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 8.34P
Figure 8.48 Schematic diagram for Problems 8.33, 34, and 35.
8.34 An iron-constantan thermocouple is placed in a moving air stream in a duct, as shown in Figure 8.48. The air flows at 70 m/s. The emissivity of the thermocouple is 0.5 and the recovery factor is 0.6. The wall temperature, Twis 300 °C. The thermocouple reference junction is maintained at 100 °C. The emf output from the thermocouple is 16 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 100 W/m2K.
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Chapter 8 Solutions
Theory and Design for Mechanical Measurements
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