varies with distance from the leading edge according to hc(x)=10x1/4Wm2K If the plate temperature is 170C and the gas temperature is 30C, calculate (a) the average heat transfer coefficient, (b) the rate of heat transfer between the plate and the gas, and (c) the local heat flux 2 m from the leading edge. Problem 1.18
3.10 A spherical shell satellite (3-m-OD, 1.25-cm-thick stainless steel walls) re-enters the atmosphere from outer space. If its original temperature is 38°C, the effective average temperature of the atmosphere is 1093°C, and the effective heat transfer coefficient is , estimate the temperature of the shell after reentry, assuming the time of reentry is 10 min and the interior of the shell is evacuated.
5.7 The average Reynolds number for air passing in turbulent flow over a 2-m-long, flat plate is . Under these conditions, the average Nusselt number was found to be equal to 4150. Determine the average heat transfer coefficient for an oil having thermal properties similar to those in Appendix 2, Table 18, at at the same Reynolds number and flowing over the same plate.
A spherical communications satellite, 2 m in diameter, is placed in orbit around the earth. The satellite generates 1000 W of internal power from a small nuclear generator. If the surface of the satellite has an emittance of 0.3, and is shaded from solar radiation by the earth, estimate its surface temperature.
An electrical transmission line of 1.2-cm diameter carries a current of 200 amps and has a resistance of 310-4 ohm per meter of length. If the air around this line is at v, determine the surface temperature on a windy day, assuming a wind blows across the line at 33 km/h.
The air-conditioning system in a Chevrolet van for use in desert climates is to be sized. The system is to maintain an interior temperature of 20C when the van travels at 100 km/h through dry air at 30C at night. If the top of the van is idealized as a flat plate 6 m long and 2 m wide and the sides as flat plates 3 m tall and 6 m long, estimate the rate at which heat must be removed from the interior to maintain the specified
Determine the rate of heat transfer per meter length from a 5-cm-OD pipe at 150C placed eccentrically within a larger cylinder of 85 magnesia wool as shown in the sketch. The outside diameter of the larger cylinder is 15 cm and the surface temperature is 50C.
Experiment No. (5) Heat Transfer, Power Input and Surface temperature Questions and Discussions 1. What is the difference between natural and forced convection heat transfer? 2. What sources of error are there in this experiment? 3. Mention the parameters you utilized during the calculation and discuss them briefly. 4. In what functions does Nusselt number in natural convection differ from forced convection, Discuss. 5. Give two examples of natural convection heat transfer. 6. In natural convetion, what makes the hot part of fluid to move?
Answer all questions strictly otherwise dont attempt it. conduction convection experimentIf the material of the fins can be changed to reduce the total thermal resistance, which material is advantageous to use?If you could change the speed or temperature of the air to reduce the total thermal resistance, how would you change it?List all the causes that can cause errors in your conclusions, and consider how changes in those causes affect the results.
In presence of an external flow when will the convective heat transfer be dominated by free convection and not by the forced convection due to the external flow? Gr ≫ Re². Gr ≪ Re. Gr ≫ Re. Gr ≪ Re For ideal gases, the specific heat capacity at constant pressure, thermal conductivity, dynamic viscosity, and Prandtl number are independent of pressure. How will the ratio of thicknesses of velocity boundary layer and thermal boundary layer change if pressure is increased from 1 atm to 5 atm for the flow of an ideal gas over a flat plate? It will decrease by a factor of 5. It will remain the same. It will increase by a factor of 5. We need to know the actual fluid properties to tell.
A thermocouple junction, which may be approximated as a sphere, is to be used for temperature measurement in a gas stream. The convection coefficient between the junction surface and the gas is h=400W/m².K, and the junction thermophysical properties are ĸ= 20W/m.°K, c= 400J/kg.°K and ρ=8500kg/m³. Determine the junction diameter needed for the thermocouple to have a time constant of 1s. If the junction is at 25°C and is placed in a gas stream that is at 200°C, how long will it take for the junction to reach 199°C?
3- You have experienced convection cooling if you have ever extended your handout of the window of a moving vehicle or into a flowing water stream. With the surface of your hand at a temperature of 30 oC, determine the convection heat flux for a) a vehicle speed of 35 km/h in air at -5 oC with convection coefficient of 40 W/m2 .K and b) a velocity of 0.2 m/s in a water stream at 10 oC with convection coefficient of 900 W/m2.K. Which condition would feel colder? Contrast theseresults with a heat loss of approximately 30 W/m2 under normal room conditions.