Thermal and Mechanical Design Guidelines and General Considerations for the Proper Design, and Location, of Various Types of Service Connections on Steam Surface Condensers

2015 ◽  
Author(s):  
Darren M. Nightingale
Keyword(s):  
Mechanical Design ◽  
Design Guidelines ◽  
Steam Turbines ◽  
Special Cases ◽  
Catastrophic Failures ◽  
Drain Fluid ◽  
Proper Design ◽  
Structural Failures ◽  
Operational Issues

The incorrect design and/or poor location of service connections on steam surface condensers can cause serious, often catastrophic, failures due to the inadequate dispersion of drain fluid energies. These failures often occur during a number of different operational scenarios, which in turn can cause condenser tube and/or structural failures, both of which can lead to the de-rating of steam turbines, or even complete unit shut downs. This paper includes the latest thermal and mechanical design guidelines and general considerations for the proper design, and location, of various types of service connections on steam surface condensers. The paper also includes considerations for a number of special cases; such as steam bypass, deaerating drains, heater drains, etc. Furthermore, examples of common operational issues are included, together with recommended modifications and upgrades to address typical service connection failures on existing condensers. A Case Study and some examples are also referenced.

scholarly journals A regularized hidden Markov model for analyzing the ‘hot shoe’ in football

2021 ◽  
pp. 1471082X2110080
Author(s):  
Marius Ötting ◽  
Groll Andreas
Keyword(s):  
Markov Models ◽  
Hidden Markov ◽  
Simulation Experiments ◽  
Hot Hand ◽  
Special Cases ◽  
Psychology And Economics ◽  
Likelihood Approach ◽  
Penalized Likelihood Approach ◽  
Hot Hand Effect

We propose a penalized likelihood approach in hidden Markov models (HMMs) to perform automated variable selection. To account for a potential large number of covariates, which also may be substantially correlated, we consider the elastic net penalty containing LASSO and ridge as special cases. By quadratically approximating the non-differentiable penalty, we ensure that the likelihood can be maximized numerically. The feasibility of our approach is assessed in simulation experiments. As a case study, we examine the ‘hot hand’ effect, whose existence is highly debated in different fields, such as psychology and economics. In the present work, we investigate a potential ‘hot shoe’ effect for the performance of penalty takers in (association) football, where the (latent) states of the HMM serve for the underlying form of a player.

scholarly journals Bioclimatic and Regenerative Design Guidelines for a Circular University Campus in India

2021 ◽  
Vol 13 (15) ◽  
pp. 8238
Author(s):  
Noemi Bakos ◽  
Rosa Schiano-Phan
Keyword(s):  
Construction Industry ◽  
Assessment Tool ◽  
Economic Benefits ◽  
Design Guidelines ◽  
University Campus ◽  
Design Strategies ◽  
Regenerative Design ◽  
Governmental Institutions ◽  
Social Environmental

To transform the negative impacts of buildings on the environment into a positive footprint, a radical shift from the current, linear ‘make-use-dispose’ practice to a closed-loop ‘make-use-return’ system, associated with a circular economy, is necessary. This research aims to demonstrate the possible shift to a circular construction industry by developing the first practical framework with tangible benchmarks for a ‘Circular University Campus’ based on an exemplary case study project, which is a real project development in India. As a first step, a thorough literature review was undertaken to demonstrate the social, environmental and economic benefits of a circular construction industry. As next step, the guideline for a ‘Circular University Campus’ was developed, and its applicability tested on the case study. As final step, the evolved principles were used to establish ‘Project Specific Circular Building Indicators’ for a student residential block and enhance the proposed design through bioclimatic and regenerative design strategies. The building’s performance was evaluated through computational simulations, whole-life carbon analysis and a circular building assessment tool. The results demonstrated the benefits and feasibility of bioclimatic, regenerative building and neighbourhood design and provided practical prototypical case study and guidelines which can be adapted by architects, planners and governmental institutions to other projects, thereby enabling the shift to a restorative, circular construction industry.

scholarly journals Creating a Market for Disability Specific Housing on Indigenous Land: A Case Study from Yarrabah, Australia

Buildings ◽  
2018 ◽  
Vol 8 (11) ◽  
pp. 160
Author(s):  
Kate Sarkodee ◽  
Andrew Martel
Keyword(s):  
Housing Stock ◽  
Design Guidelines ◽  
Capital City ◽  
Early Assessment ◽  
Care Needs ◽  
Housing Investment ◽  
For Profit ◽  
Disability Accommodation ◽  
Private Investors

