5. A 500 m dark-colored swimming pool is located in a well-sheltered site where the measured wind speed at 10m height is 3 m/s. The water temperature is 25 °C, the ambient air temperature is 17 °C, and relative humidity is 60%. There are no swimmers in the pool, the temperature of the make-up water is 22 °C, and the solar irradiation on a horizontal surface for the day is 20.2 MJ/m² day The amount of energy must the solar system

5. A 500 m dark-colored swimming pool is located in a well-sheltered site where the measured wind speed at 10m height is 3 m/s. The water temperature is 25 °C, the ambient air temperature is 17 °C, and relative humidity is 60%. There are no swimmers in the pool, the temperature of the make-up water is 22 °C, and the solar irradiation on a horizontal surface for the day is 20.2 MJ/m² day The amount of energy must the solar system

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.

Chapter5: Analysis Of Convection Heat Transfer

Section: Chapter Questions

Problem 5.69P

See similar textbooks

Similar questions

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.
Air at 20°C, 1 atm flows with a velocity of 4.5 m/s over a flat plate having a sharp leading edge. The plate surface isisothermal at 60°C.(a)Find out the distance from leading edge at which the flow in the boundary layer changes from laminar to turbulent.(b)Using exact solution,determinethe following parameters at the location established at part (a):(i)Thickness of the hydrodynamic boundary layer(ii)Thickness of the thermalboundary layer(iii)Local convective heat transfer coefficient(iv)Average convective heat transfer coefficient(v)Heat transfer rate from both sides per unit width of the plate(vi)Mass entrainment in the boundary layer(vii)The skin friction coefficient
Air at 20°C, 1 atm flows with a velocity of 4.5 m/s over a flat plate having a sharp leading edge. The plate surface isothermal at 60°C. (a)Find out the distance from the leading edge at which the flow in the boundary layer changes from laminar to turbulent. (b)Using the exact solution, determine the following parameters at the location established at part (a): (i)Thickness of the hydrodynamic boundary layer (ii)Thickness of the thermal boundary layer
A thermocouple junction is in the form of 8 mm diameter sphere. Properties of materialare: Cp = 420 J/kg-K; ρ = 8000 kg/m3 ; k = 40 W/m-K; h = 40 W/m2 -K. This junction isinitially at 40 oC and inserted in a stream of hot air at 300 oC. Find the following:a. Time constant of the thermocouple.b. The thermocouple is taken out from the hot air after 10 seconds and kept in still airat 30 oC. Assuming the heat transfer coefficient in air is 10 W/m2-oC, find thetemperature attained by the junction 20 seconds after removal from hot air.
8. A coal fired steam boiler uses 3000 kg of coal per hour. Air required for combustion is 15.5 kg ofcoal at barometric pressure of 98.2 KPa. The flue gas has temperature of 285 degree Celsiusand an average molecular weight of 30. Assuming an ash loss of 11% and allowable gas velocityof 7.5 meters per second. Find the diameter of the chimney 9. The gas density is 0.75 kg per cubic meters and air density is of 1.15 kg per cubic meter. If thedriving pressure is 0.25 KPA. Determine the height of the chimney. 10. A powerplant situated at an altitude having an ambient air of 96.53 KPa and 23.88 degreeCelsius. Flue gases at a rate of 5.0 kg per second enter the stack at 200 degree Celsius andleaves at 160 degree Celsius. The flue gases gravimetric analysis are 18% CO2, 7% O2 and 75%N2. Calculate the height of the stack necessary for a driving pressure of 0.20 KPaKindly answer all please. Thank you
A solid ball is dropped into a water container for cooling. The ball has a diameter of D = 4 mm and sinks at a constant terminal velocity of Ut = 0.01 m/s. The thermophysical properties of the solid ball are: density ρ = 8000 kg/m3, thermal conductivity k = 200 W/m · K, and specific heat c = 1000 J/kg · K. The thermophysical properties of the water are: density ρw = 1000 kg/m3, kinematic viscosity νw = 10^(−6) m^(2)/s, thermal conductivity kw = 0.6 W/m · K, and Prandtl number Pr = 7. The vertical distance for the ball to sink from the initial fully submerged depth to the bottom of the container is H = 0.1 m. The initial temperature of the ball is T0 = 800 K, and the water temperature is T∞ = 300 K.Given correlations: For the convection heat transfer caused by flow past a sphere, the averaged Nusselt number is NuD = 2 + 0.6*(Re^(1/2))*(Pr^(1/3)) Questions:(1) Determine the averaged convection heat transfer coefficient h, and check if the LumpedCapacitance Method can be used to solve…
4.2. The ball catathermometer factor (F) is 620, time while the spirit column drops from 38 to 350C in 100 seconds and the air temperature is 260C. Determine the air movement speed for the industrial section with these parameters.
Consider a thin-walled, ﬁ xed-volume container of volume V that holds an ideal gas at constant temperature T. It can be shown by dimensional analysis that the number of particles striking the walls of the container per unit area per unit time is given by nv-/4, where as usual n is the particle number density. The container has a small hole of area A in its surface through which the gas can leak slowly. Assume that A is much less than the surface area of the container. (a) Assuming that the pressure inside the container is much greater than the outside pressure (so that no gas will leak from the outside back in), estimate the time it will take for the pressure inside to drop to half the initial value. Your answer should contain A, V, and the mean molecular speed v-. (b) Obtain a numerical result for a spherical container with a diameter of 40 cm containing air at 293 K, if there is a circular hole of diameter 1.0 mm in the surface.
In a glass production process, a glass plate of 0.5 m x 2 m and 3 mm thickness is cooled by air blown at a speed of 1 m/s from both sides. Air is blown parallel to the plate. The initial temperature of the glass plate is 425 C and the temperature of the air is 200 C. Calculate the temperature of the plate after cooling for 5 minutes. Properties of glass = 2500 kg/m3, c = 7600 J/kgK, k = 0.8 W/mKproperties of air