6. Consider a plate solar collector placed horizontally on theflat roof of a house. The collector measures 1.5 m wide and4.5 m long, and the average temperature of the exposedsurface of the collector is 38°C. The emissivity of the exposedsurface of the collector is 0.9. Determine the rate of heatloss of the collector during a calm day, when the ambient airtemperature is 20°C and the effective temperature of thesky, for exchange for radiation is 10°C. Consider theconvection heat transfer coefficient of the exposed surfacequal to 14 W/m^2.K 1. A small gray sphere, with an emissivity coefficient of 0.5 anda surface temperature of 537°C, is located in a black bodywrap with a temperature of 35°C. For this system, calculatethe net rate of heat transfer per unit of surface area of thesphere.2. Gaseous oxygen is maintained at pressures of 2 atm and 1atm on the opposite sides of a rubber membrane, which hasa thickness of 0.5 mm, and the entire system is at25°C. What is the diffusive mass flow of gas through themembrane?DAB=0.21x10^-9 m^2/s; O = 16 g/mol3. Pure oxygen gas at 2 bar and 25°C is flowing through arubber hose of 10 m long, with 40 mm internal diameter and2 mm wall thickness. The external surface is exposed to anair stream in which the partial pressure of the gas is 0.1 bar.The diffusivity and solubility of the gas in the hose materialare 0.21x10^-9 m^2/s and 3.12x10^-3 kmol/m^3.bar.respectively. Determine the mass rate at which the gas leaksout of the hose.4. Consider the diffusion of gaseous hydrogen into iron, at T =293 K. Calculate the flow of the species if the concentrationgradient at a specific location is equal to dCa/dx=-1kmol/m^3.m.5. The wing of an airplane has a polished aluminum coating. Atan altitude of 1500 m (T = 5°C), does it absorb 100 W/m^2Of heat by solar radiation. Assuming that the inner surfaceof the wing lining is well insulated and that it has a rope of6m (that is, L = 6m), calculate the equilibrium temperatureof the wing at a speed of 150 m/s for a distance of x m fromthe front edge, where the convective coefficient is hx = 222W/m^2.K

Given Data: b=1.5 mL=4.5 mTc=38oCε=0.9T∞=20oCTs=10oCh=14 W/m2K To Find: The rate of heat loss of…

Consider a plate solar collector placed horizontally on the flat roof of a house. The collector measures 1.5 m wide and 4.5 m long, and the average temperature of the exposed surface of the collector is 38°C. The emissivity of the exposed surface of the collector is 0.9. Determine the rate of heat loss of the collector during a calm day, when the ambient air temperature is 20°C and the effective temperature of the sky, for exchange for radiation is 10°C. Consider the convection heat transfer coefficient of the exposed surface qual to 14 W/m^2.K

Consider a plate solar collector placed horizontally on the flat roof of a house. The collector measures 1.5 m wide and 4.5 m long, and the average temperature of the exposed surface of the collector is 38°C. The emissivity of the exposed surface of the collector is 0.9. Determine the rate of heat loss of the collector during a calm day, when the ambient air temperature is 20°C and the effective temperature of the sky, for exchange for radiation is 10°C. Consider the convection heat transfer coefficient of the exposed surface qual to 14 W/m^2.K

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.

Chapter1: Basic Modes Of Heat Transfer

Section: Chapter Questions

Problem 1.30P

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Similar questions

1.28 The sun has a radius of and approximates a blackbody with a surface temperature of about 5800 K. Calculate the total rate of radiation from the sun and the emitted radiation flux per square meter of surface area.
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