Australia’s National Disability Insurance Scheme Specialist Disability Accommodation (NDIS SDA) program anticipates new, disability specific, housing stock being built by private investors incentivized by cash payments and rental income. To date, very few new SDA dwellings have been constructed and the majority of the research and analysis of the program’s potential has been in the context of apartment construction in major capital city markets in Australia. This paper uses a hypothetical case study of building SDA accommodation in a discrete regional Indigenous community, Yarrabah, in Queensland. It investigates underlying assumptions within the scheme, particularly around the relationship of land to investment outcomes, as well as cultural considerations. An important aspect is to test how effectively the design guidelines associated with the scheme translate into an appropriate built form that is culturally and environmentally appropriate in locations outside major urban centres. The results suggest that housing actors from the not-for-profit sector may benefit from the SDA at the expense of profit-driven, market-based housing developers, and that the SDA design categories offer limited flexibility for participants with changing care needs, potentially restricting resident continuity in occupancy and ongoing return on investment. The work offers an early assessment on the workability of the SDA in the context of housing investment in a new market for the private housing industry.

On Integration of Additive Manufacturing During the Design and Development of a Rehabilitation Robot: A Case Study

2015 ◽  
Vol 137 (11) ◽  
Author(s):  
Kaci E. Madden ◽  
Ashish D. Deshpande
Keyword(s):  
Additive Manufacturing ◽  
Neurological Disorders ◽  
Development Process ◽  
Mechanical Design ◽  
Rehabilitation Robotics ◽  
Critical Design ◽  
Rehabilitation Robots ◽  
Time Optimization ◽  
Hand Exoskeleton

The field of rehabilitation robotics has emerged to address the growing desire to improve therapy modalities after neurological disorders, such as a stroke. For rehabilitation robots to be successful as clinical devices, a number of mechanical design challenges must be addressed, including ergonomic interactions, weight and size minimization, and cost–time optimization. We present additive manufacturing (AM) as a compelling solution to these challenges by demonstrating how the integration of AM into the development process of a hand exoskeleton leads to critical design improvements and substantially reduces prototyping cost and time.

Development of a Design for Additive Manufacturing Worksheet for Medical Casts

2021 ◽  
Author(s):  
Heena Noh ◽  
Kijung Park ◽  
Kiwon Park ◽  
Gül E. Okudan Kremer
Keyword(s):  
Additive Manufacturing ◽  
High Strength ◽  
Design Guidelines ◽  
Operational Performance ◽  
Design For Additive Manufacturing ◽  
Trade Offs ◽  
Novice Designers ◽  
Criteria Importance ◽  
Design For Am

Abstract Traditional plaster casts often cause dermatitis due to disadvantages in usability and wearability. Additive manufacturing (AM) can fabricate customized casts to have light-weight, high strength, and better air permeability. Although existing studies have provided design for additive manufacturing (DfAM) guidelines to facilitate design applications for AM, most relevant studies focused on the mechanical properties of outputs and too general/specific design guidelines; novice designers may still have difficulty understanding trade-offs between functional and operational performance of various DfAM aspects for medical casts. As a response, this study proposes a DfAM worksheet for medical casts to effectively guide novice designers. First, important DfAM criteria and their possible solutions for medical casts are examined through a literature review to construct a basic DfAM framework for medical casts. Next, a scoring system that considers relative criteria importance and criteria evaluation from both functional and operational perspectives is developed to identify the overall suitability of a medical cast design for AM. A case study of finger cast designs was performed to identify the DfAM performance of the sample designs along with redesign requirements suggested by the worksheet. The proposed worksheet would be used to achieve rapid medical cast design by objectively assessing its suitability for AM.

Development of a Last Stage Blade Row Coupled by Damping Elements: Numerical Assessment of its Vibrational Behavior and its Experimental Validation During Spin Pit Measurements

2017 ◽  
Author(s):  
Christian Siewert ◽  
Frank Sieverding ◽  
William J. McDonald ◽  
Manish Kumar ◽  
James R. McCracken
Keyword(s):  
Structural Integrity ◽  
Mechanical Design ◽  
Vibration Response ◽  
Dynamic Loads ◽  
Steam Turbines ◽  
Response Level ◽  
Vibrational Behavior ◽  
Blade Row ◽  
Calculation Results ◽  
Last Stage

