Sampling device for withdrawing a representative sample from single and multi-phase flows

• US 4,442,720 A
• Filed: 01/06/1983
• Issued: 04/17/1984
• Est. Priority Date: 07/29/1980
• Status: Expired due to Fees

• Current Assignee: United States Department of Energy (Government of the United States of America)
• Original Assignee: United States Department of Energy (Government of the United States of America)
• Inventors: Cliff, William C., Apley, Walter J., Creer, James M.
• Primary Examiner(s): Swisher, S. Clement
• Application Number:
  US06/456,146
• Time in Patent Office: 467 Days
• Field of Search: 73/863.51, 73/863.54, 73/863.31, 73/863.58, 73/861.66
• US Class Current: 73/863.31
• CPC Class Codes: G01N 1/16 with provision for intake at several levels G01N1/2035 G01N1/12, G01N1/14 take precedence
• CPC Class Codes: G01N 1/2035 by deviating part of a fluid stream, e.g. by drawing-off or tapping
• CPC Class Codes: G01N 2001/1037 from an enclosure (hazardous waste, radioactive)
• CPC Class Codes: G01N 2001/2092 Cross-cut sampling
• CPC Class Codes: G01N 2001/225 isokinetic, same flow rate for sample and bulk gas

Abstract

A fluid stream sampling device has been developed for the purpose of obtaining a representative sample from a single or multi-phase fluid flow. This objective is carried out by means of a probe which may be inserted into the fluid stream. Individual samples are withdrawn from the fluid flow by sampling ports with particular spacings, and the sampling parts are coupled to various analytical systems for characterization of the physical, thermal, and chemical properties of the fluid flow as a whole and also individually.

Claims

1. A probe device for simultaneously obtaining a plurality of representative samples from a multi-phase fluid stream flowing through a well pipe, said fluid stream having a plurality of zones of pre-determined cross-sectional area to be simultaneously sampled, comprising:

a right cylindrical probe,

drive rod means coupled to said probe which may be positioned within said fluid stream by said drive rod means, the maximum extension of said probe limited by said well pipe containing said fluid stream, said probe capable of being removed completely from said fluid stream,

a plurality of sampling lines, each sampling line terminating in a port at the surface of said probe, said sampling ports in said probe lying along a diameter of said well pipe, each port being positioned in the probe so as to withdraw a sample from a pre-determined zone of said fluid stream, the area of each port proportional to the cross-sectional area of the zone of the fluid stream it samples,

means for measuring the differences in static pressure among said sampling ports, said means including a plurality of static pressure tap lines branching off the sampling lines respectively, and further including a plurality of differential pressure transducers in fluid communication with said plurality of static pressure tap lines respectively, and

3. The device of claim 1, wherein said sampling ports extend solely along a radius of said well pipe.

4. The device of claim 1, wherein said probe cross section parallel to said fluid stream is tear-drop shaped with the largest end facing into flow direction (22) of said fluid stream.

5. The device of claim 1, wherein said sampling ports have straight sides of entry into said sampling port lines.

6. The device of claim 1, wherein said sampling ports have convex sides of entry into said sampling port lines.

7. The device of claim 1, wherein said sampling ports have concave sides of entry into said sampling port lines.

8. The device of claim 1, wherein an individual analysis means is coupled to fluid samples from said sampling port lines for individual analysis, thereby providing a positional map of the characteristic properties of said fluid stream.

9. The device of claim 1 wherein said plurality of throttle means regulate the pressure in the plurality of sampling lines respectively such that the differences in pressure among said static pressure tap lines is the null value, whereby the sampling lines simultaneously withdraw a plurality of isokinetic samples from the fluid stream.

10. The device of claim 1 wherein said throttle means regulate the pressure in the sampling lines to enhance or retard sample withdrawal at selected sampling ports.

11. The device of claim 1 wherein each port is of equal area and spaced at variable distances along the probe.

12. The device of claim 1 wherein each port is of variable area and spaced at equal distances along the probe.

13. The probe device of claim 1 wherein said well pipe is provided with a recess on its inner wall, and said right cylindrical probe has a hemispherical end which may be seated in said recess of said well pipe, such that said recess limits the maximum extension of said probe into said well pipe.

2. a plurality of throttle means for regulating the pressure in each sampling line respectively responsive to the pressure in each static pressure tap line respectively until the differences in pressure among said static pressure tap lines are a predetermined value, whereby the sampling lines simultaneously withdraw a plurality of representative samples from said fluid stream.