AN INVESTIGATION OF AN APPROACH TO THE PROBLEM OF DETERMINING THE OPTIMUM DESIGN OF SHROUDED PROPELLERS. APPENDIX I. VORTEX SYSTEM. APPENDIX II. CALCULATION OF THRUST AND POWER. APPENDIX III. DETERMINATION OF THE OPTIMUM LOADING FOR A HEAVILY LOADED PROPELLER HAVING AN INFINITE NUMBER OF BLADES. APPENDIX IV. OUTLINE OF DESIGN PROCEDURES FOR SHROUDED PROPELLERS

1960 ◽  
Author(s):  
JR. CASTLES ◽  
GRAY WALTER ◽  
ROBIN B.
Keyword(s):  
Optimum Design ◽  
Infinite Number ◽  
Vortex System ◽  
Design Procedures

Determination of Stresses in Cemented Lap Joints

1953 ◽  
Vol 20 (3) ◽  
pp. 355-364
Author(s):  
R. W. Cornell
Keyword(s):  
Differential Equations ◽  
Infinite Number ◽  
Lap Joints ◽  
The Other ◽  
Complete Analysis ◽  
Stress Distributions ◽  
Lap Joint ◽  
Analogy Method ◽  
Set Up

Abstract A variation and extension of Goland and Reissner’s (1) method of approach is presented for determining the stresses in cemented lap joints by assuming that the two lap-joint plates act like simple beams and the more elastic cement layer is an infinite number of shear and tension springs. Differential equations are set up which describe the transfer of the load in one beam through the springs to the other beam. From the solution of these differential equations a fairly complete analysis of the stresses in the lap joint is obtained. The spring-beam analogy method is applied to a particular type of lap joint, and an analysis of the stresses at the discontinuity, stress distributions, and the effects of variables on these stresses are presented. In order to check the analytical results, they are compared to photoelastic and brittle lacquer experimental results. The spring-beam analogy solution was found to give a fairly accurate presentation of the stresses in the lap joint investigated and should be useful in analyzing other cemented lap-joint structures.

Optimum Design of Elastically Supported Gyroscopes for Ship Stabilization

1984 ◽  
Vol 106 (4) ◽  
pp. 387-392
Author(s):  
K.-N. Lee ◽  
A. Seireg
Keyword(s):  
Optimal Design ◽  
Dynamic Model ◽  
Optimum Design ◽  
Design Procedures ◽  
System Parameters ◽  
Ship Roll ◽  
Elastically Supported ◽  
Elastic Spring

The study reported in this paper deals with the development of a dynamic model for the analysis of elastically supported gyroscopic absorber systems for ship stabilization. The gryoscopes are mounted on elastically supported platforms at the fore and aft ends of the ship to minimize both the roll and pitch movements. Springs and dampers are also utilized between the gyroscope gimbal and the platform. Several design configurations of the absorber are considered. Optimal design procedures are utilized to find the system parameters for best performance in each case. The performance of the resulting optimum absorber shows that introducing the elastic spring and damper between the gimbal and platform has a significant effect on reducing the ship-roll action.

scholarly journals Problems of Menotactic Orientation According to the Polarized Light of the Sky

1975 ◽  
Vol 30 (1-2) ◽  
pp. 88-90 ◽  
Author(s):  
Kuno Kirschfeld ◽  
M. Lindauer ◽  
H. Martin
Keyword(s):  
Infinite Number ◽  
Polarized Light ◽  
The Sun ◽  
Number Of Solutions ◽  
Special Cases ◽  
Linearly Polarized ◽  
Vector Direction

Abstract It is shown that the knowledge of the E-vector direction of the linearly polarized light at any point of the sky alone is insufficient for the determination of the position of the sun. If the E-vector direction of a second point is not known the knowledge of at least one other parameter is necessary. This parameter might be the height of the sun over the horizon. With the knowledge of the height the infinite number of solutions for the sun’s position becomes reduced to two, or in special cases to one. These cases are derived.

