Peak flow measurement device
A peak flow measurement device comprises a hollow body ( 1 ) having an inlet ( 8 ) for receiving fluid and an outlet ( 3 ), wherein the inlet ( 8 ) and outlet ( 3 ) are spaced apart from each other, the cross-sectional area of the body being greater than the cross-sectional area of the outlet and wherein in use the device is oriented such that the inlet is above the outlet and the measured peak flow is proportional to the maximum height ( 11 ) of fluid within the body.
1. A fluid flow measurement device comprising:
a hollow body having an inlet for receiving fluid and an outlet that defines a flow rate of fluid therethrough, wherein:
the inlet and outlet are spaced apart from each other,
the cross-sectional area of the body is greater than the cross-sectional area of the outlet,
in use, the device is oriented such that the inlet is above the outlet and the measured fluid flow is proportional to the height of fluid within the body,
the hollow body comprises at least two portions having different cross sectional areas, and
the cross sectional area of the hollow body increases step-wise at a height on the body that relates to a predetermined flow rate of fluid through the outlet.
2. A device as claimed in claim 1 , wherein the outlet is circular in cross-section.
3. A device as claimed in claim 1 , wherein the outlet is so shaped and dimensioned as to present a hydro-dynamically thin orifice to fluid efflux.
4. A device as claimed in claim 1 , further comprising scale means for determining the peak height of fluid in the hollow body.
5. A device as claimed in claim 4 , wherein the scale means comprises at least one indicia.
6. A device as claimed in claim 4 , wherein the scale means comprises at least two different coloured bars each representing a different peak flow rate or range of peak flow rates.
7. A device as claimed in claim 4 , wherein the scale means comprises heat sensitive material providing a semi-permanent or permanent indication of fluid height.
8. A device as claimed in claim 7 , wherein the heat sensitive material is applied to a wall of the hollow body.
9. A device as claimed in claim 8 , wherein the heat sensitive material is applied to a portion of the wall of the hollow body with reduced wall thickness.
10. A device as claimed in claim 1 , wherein the hollow body is constructed from a transparent material.
11. A device as claimed in claim 1 , wherein the inlet is connectable to a funnel.
12. A device as claimed in claim 1 , wherein the hollow body is cylindrical in shape.
13. A device as claimed in claim 12 , wherein the hollow body has a diameter of 30 mm and the outlet orifice has a diameter of 4 mm.
14. A device as claimed in claim 1 , wherein scale means for determining the peak height of fluid passing through the hollow body comprises the step-wise changes in the cross-sectional area of the hollow body.
15. A device as claimed in claim 1 , wherein each step-wise increase in the cross-sectional area of the hollow body includes a step, and wherein at least one pyramidal tooth is incorporated into the rim of each step.
16. A device as claimed in claim 1 , wherein the fluid is urine.
17. A device as claimed in claim 1 further comprising a receptacle for catching effluxed fluid.
18. A device as claimed in claim 1 , wherein each step-wise increase in the cross-sectional area of the hollow body includes a step, and wherein each step extends perpendicularly relative to a wall of the hollow body.
19. A device as claimed in claim 1 , wherein each step-wise increase in the cross-sectional area of the hollow body includes a step, and wherein a plurality of pyramidal teeth is incorporated into the rim of each step.
20. A method for determining the peak flow rate of a fluid using the device as claimed in claim 1 , comprising the steps of
(a) introducing fluid to the inlet of the device; and
(b) determining the peak fluid level within the hollow body;
wherein the peak fluid flow rate is proportional to the maximum height of fluid in the body.