Pitching moment

About: Pitching moment is a research topic. Over the lifetime, 3213 publications have been published within this topic receiving 38721 citations.

A novel strategy for designing and manufacturing a fixed wing mav for the purpose of increasing maneuverability and stability in longitudinal axis

Abstract: In this study, a novel simple strategy is proposed to choose and accommodate an airfoil based on the effects of airfoil type and plan-form shape on the flight performance of a micro air vehicle. In this strategy, after defining flight mission, the weight of the micro air vehicle is estimated and then, aerodynamic parameters and thrust force are calculated. In the next step, some different plan-forms and airfoils are investigated to be selected for decreasing the stall region in high attack anglesby open source software named XFLR5. Having calculated the aerodynamic center, the pitching moment needed to stabilize the micro air vehicle is computed. Due to the static margin, the airfoil camber line is changed to stabilize the micro air vehicle and then, its thickness is improved to reach to a high aerodynamic characteristic. To evaluate the software results, some flight tests are performed which then compared to the software results that show a good agreement. Finally, some adjustments and improvements are made on the micro air vehicle and then, its performance is obtained by the flight tests. The flight test results show it has an excellent aerodynamic performance, stability and maneuverability.

Subsonic and Transonic Low-Reynolds-Number Airfoils with Reduced Pitching Moments

Abstract: A subsonic and a transonic airfoil are presented for application in a high-altitude long-endurance aircraft and a very-high-altitude aircraft, respectively. The subsonic airfoil is designed for a lift coefficient c(l) = 1.4 at a chord Reynolds number Re = 700,000 and a very low Mach number. The transonic airfoil is designed for c(l) = 1.0 at Re = 500,000 and a transonic Mach number M = 0.7. Both airfoils are developed to perform as well or better than previously designed airfoils. However, the present airfoils are developed for a constrained pitching moment to reduce aircraft trim drag and to relieve, to some extent, the torsional loads in the typically high-aspect-ratio wings. The beneficial effects of a cruise flap and of boundary-layer transition control on the off-design performance characteristics are illustrated.

Numerical Prediction of Pitch Damping Derivatives for a Finned Projectile at Angles of Attack

Abstract: This study extends the time-accurate forced-oscillation planar pitching ReynoldsAveraged method to predict the pitch damping dynamic stability derivative at non-zero angles of attack for projectile munitions. The simulations were performed for two configurations of the Army-Navy Finner Missile at Mach 1.96, for two Reynolds number test conditions, and for angles of attack ranging from 0–85°. Comparisons with archival wind tunnel data indicated good to excellent numerical prediction for the pitch damping moment. For the static aerodynamic coefficients, the method predicts the pitching moment with excellent accuracy, and the pitching moment slope with fair accuracy.