Difference between revisions of "USD-49 depth-integrating sampler"

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==USD-49 depth-integrating sampler==
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This article is a summary of sub-section 5.6.2.6 of the [[Manual Sediment Transport Measurements in Rivers, Estuaries and Coastal Seas]]<ref>Rijn, L. C. van (1986). ''Manual sediment transport measurements''. Delft, The Netherlands: Delft Hydraulics Laboratory</ref>. This article describes how the suspended load can be measured with a USD-49 sampler. This sampler is, just as the [[Collapsible-Bag depth-integrating sampler]] an example of a depth-integrating sampler.
  
The USD-49 is a depth integrating sampler. The sampler is lowered at a uniform rate from the water surface to the streambed, instantly reversed, and then raised again to the water surface. The sampler continues to take its sample throughout the time of submergence. At least one sample should be taken at each vertical selected in the cross-section of the stream. A clean bottle is used for each sample. The USD-49 sampler has a cast bronze streamlined body in which a round or square pint-bottle sample container is enclosed. The head of the sampler is hinged to permit access to the sample container (see Figure 1). The head of the sampler is drilled and tapped to receive the ¼-inch, 3/16-inch or 1/8-inch intake nozzle which points into the current for collecting the sample. The transit rate depends on the mean velocity in the vertical, the water depth and the nozzle diameter, as shown in Figure 2. The USD-49 is suitable for depth integration of streams less than about 5 m in which the velocities do not exceed 2 m/s.
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==Introduction==
The sampler is manufactured by Rickly Hydrological company (www.rickly.com).
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[[Image:H5626figure1.jpg|thumb|250px||right|Figure 1: USD-49 sampler]]
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[[Image:H5626figure2.jpg|thumb|250px|right|Figure 2: Transit rate curve]]
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The USD-49 is a depth integrating sampler. The sampler is lowered at a uniform rate from the water surface to the streambed, instantly reversed, and then raised again to the water surface. The sampler continues to take its sample throughout the time of submergence. At least one sample should be taken at each vertical selected in the cross-section of the stream. A clean bottle is used for each sample. The USD-49 sampler has a cast bronze streamlined body in which a round or square pint-bottle sample container is enclosed. The head of the sampler is hinged to permit access to the sample container (see Figure 1). The head of the sampler is drilled and tapped to receive the ¼-inch, 3/16-inch or 1/8-inch intake nozzle which points into the current for collecting the sample. The transit rate depends on the mean velocity in the vertical, the water depth and the nozzle diameter, as shown in Figure 2. The USD-49 is suitable for depth [integration of streams less than about 5 m in which the velocities do not exceed 2 m/s.
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The sampler is manufactured by [http://www.rickly.com Rickly Hydrological company].
  
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==Determination of the suspended sediment transport==
 
The depth-averaged concentration can be determined as
 
The depth-averaged concentration can be determined as
  
c=G/V
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<math>c\,=G\,/V\,</math>
 
 
in which: G= dry mass of sediment (mg), V= volume of water sample (l).
 
 
 
The depth-integrated suspended sediment transport (in kg/m/s) can be determined as:
 
 
 
S= G h/(F T)    or as    S=c u h= (G/V) u h
 
 
 
in which: G= dry mass of sediment (mg), V= volume of sediment sample, including pores (m<sup>3</sup>),h= depth of sampled zone (m), u= depth-averaged velocity (m/s), F= area of nozzle (m<sup>2</sup>), T= sampling period (s).
 
 
 
The sampler cannot sample down to the stream bed surface. When the sampler touches the bed, the distance between the sample nozzle and the bed is about 0.1 m (see Figure 1). Thus, the depth of the sampled zone is about equal to the water depth minus 0.1 m. Another problem is the short sampling period at each specific point in the vertical. As a result concentration fluctuations are not averaged out and repeat samples are necessary.
 
 
 
==Photographs and Figures==
 
 
 
[[Image:H5626figure1.jpg|thumb|left|Fig. 1: USD-49 sampler]]
 
[[Image:H5626figure2.jpg|thumb|left|Fig. 2: Transit rate curve]]
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  
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in which: <math>G</math>= dry mass of sediment (mg), <math>V</math>= volume of water sample (l).
  
