Kiel probe

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A Kiel probe from the Rockwell-MBB X-31 experimental aircraft X-31 Kiel Probe Close-up Showing Inside.jpg
A Kiel probe from the Rockwell-MBB X-31 experimental aircraft

A Kiel probe is a device for measuring stagnation pressure or stagnation temperature in fluid dynamics. It is a variation of a Pitot probe where the inlet is protected by a "shroud" or "shield." Compared to the Pitot probe, it is less sensitive to changes in yaw angle, and is therefore useful when the probe's alignment with the flow direction is variable or imprecise. [1]

In fluid dynamics, stagnation pressure is the static pressure at a stagnation point in a fluid flow. At a stagnation point the fluid velocity is zero and all kinetic energy has been converted into pressure energy (isentropically). In an incompressible flow, stagnation pressure is equal to the sum of the free-stream dynamic pressure and free-stream static pressure.

In thermodynamics and fluid mechanics, stagnation temperature is the temperature at a stagnation point in a fluid flow. At a stagnation point the speed of the fluid is zero and all of the kinetic energy has been converted to internal energy and is added to the local static enthalpy. In incompressible fluid flow, and in compressible flow, the stagnation temperature is equal to the total temperature at all points on the streamline leading to the stagnation point. See gas dynamics.

Fluid dynamics Sub-discipline of fluid mechanics

In physics and engineering, fluid dynamics is a subdiscipline of fluid mechanics that describes the flow of fluids—liquids and gases. It has several subdisciplines, including aerodynamics and hydrodynamics. Fluid dynamics has a wide range of applications, including calculating forces and moments on aircraft, determining the mass flow rate of petroleum through pipelines, predicting weather patterns, understanding nebulae in interstellar space and modelling fission weapon detonation.

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References

  1. Kiel, G. Total Head Meter with Small Sensitivity to Yaw, Technical Memorandum 775 (PDF). Washington, DC: National Advisory Committee for Aeronautics. p. 10. Retrieved 10 December 2014.