Static pressure probe and method
AssigneeThe Garrett Corporation
InventorsWalter L. Clark, Trevor G. Sutton
Life of this patent
Estimating the term…
Abstract
A static pressure probe capable of measuring the static pressure of an airstream in which particle contamination and/or ice formation at the airflow receiving orifice of the probe is minimized by method and apparatus presenting a stagnant air pocket directly adjacent and downstream of the orifice.
Claims18
A probe for use in measuring static pressure of an airstream comprising:
- a flow pickup tube having an open end disposed in a downstream direction relative to said airstream, said open end presenting an orifice of preselected size;
- and
- a protective hood carried with said tube in surrounding relationship to said open end of the tube, said hood being substantially larger than said tube and having an open distal end disposed downstream of said orifice and presenting an opening communicating with said airstream, said opening being at least twice as large as said orifice.
In a gas turbine engine having a compressor delivering a pressurized airstream to a plenum chamber for subsequent delivery to a combustion chamber and then exhaust across a turbine to drive said turbine, a probe for measuring static pressure in said plenum chamber, comprising:
- a flow pick up tube having an orifice disposed in said plenum chamber facing in a downstream direction relative to the airstream therein;
- and
- a protective hood carried with said tube surrounding said orifice and having an open distal end disposed downstream of said orifice, said open distal end being substantially larger than said orifice and having a relatively large unrestricted opening communicating with said airstream, said opening of the distal end being substantially larger than said orifice.
A static probe for measuring static pressure of an airstream comprising:
- a pickup tube having an open distal end presenting a substantially circular opening facing in a direction at least approximately ninety degrees to the direction of said airstream, said opening being sufficiently large to prevent plugging thereof by ice formation;
- and
- means recessed in said tube upstream of said open distal end for defining an orifice for receiving airflow from said airstream, said orifice having a diameter less than one-half the diameter of said opening.
A probe for sensing static pressure of an airstream comprising:
- a hollow tubular member of generally L-shaped configuration having a smaller leg disposed generally parallel to said airstream, said smaller leg having a circular orifice at an end thereof facing downstream relative to said airstream, said orifice transmitting airflow from said airstream to said hollowed tubular member, said member having a longer leg extending generally transversely to said airstream;
- means communicating with said longer leg of said tubular member for measuring the pressure of airflow received therein;
- and
- said smaller leg including a cup-shaped, cylindrical hood secured to said longer leg and having a transverse end wall at an upstream end having an aperture therein defining said orifice, said hood further including a closed cylindrical wall extending downstream from said transverse end wall to terminate at a downstream end disposed downstream of said circular orifice, said cylindrical wall having a diameter substantially greater than said orifice and disposed in concentric surrounding relationship thereto, said downstream end of said cylindrical wall being open to present a circular opening facing downstream and communicating with said airstream whereby airflow from said airstream enters said opening and passes upstream within the interior of said hood prior to entering said orifice, said hood operable to minimize ingestion of particles capable of plugging said orifice, said opening being substantially larger than said orifice to prevent plugging of said opening by ice formation and to minimize formation of ice at said orifice.
Dependencies are inferred from the claim text.