Hydrodynamics of the Ballast-Free Ship Revisited

2010 ◽  
Vol 26 (04) ◽  
pp. 301-310
Author(s):  
Miltiadis Kotinis ◽  
Michael G. Parsons
Keyword(s):  
Fluid Dynamics ◽  
Experimental Studies ◽  
Power Reduction ◽  
University Of Michigan ◽  
Computational Hydrodynamics ◽  
Bulk Carrier ◽  
The Past ◽  
Computational Fluid Dynamics Cfd ◽  
The University ◽  
Propulsion Power

In order to clarify the existence and amount of a required propulsion power reduction possible with the efficient use of the Ballast-Free Ship concept on a Seaway-size bulk carrier, additional experimental and computational hydrodynamics studies were undertaken during the past year. Experimental studies performed in the University of Michigan Marine Hydrodynamics Laboratory (MHL) are described. Computational fluid dynamics (CFD) investigations performed using Star-CCMþ at both model and full scale are also presented.

Novae in the Magellanic Clouds

1979 ◽  
Vol 46 ◽  
pp. 96-101
Author(s):  
J.A. Graham
Keyword(s):  
Large Magellanic Cloud ◽  
Magellanic Cloud ◽  
Magellanic Clouds ◽  
University Of Michigan ◽  
The Past ◽  
Spectroscopic Information ◽  
Objective Prism ◽  
The University ◽  
Small Cloud ◽  
Low Dispersion

During the past several years, a systematic search for novae in the Magellanic Clouds has been carried out at Cerro Tololo Inter-American Observatory. The Curtis Schmidt telescope, on loan to CTIO from the University of Michigan is used to obtain plates every two weeks during the observing season. An objective prism is used on the telescope. This provides additional low-dispersion spectroscopic information when a nova is discovered. The plates cover an area of 5°x5°. One plate is sufficient to cover the Small Magellanic Cloud and four are taken of the Large Magellanic Cloud with an overlap so that the central bar is included on each plate. The methods used in the search have been described by Graham and Araya (1971). In the CTIO survey, 8 novae have been discovered in the Large Cloud but none in the Small Cloud. The survey was not carried out in 1974 or 1976. During 1974, one nova was discovered in the Small Cloud by MacConnell and Sanduleak (1974).

scholarly journals Development of mini-undulators for a table-top free-electron laser

2018 ◽  
Vol 36 (3) ◽  
pp. 396-404
Author(s):  
G. Petrov ◽  
J. Davis ◽  
W. Schumaker ◽  
M. Vargas ◽  
V. Chvykov ◽  
...  
Keyword(s):  
Free Electron ◽  
Permanent Magnets ◽  
Laser Machining ◽  
University Of Michigan ◽  
X Ray ◽  
The Past ◽  
Laser Wakefield ◽  
Electron Propagation ◽  
The University ◽  
Compact Sources

AbstractThe development of laser wakefield accelerators (LWFA) over the past several years has led to an interest in very compact sources of X-ray radiation – such as “table-top” free electron lasers. However, the use of conventional undulators using permanent magnets also implies system sizes which are large. In this work, we assess the possibilities for the use of novel mini-undulators in conjunction with a LWFA so that the dimensions of the undulator become comparable with the acceleration distances for LWFA experiments (i.e., centimeters). The use of a prototype undulator using laser machining of permanent magnets for this application is described and the emission characteristics and limitations of such a system are determined. Preliminary electron propagation and X-ray emission measurements are taken with a LWFA electron beam at the University of Michigan.

Ship Operational and Safety Aspects of Ballast Water Exchange at Sea

1994 ◽  
Vol 31 (04) ◽  
pp. 315-326
Author(s):  
John B. Woodward ◽  
Michael G. Parsons ◽  
Armin W. Troesch
Keyword(s):  
Bending Moment ◽  
Bending Moments ◽  
University Of Michigan ◽  
Bulk Carrier ◽  
Rough Water ◽  
Design Values ◽  
Wave Heights ◽  
Ballast Tanks ◽  
The University ◽  
Wave Induced

A dry bulk carrier, a tanker, and a containership—taken as typical of ships trading to U.S. ports—are analyzed for possible hazards caused by emptying and refilling ballast tanks at sea. Using hydrostatic data furnished by the shipowners, hull bending moments and stabilities are investigated to find the tank-emptying operations that produce the greatest changes in those parameters. As should be expected, bending moment changes do not exceed allowable stillwater values. Changes in GM are insignificant. The worst hydrostatic cases serve as a guide to conditions that should be analyzed in rough water. The University of Michigan SHIPMO program shows that in waves of 10-ft significant height wave-induced bending moments and shears are far below the design values published by the American Bureau of Shipping. On the other hand, in waves of 20-ft significant height, the maximum wave heights that occur occasionally can cause moments or shears that exceed design values. For the 20-ft case, both linear and nonlinear versions of SHIPMO are used.