 +
The depth-integrated [[suspended load|suspended]] sediment transport (in kg/m/s) can be determined as:
  
 +
<math>S = \large\frac{Gh}{FT}</math> or as <math>S = c\,u\,h\, = \large\frac{G}{V}\normalsize u\,h</math>
  
 +
in which: <math>G</math>= dry mass of sediment (mg), <math>V</math>= volume of sediment sample, including pores (m<sup>3</sup>),<math>h</math>= depth of sampled zone (m), <math>u</math>= depth-averaged velocity (m/s), <math>F</math>= area of nozzle (m<sup>2</sup>), <math>T</math>= sampling period (s).
  
 +
The sampler cannot sample down to the stream bed surface. When the sampler touches the bed, the distance between the sample nozzle and the bed is about 0.1 m (see Figure 1). Thus, the depth of the sampled zone is about equal to the water depth minus 0.1 m. Another problem is the short sampling period at each specific point in the vertical. As a result concentration fluctuations are not averaged out and repeat samples are necessary.
  
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==See also==
 +
===Summaries of the manual===
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* [[Manual Sediment Transport Measurements in Rivers, Estuaries and Coastal Seas]]
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* Chapter 1: [[Introduction, problems and approaches in sediment transport measurements]]
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* Chapter 2:  [[Definitions, processes and models in morphology]]
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* Chapter 3: [[Principles, statistics and errors of measuring sediment transport]]
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* Chapter 4: [[Computation of sediment transport and presentation of results]]
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* Chapter 5: [[Measuring instruments for sediment transport]]
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* Chapter 6: [[Measuring instruments for particle size and fall velocity]]
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* Chapter 7: [[Measuring instruments for bed material sampling]]
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* Chapter 8: [[Laboratory and in situ analysis of samples]]
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* Chapter 9: [[In situ measurement of wet bulk density]]
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* Chapter 10: [[Instruments for bed level detection]]
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* Chapter 11: [[Argus video]]
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* Chapter 12: [[Measuring instruments for fluid velocity, pressure and wave height]]
  
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===Other internal links===
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* [[Bottle and trap samplers]]
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* [[Collapsible-Bag depth-integrating sampler]]
  
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===External links===
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* [http://www.rickly.com www.rickly.com]
  
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===Further reading===
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INTER-AGENCY COMMITTEE on Water Resources (1963) ''Determination of Fluvial Sediment Discharge Report no. 14'',  St.  Anthony Falls Hydr.  Lab., Minneapolis, USA.
  
 
==References==
 
==References==
 
'''INTER-AGENCY COMMITTEE on Water Resources,  1963'''. Determination of Fluvial Sediment Discharge Report no.  14,  St.  Anthony Falls Hydr.  Lab., Minneapolis, USA.
 
 
 
<references/>
 
<references/>
 
==See also==
 
 
===Other contributions of Leo van Rijn===
 
 
====articles with parts of the manual====
 
*[[Manual Sediment Transport Measurements in Rivers, Estuaries and Coastal Seas]]
 
 
*[[INTRODUCTION, PROBLEMS AND APPROACHES IN SEDIMENT TRANSPORT MEASUREMENTS]]
 
*[[DEFINITIONS, PROCESSES AND MODELS IN MORPHOLOGY]]
 
*[[PRINCIPLES, STATISTICS AND ERRORS OF MEASURING SEDIMENT TRANSPORT]]
 
*[[COMPUTATION OF SEDIMENT TRANSPORT AND PRESENTATION OF RESULTS]]
 
*[[MEASURING INSTRUMENTS FOR SEDIMENT TRANSPORT]]
 
*[[MEASURING INSTRUMENTS FOR PARTICLE SIZE AND FALL VELOCITY]]
 
*[[MEASURING INSTRUMENTS FOR BED MATERIAL SAMPLING]]
 
*[[LABORATORY AND IN-SITU ANALYSIS OF SAMPLES]]
 
*[[IN-SITU MEASUREMENT OF WET BULK DENSITY]]
 
*[[INSTRUMENTS FOR BED LEVEL DETECTION]]
 
*[[ARGUS VIDEO]]
 
*[[MEASURING  INSTRUMENTS FOR FLUID VELOCITY, PRESSURE AND WAVE HEIGHT]]
 
 
 
==External links==
 
 
www.rickly.com([http://www.rickly.com]).
 
