Instrumentation for Engineering Measurements, 2nd Edition

by James W. Dally (Univ. of Maryland); William F. Riley (Iowa State Univ.); Kenneth G. McConnell (Iowa State Univ.)

• ISBN13: 9780471551928
• ISBN10: 0471551929
• Edition: 2nd
• Format: Hardcover
• Copyright: 1993-02-01
• Publisher: Wiley

Summary

Stressing electronic measurements, this edition deals in considerable detail with the many aspects of digital instrumentation currently used in industry for engineering measurements and process control. New features include equipment used to manage different procedures, electronic and electrical principles important in understanding instrument systems operations, detailed descriptions of analog-to-digital and digital-to-analog conversions, characterization of signals and the processing of vibration data with a digital frequency analyzer.

Table of Contents

List of Symbols	xvii
Applications of Electronic Instrument Systems	1	(23)
Introduction	1	(1)
The Electronic Instrument System	2	(1)
Engineering Analysis	3	(1)
Process Control	4	(8)
Process Control Devices	6	(6)
Experimental Error	12	(7)
Accumulation of Accepted Error	13	(1)
Improper Functioning of Instruments	14	(1)
Effect of the Transducer on the Process	15	(2)
Dual Sensitivity Errors	17	(1)
Other Sources of Error	18	(1)
Minimizing Experimental Error	19	(1)
Summary	20	(4)
References	20	(1)
Exercises	21	(3)
Analysis of Circuits	24	(25)
Introduction and Definitions	24	(2)
Basic Electrical Components	26	(2)
Kirchhoff's Circuit Laws	28	(1)
Diodes, Transistors, and Gates	29	(4)
Diodes	29	(1)
Transistors	29	(2)
Gates	31	(2)
DC Circuits	33	(1)
Periodic Functions	34	(4)
AC Circuits	38	(4)
Impedance	40	(2)
Frequency Response Function	42	(2)
Summary	44	(5)
References	45	(1)
Exercises	45	(4)
Analog Recording Instruments	49	(37)
Introduction	49	(1)
General Characteristics of Recording Instruments	49	(5)
Voltmeters for Steady-State Measurements	54	(5)
D'Arsonval Galvanometer	54	(1)
Ammeter	55	(1)
DC Voltmeters	56	(1)
Voltmeter Loading Errors	57	(1)
Amplified Voltmeters	57	(1)
Potentiometric Voltmeters	58	(1)
Voltmeters for Slowly Varying Signals	59	(2)
Strip-Chart Recorders	59	(1)
X-Y Recorders	60	(1)
Voltmeters for Rapidly Varying Signals	61	(20)
Oscillograph Recorders	61	(1)
Transient Response of Galvanometers	62	(6)
Periodic Signal Response of Galvanometers	68	(5)
Oscilloscopes	73	(4)
Magnetic Tape Recorders	77	(4)
Summary	81	(5)
References	82	(1)
Exercises	82	(4)
Digital Recording Systems	86	(38)
Introduction	86	(1)
Digital Codes	86	(2)
Conversion Processes	88	(1)
Digital-to-Analog Converters	89	(3)
Analog-to-Digital Converters	92	(6)
Successive-Approximation Method	92	(2)
Intergration Method	94	(3)
Parallel or Flash Method	97	(1)
Data Distribution	98	(3)
Bus Structures	99	(2)
Interfaces	101	(1)
Digital Voltmeters	102	(6)
Data-Logging Systems	108	(1)
Data-Acquisition Systems	109	(3)
PC-Based Data-Acquisition Systems	112	(1)
Digital Oscilloscopes	112	(4)
Waveform Recorders	116	(1)
Aliasing	117	(2)
Antialiasing Filters	119	(1)
Summary	119	(5)
References	120	(1)
Exercises	120	(4)
Sensors for Transducers	124	(38)
Introduction	124	(1)
Potentiometers	124	(2)
Differential Transformers	126	(3)
Resistance Strain Gages	129	(6)
Capacitance Sensors	135	(2)
Eddy-Current Sensors	137	(2)
Piezoelectric Sensors	139	(3)
Piezoresistive Sensors	142	(2)
Photoelectric Sensors	144	(7)
Vacuum-Tube Detectors	146	(3)
Photoconductive Cells	149	(1)
Semiconductor Photodiodes	149	(2)
Resistance Temperature Detectors	151	(1)
Thermistors	152	(1)
Thermocouples	153	(2)
Crystal Oscillators	155	(2)
Summary	157	(5)
References	157	(1)
Exercises	158	(4)
Signal Conditioning Circuits	162	(49)
Introduction	162	(1)
Power Supplies	162	(4)
Battery Supplies	162	(3)
Line Voltage Supplies	165	(1)
Potentiometer Circuit (Constant Voltage)	166	(3)
Potentiometer Circuit (Constant Current)	169	(1)
Wheatstone Bridge (Constant Voltage)	170	(3)
Wheatstone Bridge (Constant Current)	173	(3)
Amplifiers	176	(5)
Operational Amplifiers	181	(8)
Inverting Amplifier	181	(3)