Truss Spar Vortex Induced Motions: Benchmarking of CFD and Model Tests

2006 ◽  
Author(s):  
John Halkyard ◽  
Sampath Atluri ◽  
Senu Sirnivas
Keyword(s):  
Fluid Dynamics ◽  
Best Practices ◽  
Turbulence Modeling ◽  
Production Systems ◽  
Model Tests ◽  
The Past ◽  
Helical Strakes ◽  
Truss Spar ◽  
Computational Fluid Dynamics Cfd ◽  
Riser Design

Spar production systems are subject to Vortex Induced Motions (VIM) which may impact mooring and riser design. Helical strakes are employed to mitigate VIM. Model tests are typically required to validate the performance of the strakes. This paper will report on the results of benchmarking studies that have been conducted over the past few years to compare model tests with computational fluid dynamics (CFD). The paper discusses comparisons of CFD with model tests, “best practices” for the use of CFD for these classes of problems and issues related to turbulence modeling and meshing of problems at large Reynold’s numbers. This work is ongoing.

Open-Source Computational Fluid Dynamics in Engineering Education

2019 ◽  
Author(s):  
Ivaylo Nedyalkov
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Engineering Education ◽  
Open Source ◽  
Code Base ◽  
Undergraduate Engineering Education ◽  
Computational Fluid Dynamics Cfd ◽  
The University ◽  
University Of New Hampshire ◽  
Mathematics And Physics

Abstract Computational Fluid Dynamics (CFD) is widely used in industry but is not discussed sufficiently in undergraduate engineering education. In some cases, CFD is studied only from a mathematical perspective, focusing on computational partial differential equations, and in some cases it is introduced as a black-box tool. A hybrid CFD class was developed for undergraduate and graduate students at the University of New Hampshire, which combines the two approaches. The students are exposed to the mathematics and physics behind CFD, and they also utilize OpenFOAM — an open source CFD package — to work on practical problems. Since the code is open-source, the students are able to see and modify it. Although OpenFOAM is challenging due to the minimum graphical user interface, the code-base environment forces the students to learn what the code is doing. Sample assignments and project submissions from the students are presented in the paper.

scholarly journals DESIGN AND ANALYSIS OF AN AERODYNAMIC DOWNFORCE PACKAGE FOR A FORMULA STUDENT RACE CAR

2017 ◽  
Vol 18 (2) ◽  
pp. 212-224
Author(s):  
Muhammad Abid ◽  
Hafiz Abdul Wajid ◽  
Muhammad Zohair Iqbal ◽  
Shayan Najam ◽  
Ali Arshad ◽  
...  
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Wind Tunnel ◽  
Experimental Studies ◽  
Numerical Results ◽  
Experimental Results ◽  
Race Car ◽  
Rear Wing ◽  
Computational Fluid Dynamics Cfd ◽  
Front Wing

This paper presents design of aerodynamic downforce generating devices (front wing, rear wing and diffuser) to enhance the performance of the Formula Student Race Car using numerical and experimental studies. Numerical results using computational fluid dynamics (CFD) studies were primarily validated with the experimental results performed in the wind tunnel. It was concluded that the use of a downforce package can enhance the performance of the vehicle in the competition.

CFD Challenge: Modeling Blood Flow Dynamics in a Cerebral Aneurysm Using Fluent

2012 ◽  
Author(s):  
Nicholas Shaffer ◽  
Francis Loth
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Blood Flow ◽  
Cerebrospinal Fluid ◽  
Fluid Motion ◽  
Flow Dynamics ◽  
Cfd Modeling ◽  
Blood Flow Dynamics ◽  
Computational Fluid Dynamics Cfd ◽  
The University

The Biofluids Laboratory at the University of Akron has used Fluent [Ansys Inc., Canonsburg, PA] for image-based computational fluid dynamics (CFD) modeling of physiological flows since the lab’s inception in 2008. Recently our group has focused on modeling of pathophysiological problems in cerebrospinal fluid motion and air flow in the trachea, in addition to past work in cardiovascular problems.

scholarly journals Investigation of the Effect of Ski Jump on the Flow Dynamics around Generic Aircraft Carrier

2021 ◽  
Vol 71 (2) ◽  
pp. 296-303
Author(s):  
Rahul Thakur ◽  
K. Vignesh Kumar
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Degrees Of Freedom ◽  
Flow Dynamics ◽  
Aircraft Carrier ◽  
Six Degrees Of Freedom ◽  
The Past ◽  
Turbulent Airflow ◽  
Computational Fluid Dynamics Cfd ◽  
Flight Deck

The landing operation on an aircraft carrier is a complicated and risky process. Unlike land-based operations, the landing area available on carriers is in continuous motion in all the six degrees of freedom. The ski jump, flight deck, hull, and superstructure of the carrier interact with the oncoming wind’s flow-field which creates a turbulent airflow behind the carrier. This ‘burble effect’ is very dangerous and has caused various mishaps in the past. To complement the work being undertaken at IIT Delhi to study the flow dynamics in the carrier environment, the present study investigates the effect of ski jump and superstructure on the flow around the generic aircraft carrier (GAC). Computational fluid dynamics (CFD) studies are undertaken to simulate the airwake and establish a baseline with the ski jump. Subsequently, further studies are carried out to analyse the sensitivity of the wake to changes in carrier geometry. The introduction of the ski generates a major proportion of turbulence encountered in the aft by the approaching pilot. This is reduced significantly by optimising ski jump geometry in various ways.

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