Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 8 of 8 for “"ship airwake"”.
-
Contributions to Ship-Airwake-Rotor Coupling Characterization Using Controlled Forcing
<p>Shipboard helicopter operations occur within a highly unsteady environment referred to as the dynamic interface (DI), encompassing the coupled effects of the ship airwake, rotor wake, flight dynamics, and pilot response. A central aspect of the DI is the aerodynamic interaction between the ship …
-
Estimation and Mapping of Ship Air Wakes using RC Helicopters as a Sensing Platform
… of wireless in-situ measurement and mapping of ship airwake. The presented instrumentation system utilizes an RC helicopter as a carrier platform and uses the helicopter's dynamics for spatial 3D mapping of wind turbulence. The system was tested with a YP676 naval training craft to map ship …
-
Analysis of Ship Airwakes Using Modal Decomposition
<p>The three-dimensional, unsteady, and turbulent airwake produced by a scaled model of a generic Navy ship (Simple Frigate Shape No. 2) was investigated in a low-speed wind tunnel. Stereoscopic, time-resolved particle image velocimetry (TR-PIV) measurements were made at six different crosswise …
-
Dual Solver Computational Modeling of Ship-Helicopter Dynamic Interface Aeromechanics
Shipboard landings are a fundamental capability of naval aircraft operations and present a unique challenge to helicopter pilots due to the complex aerodynamic interactions between the ship airwake and the helicopter aerodynamics, known as the dynamic interface (DI). As such, detailed analysis and …
-
Constrained Control for Helicopter Shipboard Operations and Moored Ocean Current Turbine Flight Control
… control (MPC) framework for helicopter shipboard operations in high demanding sea-based conditions. A complex helicopter-ship dynamics interface has been developed as a system of implicit nonlinear ordinary differential equations to capture essential characteristics of the nonlinear …
-
Active and Passive Flow Control over the Flight Deck of Small Naval Vessels
… was collected at a set of grid points over the ship's flight deck using a single component hotwire. Results show that the use of porous surfaces decreases the unsteadiness of the flow field. Further improvements are found by injecting air through these porous surfaces, causing a reduction in …
-
Time-Resolved PIV Measurements of Ship Airwakes with Quartering Winds
<p>The unsteady, three-dimensional, turbulent airwake over the Simple Frigate Ship No. 2 (SFS2) with quartering wind flow directions was studied in a low-speed wind tunnel facility. Surface oil flow visualization and time-resolved stereoscopic and planar particle image velocimetry (PIV) …
-
A Study of Ship Airwakes Using Dual Plane Stereoscopic PIV
<p>The airwake of a model Simple Frigate Shape 2 (SFS2) was studied in a low-speed wind tunnel. This airwake was measured using a novel time-dependent, dual plane, stereoscopic particle image velocimetry approach. Two flow planes over the flight deck, one parallel and one perpendicular to the …