Characteristics of a Self-Lubricated Stepped Thrust Pad of Infinite Width With Compressible Lubricant

1959 ◽  
Vol 81 (2) ◽  
pp. 135-145 ◽  
Author(s):  
Kikuo C. Kochi
Keyword(s):  
Optimum Design ◽  
Practical Interest ◽  
Numerical Data ◽  
Numerical Results ◽  
Design Parameters ◽  
Analytic Expressions ◽  
Thrust Pad ◽  
Compressible Lubricant

Harrison’s equation for the pressure in a gas-lubricated bearing of infinite width is solved for a thrust pad with stepped configuration. Analytic expressions for the pressure and load are developed. Numerical results are presented graphically. The analytic expressions together with the numerical data permit most of those characteristics of the stepped pad of practical interest to be completely determinable. Determination of optimum design parameters is given by a pair of graphs.

The Optimum Design of Compression Surfaces having Unflanged Integral Stiffeners

1954 ◽  
Vol 58 (527) ◽  
pp. 765-768 ◽  
Author(s):  
E. J. Catchpole
Keyword(s):  
Optimum Design ◽  
Rapid Determination ◽  
Cross Sectional

SummaryA method is developed enabling rapid determination of the optimum cross-sectional dimensions of compression surfaces having unflanged integral stiffeners, and consideration is given to the effects of practical limitations on the design. The theoretical efficiency of the optimum integral design is found to be only 85 per cent, of that of optimum Z-stringer design.

scholarly journals The determination of fatigue limits under alternating stress conditions

1914 ◽  
Vol 90 (620) ◽  
pp. 411-425 ◽  
Keyword(s):  
Infinite Number ◽  
Fatigue Tests ◽  
Test Results ◽  
Railway Company ◽  
Standard Of Comparison ◽  
The Subject ◽  
Pull Tests ◽  
Push And Pull ◽  
The Relationship

In the year 1867 A. Wöhler, locomotive superintendent of a railway company in Berlin, exhibited at the Paris Exhibition the results of some experiments on the endurance of metals, and was thereupon engaged by the Prussian Government to carry out the more exhaustive enquiry into this subject with which his name is always associated. The results of his labours were published in 1871, and were highly appreciated, but few additional experiments were made until the subject was again taken up successively by Sir Benjamin Baker, Reynolds and Smith, Rogers, Stanton and bairstow, Eden, Rose and Cunningham, and Prof. Hopkinson. All these experiments are confined either to fatigue bending or to push and pull tests, using only steel or iron, whereas the present ones include a large number of torsion fatigue tests on various metals. Until comparatively recently there was no satisfactory standard of comparison for fatigue tests, the determination of the asymptote or limiting fatigue stress for an infinite number of revolutions from a few irregular test results leading to very uncertain conclusions, so much so that by some it was considered very doubtful whether there were any real fatigue limits, while others adopted as standards of comparison the fatigue stresses which would cause fractures at the millionth repetition. The first problem which had to be investigated was therefore to ascertain the relationship between the intensities of fatigue stresses and the numbers of repetitions of these stresses which would cause fracture; and, should this relationship be found to indicate the existence of a limiting stress for an infinite number of revolutions, or more briefly of a fatigue limit, then the next step would have to be its exact determination.

Estimation Local Strength of Bow Structure for High Tensile Steel Yacht Based on Optimum Design

2006 ◽  
Vol 326-328 ◽  
pp. 1463-1466
Author(s):  
Joo Shin Park ◽  
Yun Young Kim ◽  
Tetsuya Yao
Keyword(s):  
Optimum Design ◽  
Minimum Weight ◽  
Analysis Model ◽  
Element Analysis ◽  
Stress Criterion ◽  
Local Strength ◽  
The Finite Element Analysis ◽  
Small Craft ◽  
Weight Design

The optimum design for bow structure of high tensile steel yacht belongs to the nonlinear constrained optimization problem. The determination of scantlings for the bow structure is a very important matter out of whole structural design process of a yacht. The optimum design results are produced with the use of Real-coded Micro-Genetic Algorithm including evaluation LR small craft guideline, so that they can satisfy the allowable stress criterion. In this study, the minimum weight design of bow structure on the HTS yacht was carried out based on the finite element analysis. An analysis model is a bow structure of HTS yacht with structural scantling derived from the minimum weight optimization. The weight of bow structure and the main dimensions of structural members are chosen as an objective function and design variable, respectively. Optimization results were compared with a pre-existing design. From the FE analysis results, bow structure with high tensile steel (AH40) designed by using RμGA has a volume efficiency of 19% than the design of the actual mild yacht.

Sign in / Sign up

Export Citation Format

Share Document