Introduction Diffusion-weighted MRI (DWI) provides a non-invasive method for in vivo evaluation of tissue water mobility. Most DWI studies employ single-shot DWEPI techniques which can suffer severe artifacts and image distortion in abdominal imaging applications. Multi-shot TSE-based DW-PROPELLER [1] may overcome these limitations. DW-PROPELLER for brain [2] and abdominal [3] imaging has demon...

Today’s unmanned aerial vehicles are being utilized by numerous groups around the world for various missions. Most of the smaller vehicles that have been developed use commercially-off-the-shelf parts, and little information about the performance characteristics of the propulsion systems is available in the archival literature. In light of this, the aim of the present research was to determine ...

The objective of the drive shaft is to connect with the transmission shaft with the help of universal joint whose axis intersects and the rotation of one shaft about its own axis results in rotation of other shaft about its axis. Shafts must be exceptionally tough and light to improve the overall performance of the vehicle. Automobile industries are exploring composite materials in order to obt...

This paper proposes a thrust estimation scheme for marine propellers in four-quadrant operations. To calculate the thrust and torque coefficients of screw propeller in four-quadrant, a Chebyshev fit expression of the propeller properties in four-quadrant for surface vessel is given, and then it is changed into an ordinary polynomial expression. These expressions are suitable for calculating the...

this paper describes a contra-rotating propeller (crp) system to calculate the hydrodynamic characteristics and then design the optimum operational condition to be installed on two different large bulk carriers and vlcc. the method is based on boundary element method (bem) to obtain the hydrodynamic performance of any complicated configuration such as crp system, and then the optimum propeller ...

This paper investigates the influence of the propeller on the drag of twin self-propelled AUVs, firstly, to examine the fleet performance for various propulsive conditions of leading and following AUV and, secondly, to study the parametric influence of transverse separations and longitudinal offsets on the fleet’s drag. A series of CFD RANS-SST simulations have been performed at the Reynolds Nu...

This study presents the results of cavitation tunnel tests carried out with model propeller of a Fisheries Research Vessel (FRV) and those of noise measurements with its full-scale propeller to validate the low-noise performance of this propeller. The tests involve the simulation of a target wake using a wake screen and the determination of the nature and extent of the observed cavitation behin...

Contra-rotating propellers have renewed interest from the naval architecture community, because of the recent development of electric propulsion drives and podded propulsors. Contrarotating propulsion systems have the hydrodynamic advantages of recovering part of the slipstream rotational energy which would otherwise be lost utilizing a conventional screw propeller system. The application of th...