In this study, the performance of a centrifugal pump is investigated by adding polyacrylamide (PAM) polymer over the working fluid which is tap water in this case. PAM is a long chain polymer that leads to reduce the wall shear stress and drag in a turbulent fluid. Three different blade profiles including radial, straight backward and circular backward have been examined. For this purpose, a ce...

Modeling of Unmanned Aerial Vehicles (UAV) propellers in a global, multidisciplinary aeroacoustic optimization was investigated. The modeling consists three aspects: geometry, aerodynamics, and aeroacoustics. Firstly, parametric geometry model established using chord, twist, sweep distributions along the radius, defined by splines to ensure smoothness. Additionally, airfoil parameters including...

Preview wind speed measurements from a forward looking Light Detection and Ranging (LIDAR) system located in the hub of a wind turbine can be used by a feedforward blade pitch control system to mitigate structural loads. For individual blade pitch control, a separate preview estimate of the effective wind speed encountered by each blade must be available. One way of providing an estimate of the...

Introductions to Philosophy There are many good introductions to philosophy: [21], [51] and [1] have the advantage of being short and cheap. There are a few books [42, 10, 33] that introduce philosophical ideas by analysing films which raise philosophical issues. One of the advantages of these books is that they allow you to say that you are doing valuable research for this module while watchin...

In above rated conditions, wind turbines are often subjected to undesirable high structural loading. We investigate two feedback control techniques in combination with a feedforward control method for reducing blade flap bending loads in above rated wind conditions. The feedback controls studied include both disturbance accommodating/tracking and integral augmented/repetitive types that incorpo...

A morphing segmented concept is proposed herein for future extreme-scale wind turbine systems. The morphing may be accomplished by using segmented blades connected by screw sockets and a tension cable system. At low wind and rotor speeds, the segmented blades are fully tensioned and set at high pitch to ensure start-up and maximum power at low speeds. At high rotor rpm, the cable tension can be...

A series of wind tunnel experiments was conducted to study the e ect of propeller solidity and thrust axis inclination on the propeller normalforce coe cient. Experiments were conducted in the Langley 14by 22-Foot Subsonic Tunnel with a sting-mounted, counterrotation, scalemodel propeller and nacelle. Con gurations had two rows of blades with combinations of 4 and 8 blades per hub. The solidity...

The horizontal axis wind turbine (HAWT) design with low speed requires blade geometry selection. analysis uses the potential flow panel method and integral boundary layer formulation to analyze around airfoil. element momentum (BEM) theory has an aerodynamic coefficient value along blade. Power calculates model shear pressure at each This research aims determine rotor based on performance, incl...

introduction: epulis fissuratum is often formed as a result of a poor fitting denture. the conventional treatment for this fibrous hyperplastic tissue is to excise it using a scalpel and to close the wound by a continuous or an interrupted suture. the increased utilization of lasers in dentistry also includes the utilization of carbon dioxide (co2) lasers in place of surgical scalpels in soft t...