Differential Amplifier	184	(2)
Voltage Follower	186	(1)
Summing Amplifier	187	(1)
Integrating Amplifier	188	(1)
Differentiating Amplifier	189	(1)
Filters	189	(5)
High-Pass RC Filter	190	(1)
Low-Pass RC Filter	191	(2)
Active Filter	193	(1)
Amplitude Modulation and Demodulation	194	(3)
Time-Measuring Circuits	197	(5)
Binary Counting Unit	197	(1)
Gates in Counter Applications	198	(1)
Triggers	198	(1)
Counting Instruments	199	(3)
Summary	202	(9)
References	205	(1)
Exercises	206	(5)
Resistance-Type Strain Gages	211	(42)
Introduction	211	(1)
Etched-Foil Strain Gages	212	(1)
Strain-Gage Installation	212	(2)
Wheatstone Bridge Signal Conditioning	214	(5)
Recording Instruments for Strain Gages	219	(8)
Direct-Reading Strain Indicator	220	(1)
Null-Balance Bridges	220	(2)
Strain-Gage Signal Conditioners	222	(1)
Wheatstone Bridge and Oscilloscope	222	(2)
Wheatstone Bridge and Oscillograph	224	(3)
Calibration Methods	227	(2)
Effects of Lead Wires, Switches, and Slip Rings	229	(5)
Lead Wires	229	(3)
Switches	232	(2)
Slip Rings	234	(1)
Electrical Noise	234	(2)
Temperature-Compensated Gages	236	(2)
Alloy Sensitivity, Gage Factor, and Cross-Sensitivity Factors	238	(3)
Data-Reduction Methods	241	(3)
The Uniaxial State of Stress	241	(1)
The Biaxial State of Stress	242	(1)
The General State of Stress	242	(2)
High-Temperature Strain Measurements	244	(1)
Summary	245	(8)
References	248	(1)
Exercises	249	(4)
Force, Torque, and Pressure Measurements	253	(40)
Introduction	253	(1)
Force Measurements (Load Cells)	253	(9)
Link-Type Load Cell	254	(2)
Beam-Type Load Cell	256	(2)
Ring-Type Load Cell	258	(2)
Shear-Web-Type Load Cell	260	(2)
Torque Measurement (Torque Cells)	262	(6)
Torque Cells---Design Concepts	262	(2)
Torque Cells---Data Transmission	264	(4)
Combined Measurements of Force and Moments or Torques	268	(3)
Force-Moment Measurements	268	(3)
Force-Torque Measurements	271	(1)
Pressure Measurements (Pressure Transducers)	271	(5)
Displacement-Type Pressure Transducer	272	(1)
Diaphragm-Type Pressure Transducer	272	(3)
Piezoelectric-Type Pressure Transducer	275	(1)
Minimizing Errors in Transducers	276	(4)
Dual Sensitivity	277	(2)
Zero Shift with Temperature Change	279	(1)
Bridge Balance	280	(1)
Span Adjust	280	(1)
Span Change with Temperature	280	(1)
Frequency Response of Transducers	280	(6)
Response of a Force Transducer to a Terminated Ramp Function	282	(3)
Response of a Force Transducer to a Sinusoidal Forcing Function	285	(1)
Calibration of Transducers	286	(2)
Summary	288	(5)
References	289	(1)
Exercises	290	(3)
Displacement, Velocity, and Acceleration Measurements	293	(63)
Introduction	293	(1)
The Seismic Transducer Model	294	(1)
Dynamic Response of the Seismic Model	295	(4)
Sinusoidal Excitation	295	(3)
Transient Excitations	298	(1)
Seismic Motion Transducers	299	(6)
Seismic Displacement Transducers	300	(1)
Seismic Velocity Transducers	301	(1)
Seismic Acceleration Transducers	301	(4)
Piezoelectric Force Transducers	305	(1)
Piezoelectric Sensor Circuits	306	(11)
Charge Sensitivity Model	306	(2)
Voltage-Follower Circuit	308	(3)
Charge-Amplifier Circuit	311	(2)
Built-In Voltage Followers	313	(4)
Response of Piezoelectric Circuits to Transient Signals	317	(3)
Accelerometer Calibration	320	(3)
Dynamic Calibration of Force Transducers	323	(4)
Force Transducer Calibration by Impact	325	(2)
Overall System Calibration	327	(1)
Sources of Error with Piezoelectric Transducers	328	(3)
Displacement Measurements in a Fixed Reference Frame	331	(6)
Displacement Measurements with Resistance Potentiometers	331	(4)
Displacement Measurements with Multiple-Resistor Devices	335	(1)
Photoelectric Displacement Transducers	336	(1)
Optical Displacement Measurements	337	(2)
Optical Tracker System	337	(1)
Video Camera Motion Analysis	338	(1)
Velocity Measurements	339	(5)
Linear-Velocity Measurements	340	(2)
Angular-Velocity Measurements	342	(1)
Laser-Doppler System	343	(1)
Summary	344	(12)
References	345	(2)
Exercises	347	(9)
Analysis of Vibrating Systems	356	(56)
Introduction	356	(2)
Temporal Mean	358	(1)
