Calibration And Comparison Of An Improved Rotatable Single Hole Probe In 4, 6 And 8 Positions

Sitaram Nekkanti; Rambabu Dara

Abstract

An improved single hole probe with a measurement volume of 0.3 mm dia. is developed in the present investigation. The probe is calibrated in a low turbulence open jet tunnel at a velocity of 50 m/s in yaw and pitch angle range of + 40 deg. at an interval of 5 deg. A special probe holder is developed so that the probe can be positioned at intervals of 15 deg. The probe is calibrated in four positions at 90 deg. intervals, six positions at 60 deg. intervals with one pair of positions in vertical axis, six positions at 60 deg. interval with one pair of positions in horizontal axis and eight positions at 45 deg. interval. The calibration zone is divided into four zones, six zones and eight zones. In each of these zones the pressure from the corresponding probe is maximum and is treated as representative total pressure. Separate calibration coefficients for each zone are defined and calibration curves in different zones are presented. The calibration curves are found to vary monotonically and smoothly.

Abstract

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