An Optimum Design Methodology for Planar-Type Coaxial Probes Applicable to Broad Temperature Permittivity Measurements

2008 ◽  
Vol 56 (3) ◽  
pp. 684-692 ◽  
Author(s):  
Namgon Kim ◽  
Jeonghoon Yoon ◽  
Sungjoon Cho ◽  
Jeiwon Cho ◽  
Changyul Cheon ◽  
...  
Keyword(s):  
Optimum Design ◽  
Design Methodology ◽  
Coaxial Probes ◽  
Permittivity Measurements

Optimization and Standardization of Flanged and Flued Expansion Joint Design

2019 ◽  
Vol 141 (3) ◽  
Author(s):  
Kamlesh M. Chikhaliya ◽  
Bhaveshkumar P. Patel
Keyword(s):  
Heat Exchanger ◽  
Optimum Design ◽  
Design Methodology ◽  
Thick Wall ◽  
Process Conditions ◽  
Expansion Joint ◽  
Standard Requirement ◽  
Spring Rate ◽  
Tube Heat Exchanger ◽  
Heat Exchanger Design

Flanged and flued type expansion joint (thick wall expansion bellow) used as an integral part of many shell and tube heat exchanger where process conditions produce differential expansion between shell and tubes. It provides flexibility for thermal expansion and also functions as a pressure retaining part. Design of expansion joints is usually based on trial and error method in which initial geometry must be assumed, and accordingly maximum stresses and spring rate are be calculated. Inadequate selection of geometry leads to higher tubesheet and bellow thickness, which increases cost of equipment. This paper presents standardization and optimum design approach of flange and flued expansion bellow fulfilling ASME VIII-1 and TEMA standard requirement. Methodology to define expansion bellow geometry is developed, and geometry dimensions are tabulated for expansion bellow diameter from 300 to 2000 mm and thickness from 6 to 30 mm. Each defined geometry is analyzed using finite element method, and maximum von Mises stresses are calculated for bellow axial displacement from 0.5 to 1.5 mm and internal pressure from 0.1 to 6.5 MPa. Spring rate is also calculated for each defined geometry for consideration in tubesheet calculation. Accordingly, optimum design methodology is developed, tested, and compared with existing design. Results depicted that proposed standardization approach and design methodology will optimize expansion bellow and tubesheet thickness and will also save considerable time in finalization of heat exchanger design.

scholarly journals RELIABILITY BASED DESIGN OF RUBBLE-MOUND BREAKWATER

1988 ◽  
Vol 1 (21) ◽  
pp. 153
Author(s):  
Masato Yamamoto ◽  
Kazumasa Mizumura ◽  
Taiji Endo ◽  
Naofumi Shiraishi
Keyword(s):  
Water Level ◽  
Optimum Design ◽  
Failure Probability ◽  
Design Methodology ◽  
Construction Cost ◽  
Probabilistic Design ◽  
Reliability Based Design ◽  
Rubble Mound ◽  
Reduced Risk

The object of this present research is to study probabilistic design of armor blocks protecting composite breakwaters and to produce optimum design methodology for S-shaped breakwaters in terms of failure probability and construction cost. Failure probability in the vicinity of the still water level is greatest in the case of uniform sloped breakwaters. Therefore,S-shaped breakwaters of which the slope near the still water level is milder have a reduced risk of damage compared to uniform sloped ones. The optimum design index presents good economics and reliability in rubble-mound breakwater design.

