Scientific and Technical Information Office 1980 SUMMARY Systematic investigations were performed on a variety of probes to determine their potential for possible application as sensors attached to helicopter blades to measure both the instantaneous angle of attack as well as the dynamic head during actual flight operations. After some preliminary considerations a sensor of essentially spherica...

Cl = section lift coefficient c = local chord length D = fading-memory constant G = nondimensional circulation l = section lift force/length m = number of points used in sine series expansion of circulation function N = consecutive iterations convergence parameter r = perpendicular distance from vortex tol = iteration relative tolerance of conversion U1 = freestream velocity magnitude w = downw...

In a previous paper, we addressed the problem of choosing constant values of altitude, speed, and angle of attack such that the orbital plane change during hypersonic flight is maximized for a fixed amount of propellant consumption. In the present paper, the restrictions of constant speed and angle of attack are removed. Necessary conditions for solutions to the resulting optimal control proble...

Computational fluid dynamics (CFD) is a powerful numerical tool that is becoming widely used to simulate many processes in the industry. In this work study of the stirred tank with 7 types of concave blade with CFD was presented. In the modeling of the impeller rotation, sliding mesh (SM) technique was used and RNG-k-ε model was selected for turbulence. Power consumption in various speeds in th...

The downstroke-to-upstroke transition of many insects is characterized by rapid wing rotation. The aerodynamic consequences of these rapid changes in angle of attack have been investigated using a mechanical model dynamically scaled to the Reynolds number appropriate for the flight of small insects such as Drosophila. Several kinematic parameters of the wing flip were examined, including the sp...

This paper presents two novel automated optimization approaches. The first one proposes a framework to optimize wind turbine blades by integrating multidisciplinary 3D parametric modeling, physics-based scheme, the Inverse Blade Element Momentum (IBEM) method, and Reynolds-averaged Navier–Stokes (RANS) simulation; second method introduces combining modeling an integrated goal-driven together wi...