 
 
 
==Crediting the authors==
 
 
  
 
{{author  
 
{{author  
 
|AuthorID=13226  
 
|AuthorID=13226  
|AuthorName= Rijn, Leo van}}
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|AuthorFullName= Rijn, Leo van
 
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|AuthorName=Leovanrijn}}
  
 
{{author  
 
{{author  
 
|AuthorID=12969  
 
|AuthorID=12969  
|AuthorName= Roberti, Hans}}
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|AuthorFullName= Roberti, Hans
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|AuthorName=Robertihans}}
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[[Category:Coastal and marine observation and monitoring]]
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[[Category:Observation of physical parameters]]

Latest revision as of 14:19, 22 August 2020

This article is a summary of sub-section 5.6.2.6 of the Manual Sediment Transport Measurements in Rivers, Estuaries and Coastal Seas[1]. This article describes how the suspended load can be measured with a USD-49 sampler. This sampler is, just as the Collapsible-Bag depth-integrating sampler an example of a depth-integrating sampler.

Introduction

Figure 1: USD-49 sampler
Figure 2: Transit rate curve

The USD-49 is a depth integrating sampler. The sampler is lowered at a uniform rate from the water surface to the streambed, instantly reversed, and then raised again to the water surface. The sampler continues to take its sample throughout the time of submergence. At least one sample should be taken at each vertical selected in the cross-section of the stream. A clean bottle is used for each sample. The USD-49 sampler has a cast bronze streamlined body in which a round or square pint-bottle sample container is enclosed. The head of the sampler is hinged to permit access to the sample container (see Figure 1). The head of the sampler is drilled and tapped to receive the ¼-inch, 3/16-inch or 1/8-inch intake nozzle which points into the current for collecting the sample. The transit rate depends on the mean velocity in the vertical, the water depth and the nozzle diameter, as shown in Figure 2. The USD-49 is suitable for depth [integration of streams less than about 5 m in which the velocities do not exceed 2 m/s. The sampler is manufactured by Rickly Hydrological company.

Determination of the suspended sediment transport

The depth-averaged concentration can be determined as

[math]c\,=G\,/V\,[/math]

in which: [math]G[/math]= dry mass of sediment (mg), [math]V[/math]= volume of water sample (l).

The depth-integrated suspended sediment transport (in kg/m/s) can be determined as:

[math]S = \large\frac{Gh}{FT}[/math] or as [math]S = c\,u\,h\, = \large\frac{G}{V}\normalsize u\,h[/math]

in which: [math]G[/math]= dry mass of sediment (mg), [math]V[/math]= volume of sediment sample, including pores (m3),[math]h[/math]= depth of sampled zone (m), [math]u[/math]= depth-averaged velocity (m/s), [math]F[/math]= area of nozzle (m2), [math]T[/math]= sampling period (s).

The sampler cannot sample down to the stream bed surface. When the sampler touches the bed, the distance between the sample nozzle and the bed is about 0.1 m (see Figure 1). Thus, the depth of the sampled zone is about equal to the water depth minus 0.1 m. Another problem is the short sampling period at each specific point in the vertical. As a result concentration fluctuations are not averaged out and repeat samples are necessary.

See also

Summaries of the manual

Other internal links

External links

Further reading

INTER-AGENCY COMMITTEE on Water Resources (1963) Determination of Fluvial Sediment Discharge Report no. 14, St. Anthony Falls Hydr. Lab., Minneapolis, USA.

References

  1. Rijn, L. C. van (1986). Manual sediment transport measurements. Delft, The Netherlands: Delft Hydraulics Laboratory
The main author of this article is Rijn, Leo van
Please note that others may also have edited the contents of this article.

Citation: Rijn, Leo van (2020): USD-49 depth-integrating sampler. Available from http://www.coastalwiki.org/wiki/USD-49_depth-integrating_sampler [accessed on 31-10-2024]


The main author of this article is Roberti, Hans
Please note that others may also have edited the contents of this article.

Citation: Roberti, Hans (2020): USD-49 depth-integrating sampler. Available from http://www.coastalwiki.org/wiki/USD-49_depth-integrating_sampler [accessed on 31-10-2024]