Pressure Differential Angle of Attack Measuring System: THEORATICAL INVESTIGATION OF PRESSURE DIFFERENTIAL ANGLE OF ATTACK MEASURING SYSTEM FOR FLUSH PORT AIR DATA SYSTEM

The purpose of this research activity is towards identifying the location to install Flush Port Air Data System (FADS) on different aerodynamic shapes. FADS systems typically have in excess of 10 pressure ports/sensors. Flush Port Pressure Sensors are symmetrically placed on the airframe. The pressure measured at each port varies as the airframe manoeuvres. Pressure Difference between corresponding ports on top and bottom of an aerodynamic body correspond to changes in AoA. Potential Flow Theory can be used for preliminary analysis because of its linearity for predicting the flow behaviour on various simpler aerodynamic shapes e.g. cylinder, sphere, wedge, cone and airfoil. The flow patterns obtained from this theory are simulated in MatLab to calculate Pressure Differential variation with respect to AoA on them. Also the variations on these surfaces are then compared with one another to check whether the front part of these surfaces correspond to the same Pressure Differential or not. On the basis of this Pressure Differential Variation w.r.t AoA, the location to install the Pressure Differntial AOA measuring instrument is suggested.