460 CHAPTER 8. LABORATORY MEASUREMENT AND ANALYSIS
High-quality, accurate measurements are essential for
conducting successful laboratory studies of fundamental and applied engineering research.
In addition, the reliability of laboratory results often depends on the engineer’s understanding of the physical processes as well as the capabilities
and limitations of laboratory test equipment and instrumentation (Burgi
1987). The challenge for coastal engineers planning laboratory experiments
or model studies (or field experiments for that matter) is knowing
1. What physical parameters must be measured to make a
meaningful interpretation of the physical processes
2. At what location the measurements should be taken
3. What instruments are suitable for making the measurements
4. The accuracy and reliability of the measurements
For field studies it is necessary to add considerations related to instrument
survivability and instrument deployment and retrieval, items that usually
are minor concerns in laboratory studies.
In most hydraulic laboratories, evaluation of new instruments and data
acquisition methods is considered a continuous process that is needed to
assure that modern techniques are used for gathering and analyzing laboratory data. Measurement capability is constantly improving; and each new
capability adds to the utility of laboratory experimentation, often opening
the door on new areas of research. In some instances, developments in
measurement technology have permitted us to measure physical parameters that had never before been measured with any degree of confidence.
For example, the advent of the laser Doppler velocimeter provided an effective and nonintrusive means to measure flow kinematics associated with
turbulence.
Advances in electronic instrumentation have resulted in an increase in
measurement accuracy, and the linking of electronic instruments to computers has dramatically increased the volume and variety of data that can
be collected from hydraulic laboratory experiments (Kamphuis 1991). In
a few short years we have gone from the predicament of often not being
able to obtain enough satisfactory measurements to the point where it is
possible to be inundated with high-quality data.
Computers have also assisted tremendously in the analyses of measured
data. Gone (for the most part) are the days when data records were laboriously analyzed by hand and converted into usable engineering units or
summarized as statistical parameters. These tasks are now done in the
High-quality, accurate measurements are essential for
conducting successful laboratory studies of fundamental and applied engineering research.
In addition, the reliability of laboratory results often depends on the engineer’s understanding of the physical processes as well as the capabilities
and limitations of laboratory test equipment and instrumentation (Burgi
1987). The challenge for coastal engineers planning laboratory experiments
or model studies (or field experiments for that matter) is knowing
1. What physical parameters must be measured to make a
meaningful interpretation of the physical processes
2. At what location the measurements should be taken
3. What instruments are suitable for making the measurements
4. The accuracy and reliability of the measurements
For field studies it is necessary to add considerations related to instrument
survivability and instrument deployment and retrieval, items that usually
are minor concerns in laboratory studies.
In most hydraulic laboratories, evaluation of new instruments and data
acquisition methods is considered a continuous process that is needed to
assure that modern techniques are used for gathering and analyzing laboratory data. Measurement capability is constantly improving; and each new
capability adds to the utility of laboratory experimentation, often opening
the door on new areas of research. In some instances, developments in
measurement technology have permitted us to measure physical parameters that had never before been measured with any degree of confidence.
For example, the advent of the laser Doppler velocimeter provided an effective and nonintrusive means to measure flow kinematics associated with
turbulence.
Advances in electronic instrumentation have resulted in an increase in
measurement accuracy, and the linking of electronic instruments to computers has dramatically increased the volume and variety of data that can
be collected from hydraulic laboratory experiments (Kamphuis 1991). In
a few short years we have gone from the predicament of often not being
able to obtain enough satisfactory measurements to the point where it is
possible to be inundated with high-quality data.
Computers have also assisted tremendously in the analyses of measured
data. Gone (for the most part) are the days when data records were laboriously analyzed by hand and converted into usable engineering units or
summarized as statistical parameters. These tasks are now done in the