Last stage blade rows of modern low pressure steam turbines are subjected to high static and dynamic loads. The static loads are primarily caused by the centrifugal forces due to the steam turbine’s rotational speed. Dynamic loads can be caused by instationary steam forces, for example. A primary goal in the design of modern and robust blade rows is to prevent High Cycle Fatigue caused by dynamic loads due to synchronous or non-synchronous excitation mechanisms. Therefore, it is important for the mechanical design process to predict the blade row’s vibration response. The vibration response level of a blade row can be limited by means of a damping element coupling concept. Damping elements are loosely assembled into pockets attached to the airfoils. The improvement in the blade row’s structural integrity is the key aspect in the use of a damping element blade coupling concept. In this paper, the vibrational behavior of a last stage blade row with damping elements is analyzed numerically. The calculation results are compared to results obtained from spin pit measurements for this last stage blade row coupled by damping elements.

Mechanical Design for Accuracy of Linkage Servo Press for Near-Net Shape Forming

2018 ◽  
Author(s):  
Jing Tao ◽  
Huanan Qian ◽  
Suiran Yu
Keyword(s):  
Mechanical Design ◽  
Structure Design ◽  
Tolerance Allocation ◽  
Component Level ◽  
Eccentric Load ◽  
Servo Press ◽  
Near Net Shape ◽  
Net Shape Forming ◽  
Heavy Loads

The accuracy of machine is important to achieving highly accurate shapes. This paper is focused on mechanical design of highly accurate mechanical linkage servo press applicable to (near-)net shape forming. The effects of geometric errors, deformations under heavy loads and ram tilting are analyzed. A top-down design for accuracy approach is proposed: First, accuracy model for identification of inaccuracy-causing factors and their interlinking relations is developed. Then, based on this model, top accuracy index are decomposed and translated into structure design specifications at component level. Both analytic and simulation methods are employed for design for accuracy in aspects of dimensional and geometric tolerance allocation, stiffness synthesis and anti-eccentric load capability. A case study of mechanical design for accuracy of a six-linkage mechanical servo press is also presented to demonstrate and test the proposed design approaches.

Microstructure Sensitive Design with First Order Homogenization Theories and Finite Element Codes

2005 ◽  
Vol 495-497 ◽  
pp. 23-30 ◽  
Author(s):  
Surya R. Kalidindi ◽  
J. Houskamp ◽  
G. Proust ◽  
H. Duvvuru
Keyword(s):  
Finite Element ◽  
Inverse Problems ◽  
Mechanical Design ◽  
Materials Design ◽  
Mathematical Framework ◽  
First Order

A mathematical framework called Microstructure Sensitive Design (MSD) has been developed recently to solve inverse problems of materials design, where the goal is to identify the class of microstructures that are predicted to satisfy a set of designer specified objectives and constraints [1]. This paper demonstrates the application of the MSD framework to a specific case study involving mechanical design. Processing solutions to obtain one of the elements of the desired class of textures are also explored within the same framework.

A Computational Product Model for Conceptual Design Using SysML

2009 ◽  
Author(s):  
Stefan Wo¨lkl ◽  
Kristina Shea
Keyword(s):  
Product Development ◽  
Conceptual Design ◽  
Mechanical Design ◽  
System Development ◽  
Concept Design ◽  
Product Modeling ◽  
Product Model ◽  
Mechatronic Systems ◽  
Starting Point

The importance of the concept development phase in product development is contradictory to the level and amount of current computer-based support for it, especially with regards to mechanical design. Paper-based methods for conceptual design offer a far greater level of maturity and familiarity than current computational methods. Engineers usually work with software designed to address only a single stage of the concept design phase, such as requirements management tools. Integration with software covering other stages, e.g. functional modeling, is generally poor. Using the requirements for concept models outlined in the VDI 2221 guideline for systematic product development as a starting point, the authors propose an integrated product model constructed using the Systems Modeling Language (SysML) that moves beyond geometry to integrate all necessary aspects for conceptual design. These include requirements, functions and function structures, working principles and their structures as well as physical effects. In order to explore the applicability of SysML for mechanical design, a case study on the design of a passenger car’s luggage compartment cover is presented. The case study shows that many different SysML diagram types are suitable for formal modeling in mechanical concept design, though they were originally defined for software and control system development. It is then proposed that the creation and use of libraries defining generic as well as more complicated templates raises efficiency in modeling. The use of diagrams and their semantics for conceptual modeling make SysML a strong candidate for integrated product modeling of mechanical as well as mechatronic systems.

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