Simulation regarding the forward part of underwater remotely operated vehicle designed for research in maritime and river districts

Over the last few decades, underwater mechanical system became a necessity for ocean research and exploration. The necessity of this type of equipment provides a new type of marine platforms in different areas of oceanographic research. Until this moment, the underwater vehicles have developed in different shapes, sizes and means of propulsion. Take into consideration these characteristics, we could determinate the type and mission of the vehicle. In this paper we investigate the problem regarding the pressure exerted of remotely operated vehicle. The remotely operated vehicle is designed in order to achieve different mission regarding the surveillance in lakes, harbors and maritime environment. This mission can take place through a remote control system placed onshore or on seaborne platforms. To improve the endurance of remotely operated vehicle, we performed a simulation study during which we compare the drag forces acts on the underwater vehicle according to its shape. Using SolidWorks program to create the body simulation vehicle and Ansys CFX to realise the simulation, this paper present the result simulated for the forward part of the vehicle.

Algorithm of developing rational geometric shape of the radio transparent nose radar fairing for the aircraft

The paper considers a complex criterion for assessing the characteristics of the radio-transparent fairing of the supersonic aircraft onboard radar. The algorithm for research performing which will allow to establish interrelation between radio, aerodynamic and the main geometrical characteristics of radio-transparent nose fairings, such as lengthening of the forward part of a fuselage, an angle of inclination of a tangent to a curve forming a body of rotation and a discriminant of a curve generator is developed. The process of forming the geometric shape of the onboard radar radio-transparent fairing of a supersonic aircraft is based on two interrelated processes: providing the appropriate radio technical characteristics of the fairing to meet the requirements for the range of the aircraft radar detection and minimizing the drag of the nose of the fuselage. Research following the proposed algorithm allows forming technical recommendations for the selecting rational geometric parameters of onboard radar radio-transparent fairing of a supersonic aircraft at the early stages of aircraft design.

Polarimetry for a storage-ring electric-dipole-moment measurement

These proceedings summarize the progress which has been made within the Jülich Electric Dipole Moment Investigations (JEDI) Collaboration on deuteron beam polarimetry for a storage-ring electric-dipole-moment (EDM) measurement. The design of a dedicated EDM polarimeter requires a precise database for optimization purposes. To address this need, a measurement of a deuteron-carbon scattering database has been performed with the forward part of the WASA-at-COSY detector. Preliminary results for vector analyzing powers and unpolarized differential cross sections for different deuteron beam energies are presented.

Proposal and Experimental Verification of Design Guidelines for Centrifugal Compressor Impellers With Curvilinear Element Blades to Improve Compressor Performance

This study numerically and experimentally examines the effects of applying curvilinear element blades to fully shrouded centrifugal impellers on the performance of the centrifugal compressor stages. The curvilinear element blades we developed for centrifugal turbomachinery were defined by the coordinate transformations between a revolutionary flow-coordinate system and a cylindrical coordinate system. All the blade sections in the transferred cylindrical coordinate system were moved and stacked spanwise in accordance with the given “lean profile,” which meant the spanwise distribution profile of movement of the blade sections, to form a new leaned blade surface. The effects of the curvilinear element blades on the impeller flowfield were investigated using numerical simulations, and the optimum design guidelines for impellers with curvilinear element blades were considered. Then, a new impeller using these design guidelines was designed and the performance improvement of a new compressor stage was evaluated by numerical simulations. As mentioned in several papers, we numerically confirmed that curvilinear element blades with a negative tangential lean (TGL) profile improved the velocity distribution and stage efficiency because they help to suppress the secondary flows in the impeller. The negative TGL mentioned in this paper represents the lean profile in which the blade hub end leans forward in the direction of the impeller rotation compared to the blade shroud end. At the same time, we also found that the stall margin of these impellers deteriorated due to the increase in relative velocity deceleration near the suction surface of the shroud in the forward part of the impeller. Therefore, we propose new design guidelines for impellers with the curvilinear element blades by applying a negative TGL to line element blades in which the blade loading of the shroud side in the forward part of the impeller is reduced. We confirmed from the numerical simulation results that the performance of the new compressor stage improved compared to that in the corresponding conventional one. The new design guidelines for the curvilinear element blades were experimentally verified by comparing the performance of the new compressor stage with the corresponding conventional one. The measured efficiency of the new compressor stage was 2.4% higher than that of the conventional stage with the stall margin kept comparable. A comparison of the measured velocity distributions at the impeller exit showed that the velocity distribution of the new impeller was much more uniform than that of the conventional one.