Theory and Design for Mechanical Measurements
6th Edition
ISBN: 9781118881279
Author: Richard S. Figliola, Donald E. Beasley
Publisher: WILEY
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Chapter 8, Problem 8.35P
Figure 8.48 Schematic diagram for Problems 8.33, 34, and 35.
8.35 An iron-constantan thermocouple is placed in a moving air stream in a duct, as shown in Figure 8.48. The air flows at 180 ft/sec. The emissivity of the thermocouple is 0.7 and the recovery factor is 0.7. The wall temperature, Twis 500 °F. The thermocouple reference junction is maintained at 32 °F. The emf output from the thermocouple is 20 mV.
- Determine the thermocouple junction temperature.
- By considering recovery and radiation errors, estimate the possible value for total error in the indicated temperature. Discuss whether this estimate of the measurement error is conservative and why, or why not. The heat-transfer coefficient may be taken as 40 Btu/hr-ft °F, and the specific heat as cp= 0.24 Btu/lbm°F.
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Chapter 8 Solutions
Theory and Design for Mechanical Measurements
Ch. 8 - Prob. 8.1PCh. 8 - Fixed temperature points in the International...Ch. 8 - Answers to the following questions may be found in...Ch. 8 - Calculate the resistance of a platinum wire that...Ch. 8 - Plot the resistance of a platinum wire that is 5 m...Ch. 8 - An RTD forms one arm of a Wheatstone bridge, as...Ch. 8 - An RTD forms one arm (/?4) of a Wheatstone bridge,...Ch. 8 - Research and describe current state-of-the-art...Ch. 8 - Prob. 8.9PCh. 8 - 8.10 Estimate the required level of uncertainty in...
Ch. 8 - 8.11 A thermistor is placed in a 100 °C...Ch. 8 - Prob. 8.12PCh. 8 - Prob. 8.13PCh. 8 - The thermocouple circuit in Figure 8.45 represents...Ch. 8 - The thermocouple circuit in Figure 8.45 represents...Ch. 8 - The thermocouple circuit in Figure 8.45 is...Ch. 8 - 8.17 a. The thermocouple shown in Figure 8.46a...Ch. 8 - Prob. 8.18PCh. 8 - Prob. 8.19PCh. 8 - A temperature measurement requires an uncertainty...Ch. 8 - A temperature difference of 3.0 °C is measured...Ch. 8 - Complete the following table for a J-type...Ch. 8 - Complete the following table for a T-type...Ch. 8 - Prob. 8.24PCh. 8 - 8.25 You are employed as a heating, ventilating,...Ch. 8 - A J-type thermocouple for use at temperatures...Ch. 8 - A J-type thermocouple is calibrated against an RTD...Ch. 8 - A beaded thermocouple is placed in a duct in a...Ch. 8 - Consider a welded thermocouple bead that...Ch. 8 - Prob. 8.30PCh. 8 - Prob. 8.31PCh. 8 - Consider the typical construction of a sheathed...Ch. 8 - An iron-constantan thermocouple is placed in a...Ch. 8 - Figure 8.48 Schematic diagram for Problems 8.33,...Ch. 8 - Figure 8.48 Schematic diagram for Problems 8.33,...Ch. 8 - 8.36 In Example 8.5, an uncertainty value for Rf...Ch. 8 - The thermocouple circuit shown in Figure 8.49...Ch. 8 - Prob. 8.38PCh. 8 - 8.39 A thin-film heat flux sensor employs a K-type...Ch. 8 - A thin-film heat flux sensor has a sensitivity uV...Ch. 8 - 8.41 A T-type thermopile is used to measure...Ch. 8 - 8.42 A T-type thermocouple referenced to 0 °C is...Ch. 8 - A T-type thermocouple referenced to 0 °C develops...Ch. 8 - 8.44 A temperature measurement system consists of...
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