Temporal Mean Square and Root Mean Square	358	(1)
Sinusoidal Signal Analysis	358	(3)
Characteristics of Signals	361	(7)
Periodic Signals	362	(1)
Transient Signals	363	(3)
Random Signals	366	(2)
Lumped Mass-Spring Vibration Models	368	(5)
Undamped Natural Frequency and Mode Shape	369	(1)
Forced Vibration Response (Direct Solution)	370	(1)
Forced Vibration Response (Model Solution)	370	(3)
Continuous Vibration Models	373	(3)
Fundamental Equation of Motion	373	(1)
Steady-State Modal Solution	374	(2)
The Linear Input-Output Model	376	(4)
Impulse Response	377	(2)
Random Input-Output Relationships	379	(1)
Basics of a Digital Frequency Analyzer	380	(7)
Time Sampling Process	380	(1)
Convolution	381	(4)
Filter Leakage	385	(2)
Block Diagram	387	(1)
Using a Digital Frequency Analyzer	387	(9)
Relationship for Frequency Analyzers	388	(2)
Filter Characteristics	390	(2)
Four Common Window Functions	392	(2)
Uncertainty in the Magnitude of Spectral Lines	394	(1)
Summary of Window Use	395	(1)
Accelerometer Cross-Axis Sensitivity	396	(4)
Single Accelerometer Cross-Axis Coupling Model	396	(1)
Triaxial Accelerometer Model	397	(1)
Correcting Acceleration Voltage Readings	397	(2)
Application to Modal Analysis Signals	399	(1)
Cross-Axis Resonance	399	(1)
Force Transducer-Structure Interaction	400	(6)
General Two-Degree-of-Freedom Force Transducer Model	401	(5)
Summary	406	(6)
References	408	(1)
Exercises	409	(3)
Temperature Measurements	412	(61)
Introduction	412	(3)
Expansion Methods for Measuring Temperature	415	(1)
Resistance Thermometers	416	(12)
Resistance Temperature Detectors (RTDS)	417	(3)
RTDS and the Wheatstone Bridge	420	(4)
Thermistors	424	(4)
Thermocouples	428	(16)
Principles of Thermocouple Behavior	430	(4)
Thermoelectric Materials	434	(3)
Reference Junction Temperature	437	(2)
Fabrication and Installation Procedures	439	(3)
Recording Instruments for Thermocouples	442	(2)
Noise Suppression in Thermocouple Circuits	444	(1)
Integrated-Circuit Temperature Sensors	444	(2)
Dynamic Response of Temperature Sensors	446	(3)
Sources of Error in Temperature Measurements	449	(4)
Calibration Methods	453	(1)
Radiation Methods (Pyrometry)	454	(9)
Principles of Radiation	454	(2)
The Optical Pyrometer	456	(2)
Infrared Pyrometers	458	(2)
Photon Detector Temperature Instruments	460	(3)
Summary	463	(10)
References	465	(1)
Exercises	466	(7)
Fluid Flow Measurements	473	(48)
Introduction	473	(3)
Flow Velocity (Insertion-Type Transducers)	476	(17)
Pitot Tube (Incompressible Flow)	476	(3)
Pitot Tube (Compressible Flow)	479	(2)
Hot-Wire and Hot-Film Anemometers	481	(5)
Drag-Force Velocity Transducers	486	(3)
Current Meters	489	(2)
Turbine Flow Meters	491	(1)
Vortex-Shedding Transducers	492	(1)
Flow Rates in Closed Systems by Pressure-Variation Measurements	493	(6)
Venturi Meter	494	(1)
Flow Nozzle	495	(1)
Orifice Meter	496	(2)
Elbow Meter	498	(1)
Flow Rates in Partially Closed Systems	499	(1)
Flow Rates in Open Channels from Pressure Measurements	500	(3)
Sluice Gate	500	(1)
Weirs	501	(2)
Compressible Flow Effects in Closed Systems	503	(1)
Other Flow-Measurement Methods for Closed Systems	504	(8)
Capillary Flow Meter	504	(1)
Positive-Displacement Flow Meters	505	(1)
Hot-Film Mass Flow Transducers	506	(1)
Laser Velocimetry Systems	507	(5)
Summary	512	(9)
References	512	(2)
Exercises	514	(7)
Statistical Methods	521	(37)
Introduction	521	(1)
Characterizing Statistical Distributions	522	(4)
Graphic Representations of the Distribution	522	(2)
Measures of Central Tendency	524	(1)
Measures of Dispersion	524	(2)
Statistical Distribution Functions	526	(6)
Gaussian Distribution	526	(3)
Weibull Distribution	529	(3)
Confidence Intervals for Predictions	532	(5)
Comparision of Means	537	(1)
Statistical Conditioning of Data	537	(1)
Regression Analysis	538	(6)
Linear Regression Analysis	539	(2)
Multivariate Regression	541	(3)
Chi-Square Testing	544	(1)
Error Accumulation and Propagation	545	(3)
Summary	548	(10)
References	549	(1)
Exercises	550	(8)
Appendix A	558	(14)
Appendix B	572	(5)
Author Index	577	(2)
Subject Index	579