4400 Exam 3 solution

# 4400 Exam 3 solution - MEAE 4400 NAME:_ Problem 1. (5...

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MEAE 4400 Exam 3 5/1/2007 NOTE: (i) Show all the “in-between” steps, results and parameters used 1 NAME:_____________________________ Problem 1. (5 points) Using a SCR, you have reduced the power supplied to the 100 W light bulb to 50 W. As a result, the temperature of the filament is reduced from 3000 to 2300 C. Determine the % of a) visible and b) IR light transmitted is through the glass. -------------- a) Visible T = 2573 [K] λ 1 = 0.4 [μm] λ 2 = 0.7 [μm] E b = 2.485E+06 [W/m 2 ] Total blackbody emissive power = Fraction between λ 1 and λ 2 = f 1,2 = 0.03904 Absolute temperature = Low wavelength = High wavelength = Note : to account for reflectivity, multiply f1,2 by 0.9 or 0.95. b) IR T = 2573 [K] λ 1 = 0.7 [μm] λ 2 = 2.5 [μm] E b = 2.485E+06 [W/m 2 ] Total blackbody emissive power = Fraction between λ 1 and λ 2 = f 1,2 = 0.7322 Absolute temperature = Low wavelength = High wavelength = Note : to account for reflectivity, multiply f1,2 by 0.9 or 0.95.

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MEAE 4400 Exam 3 5/1/2007 NOTE: (i) Show all the “in-between” steps, results and parameters used 2 Problem 2. (4 points) 2. Calculate the heat flux between the two pipes shown in Fig. 1. if T
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## This note was uploaded on 04/28/2008 for the course MANE 4400 taught by Professor Ostrogorsky during the Spring '07 term at Rensselaer Polytechnic Institute.

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4400 Exam 3 solution - MEAE 4400 NAME:_ Problem 1. (5...

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