Damped Vibration Absorbers Applied to Lateral Modes of Rotating Machinery

1999 ◽  
Author(s):  
Lyn M. Greenhill ◽  
Linda F. Raven
Keyword(s):  
Detailed Analysis ◽  
Optimum Design ◽  
Test Data ◽  
Design Methodology ◽  
Rotating Machinery ◽  
Vibration Absorbers ◽  
Mass Ratio ◽  
Rotating Machine ◽  
Lateral Modes ◽  
Tuning Frequency

Abstract Damped vibration absorbers can significantly reduce the amplitude of resonant motion. Normally, these devices are used on machinery that is non-rotating (stationary). However, as this paper demonstrates both analytically and experimentally, a damped absorber can be successfully applied on rotating equipment, particularly on vertical machines, to attenuate lateral resonances. To illustrate this application, a detailed analysis of the damped absorber is presented, focusing on mass ratio, tuning frequency, amount of damping, and speed effects. It is shown that an optimum design can be obtained for use on a rotating machine that parametrically differs from a non-rotating application. Test data is also given illustrating the effectiveness of the concept and design methodology on an actual machine. Recommendations are provided to guide the application of this technology on other rotating machines.

A Combinatory Design Methodology Dedicated to the Ball and Roller Screw Drives for Optimum Design

2010 ◽  
Author(s):  
Pierre Dupont
Keyword(s):  
Optimum Design ◽  
Design Methodology ◽  
Short Review ◽  
Optimization Techniques ◽  
Industrial Case Study ◽  
Endurance Strength ◽  
Memorial Symposium ◽  
Roller Screw ◽  
The One ◽  
User Friendly

Machine-tools, packaging units, lifting systems and also other heavy duty devices (f.e. used in steel casting technologies) employ advantageously screw drives (balls, re-circulating rollers, and planetary roller drives) as mechanical command elements (f.e. directly coupled to servo drives), especially for their high efficiencies (∼87 .. 98%) and “output force to input torque ratio”. After a short review of the most important checks (for Static and Endurance Strength, Life, Shocks resistance and also some Miscellaneous Effects due f.e. to Critical Speeds and Stress Concentrators) it will be described briefly a combinatory design methodology or “heuristics” which takes into account as the technical viability and reliability as well as the economical feasibility of the whole system line (included end bearings and transmission) leading to an “overall safety ratio matrix” and/or to “viability and reliability graphs” helping in such a way the designer to reach an “optimum design” by an overall helicopter view of his/her design(s). In terms of optimization techniques, this user friendly combinatory design methodology could be placed in the field of the “heuristic” ones. An industrial case study will illustrate that presentation. This presentation is also a continuation of the one given for the MS&T’09 occurring in PITTSBURGH, USA during the “Charles R. MORIN Memorial Symposium on Failure Analysis & Prevention” for the ASM International.

OPTIMUM DESIGN PROCESS OF VIBRATION ABSORBER VIA IMPERIALIST COMPETITIVE ALGORITHM

2012 ◽  
Vol 12 (03) ◽  
pp. 1250019 ◽  
Author(s):  
ROUHOLLAH HOSEINI ◽  
HAMZE SALEHIPOOR
Keyword(s):  
Optimum Design ◽  
Seismic Design ◽  
Design Methodology ◽  
Imperialist Competitive Algorithm ◽  
Design Solution ◽  
Vibration Absorber ◽  
Vibration Absorbers ◽  
Structural Vibrations ◽  
Multi Objective ◽  
Analytical Expressions

This paper deals with the optimum design of vibration absorbers utilized to reduce undesirable random vibrational effects that are originated in linear structures. Analytical expressions, for the case of nonstationary white-noise accelerations, are derived. The criterion is different from most conventional optimum design criteria, since it is based on minimizing the displacement or the acceleration variance of the main structure responses, without considering performances required against failure. In this study, in order to control the structural vibrations induced on a mechanical structure excited by nonstationary based acceleration random process, the MOO (multi-objective optimum) design of a vibration absorber has been developed in a typical seismic design problem. This has been performed using the modern imperialist competitive optimization algorithm for multi-objective optimization. Results demonstrate the importance of this method and show that the multi-objective design methodology provides a significant improvement in performance stability, giving a better control of the design solution choice. A numerical example of a vibration absorber for a multi degree of freedom (DOF) system is developed and the results are generated and compared for higher (DOF) systems using two types of modeling. Finally, the results of each of the two types are discussed.

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