We propose a four-quadrant propeller model suitable for energy-efficient motion planning of autonomous marine vehicles. The model can be used to capture the main features of experimental thrust and torque curves by using a small number of parameters. We explore the connection between the propeller thrust, torque, and efficiency curves and the lift and drag curves of the propeller blades. The mo...

This paper studies the flow around a propeller rotating in the reverse direction in a uniform free stream. Large eddy simulation is used to study this massively separated flow at a Reynolds number of 480 000 and advance ratios J = −0.5, −0.7 and −1.0. Simulations are performed on two grids; statistics of the loads and velocity field around the propeller show encouraging agreement between the tw...

Abstract The interaction between a propeller and its self-induced vortices originating on the ground is investigated in a scaled experiment. The velocity distribution in the flow field in two different planes containing the self-induced vortices is measured by particle image velocimetry (PIV). These planes are a wall-parallel plane in close proximity to the ground and a wall-normal plane just u...

OPENPROP, an open-source computational tool for the design and analysis of propellers and horizontal-axis turbines, is extended to provide estimates of normal stresses in the blades for both onand off-design operating conditions. The numerical model is based on propeller lifting theory, and the present implementation of the code includes an analysis capability to estimate the off-design perform...

The goal of this study is to analyze how the aeropropulsive benefits an over-the-wing distributed-propulsion (OTWDP) system at component level translate into benefit aircraft level, as well determine whether enhancement sufficient lead a reduction in overall energy consumption. For this, preliminary sizing partial-turboelectric regional passenger performed, and its performance metrics are compa...

OBJECTIVE With emergence and geographically expanding of antimalarial resistance worldwide, molecular markers are essential tool for surveillance of resistant Plasmodium parasites. Recently, single-nucleotide polymorphisms (SNPs) in the PF3D7_1343700 kelch propeller (K13-propeller) domain are shown to be associated with artemisinin (ART) resistance in vivo and in vitro. This study aims to inves...

While head motion is considered a significant problem in magnetic resonance imaging (MRI), there is no data to quantify its extent, severity, or effect on image quality. PROPELLER (Periodically Rotated Overlapping ParallEL Lines with Enhanced Reconstruction) MRI offers a novel means of quantifying and compensating for head motion. We performed axial T2-weighted PROPELLER (motion corrected: P-CR...

Propeller cavitation noise in the high frequency regime is broadband and yet audibly rhythmic. The study of these processes are important because the shaft and blade rates, as well as other identifying features of the ship, can in principle be inferred from propeller noise modulation characteristics. Conventional wisdom has been that propeller noise is an amplitude modulation of a wide sense st...

Abstract In this study, we adopt a coupled fluid-rigid body simulation using the moving computational domain method and multi-axis sliding mesh for takeoff, hovering, yawing flight of an electric vertical takeoff landing aircraft (eVTOL). The model has four pairs coaxial propellers, is divided into three domains to move eight propeller rotate propellers. As result, clarify behavior aerodynamic ...