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 8.33P
An iron-constantan thermocouple is placed in a moving air stream in a duct, as shown in Figure 8.48. The thermocouple reference junction is maintained at 212 °F. The wall temperature, Tw>is 500 °F, and the air velocity is 200 ft/s. The output voltage from the thermocouple is 14.143 mV.
Figure 8.48 Schematic diagram for Problems 8.33, 34, and 35.
- 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 70 Btu/hr-ff-°F.
| Air Properties | Thermocouple Properties |
| Cp = 0.24 Btu/lbm°F | r = 0.7 |
| U = 200 ft/s | e = 0.25 |
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Chapter 8 Solutions
Theory and Design for Mechanical Measurements
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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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