464 CHAPTER 8. LABORATORY MEASUREMENT AND ANALYSIS
— Sediment fall speed
— Vibration
• Other Environmental Measurements include those
measurements not covered by the first four categories, such
as:
- Atmospheric pressure
- Air temperature
- Air humidity
- Wind speed
- Time (when recorded in conjunction with experiment
duration, movable-bed evolution, etc.)
In addition to the experiment characteristics that we measure directly,
we can also analyze various measurements to get other parameters that are
not so easily measured. Examples include significant wave height, wave
transmission and reflection, and wave spectra. Even though we may refer
to these analyzed results as “measurements,” in many cases the analysis
may involve additional simplifying assumptions, and the results are more
aptly described as “estimates.”
Most “Fluid Motion” and “Force and Transport” measurements are
obtained at a point in the fluid regime. In many cases, data are collected at
equally-spaced time increments to give a time series record at that point.
If we want a spatial description of the flow field, multiple instruments or
repeated experiments are necessary. Visual and remote sensing techniques
are available to acquire “snapshots” of the flow field at a point in time.
8.1.3 Selection of Instruments
Successful laboratory studies depend on selecting appropriate instrumentation to acquire the necessary measurements. Conversely, attempting measurements with inadequate instruments may compromise the experiment or
cast doubt on the results. Therefore, it stands to reason that most coastal
engineering laboratory studies will benefit when the investigator has good
knowledge of available instruments and their capabilities and limitations.
Planning for instrumentation should occur during the experiment design
stages. This is particularly important if instruments need to be embedded
in the model itself, such as pressure transducers or strain gauges. By determining instrument needs early in the planning, there will be ample time
for servicing, calibrating, and testing the instruments before they are used
in the experiment. If new or unfamiliar instruments are to be used, time
— Sediment fall speed
— Vibration
• Other Environmental Measurements include those
measurements not covered by the first four categories, such
as:
- Atmospheric pressure
- Air temperature
- Air humidity
- Wind speed
- Time (when recorded in conjunction with experiment
duration, movable-bed evolution, etc.)
In addition to the experiment characteristics that we measure directly,
we can also analyze various measurements to get other parameters that are
not so easily measured. Examples include significant wave height, wave
transmission and reflection, and wave spectra. Even though we may refer
to these analyzed results as “measurements,” in many cases the analysis
may involve additional simplifying assumptions, and the results are more
aptly described as “estimates.”
Most “Fluid Motion” and “Force and Transport” measurements are
obtained at a point in the fluid regime. In many cases, data are collected at
equally-spaced time increments to give a time series record at that point.
If we want a spatial description of the flow field, multiple instruments or
repeated experiments are necessary. Visual and remote sensing techniques
are available to acquire “snapshots” of the flow field at a point in time.
8.1.3 Selection of Instruments
Successful laboratory studies depend on selecting appropriate instrumentation to acquire the necessary measurements. Conversely, attempting measurements with inadequate instruments may compromise the experiment or
cast doubt on the results. Therefore, it stands to reason that most coastal
engineering laboratory studies will benefit when the investigator has good
knowledge of available instruments and their capabilities and limitations.
Planning for instrumentation should occur during the experiment design
stages. This is particularly important if instruments need to be embedded
in the model itself, such as pressure transducers or strain gauges. By determining instrument needs early in the planning, there will be ample time
for servicing, calibrating, and testing the instruments before they are used
in the experiment. If new or unfamiliar instruments are to be used, time