scholarly journals Large Mass, Entry, Descent and Landing Sensitivity Results for Environmental, Performance, and Design Parameters

2010 ◽  
Author(s):  
Jeremy Shidner ◽  
Jody Davis ◽  
Alicia Cianciolo ◽  
Richard Powell ◽  
Jamshid Samareh
Keyword(s):  
Environmental Performance ◽  
Large Mass ◽  
Design Parameters

Influence of height of plate flow turbulizers on flow characteristics in microflow burners

2021 ◽  
pp. 51-61
Author(s):  
N. Fialko ◽  
◽  
V. Prokopov ◽  
N. Meranova ◽  
S. Aleshko ◽  
...  
Keyword(s):  
Mass Transfer ◽  
Environmental Performance ◽  
Flow Characteristics ◽  
Reacting Flows ◽  
Design Parameters ◽  
Circulation Flow ◽  
Absolute Value ◽  
Transfer Processes ◽  
Mass Transfer Processes ◽  
Combustion Processes

The use of flow turbulators in microflame burners is intended to intensify heat and mass transfer processes in the active combustion zone and, in general, to improve the energy and environmental performance of burners of this type. The available studies of various methods of intensifying combustion processes do not cover many issues related to the regularities of the influence of various factors on the characteristics of the working processes of microflame burners in the case of using one or another method of intensifying combustion. It is important to establish the dependence of these characteristics on various design parameters of the flow turbulators. The purpose of this study is to establish the patterns of influence on the flow characteristics of the height of the turbulizing plates located on the side surfaces of the flame stabilizers. The research was carried out on the basis of computer simulation using the FLUENT code. The results of the studies performed showed that with an increase in the height of the turbulizing plate from 0.005 to 0.01 m, there is a significant change in the flow pattern, which manifests itself in the lengthening of the circulation flow zones behind the flame stabilizer, in an increase in the maximum absolute value of the velocity in these zones, an increase in the level of velocity pulsations. and the size of the subregions in which these pulsations are significant, etc. Prospects for further research are related to the study of the considered situations in the conditions of reacting flows.

scholarly journals A Sensitivity Analysis Approach to Identify Key Environmental Performance Factors

2014 ◽  
Vol 2014 ◽  
pp. 1-9
Author(s):  
Xi Yu ◽  
Aicha Sekhari ◽  
Antoine Nongaillard ◽  
Abdelaziz Bouras ◽  
Suiran Yu
Keyword(s):  
Sensitivity Analysis ◽  
Life Cycle ◽  
Environmental Impacts ◽  
Environmental Performance ◽  
Product Life Cycle ◽  
Carbon Dioxide Emission ◽  
Circuit Board ◽  
Analysis Approach ◽  
Design Parameters ◽  
Performance Factors

Life cycle assessment (LCA) is widely used in design phase to reduce the product’s environmental impacts through the whole product life cycle (PLC) during the last two decades. The traditional LCA is restricted to assessing the environmental impacts of a product and the results cannot reflect the effects of changes within the life cycle. In order to improve the quality of ecodesign, it is a growing need to develop an approach which can reflect the changes between the design parameters and product’s environmental impacts. A sensitivity analysis approach based on LCA and ecodesign is proposed in this paper. The key environmental performance factors which have significant influence on the products’ environmental impacts can be identified by analyzing the relationship between environmental impacts and the design parameters. Users without much environmental knowledge can use this approach to determine which design parameter should be first considered when (re)designing a product. A printed circuit board (PCB) case study is conducted; eight design parameters are chosen to be analyzed by our approach. The result shows that the carbon dioxide emission during the PCB manufacture is highly sensitive to the area of PCB panel.

scholarly journals Air-Launch Experiment Using Suspended Rail Launcher for Rockoon

Aerospace ◽  
2021 ◽  
Vol 8 (10) ◽  
pp. 289
Author(s):  
Tadayoshi Shoyama ◽  
Ayana Banno ◽  
Yousuke Furuta ◽  
Noboru Kurata ◽  
Daisuke Ode ◽  
...  
Keyword(s):  
Elevation Angle ◽  
Large Mass ◽  
Design Parameters ◽  
Double Pendulum ◽  
Control Moment Gyroscope ◽  
Safety Issues ◽  
Control Moment ◽  
Pendulum Model ◽  
Frequency Components ◽  
Rigid Rod

The method of air-launching a rocket using a launcher suspended from a balloon, referred to as a rockoon, can improve the flight performance of small rockets. However, there have been safety issues and flight trajectory errors due to uncertainty with respect to the launch direction. Air-launch experiments were performed to demonstrate a rail launcher equipped with a control moment gyroscope to actively control the azimuth angle. As a preliminary study, it was suspended via a crane instead of a balloon. The rockets successfully flew along the target azimuth line and impacted the predicted safe area. The elevation angle of the launcher rail exhibited a fluctuation composed of two frequency components. A double-pendulum model with a rigid rod suspended by a wire was proposed to predict this behavior. Significant design parameters and error sources were investigated using this model, revealing the constraining effect of a large mass above the wire and elevation angle fluctuation, which caused trajectory errors due to the friction force on the rail guide and thrust misalignment. Finally, tradeoffs in designing the rail length were found between the launcher clear velocity and elevation fluctuations.

scholarly journals Integrated Environmental Design and Robotics Workflow for Double-Skin Facade Perforation Onsite

2021 ◽  
Author(s):  
Ahmed Khairadeen Ali ◽  
One Jae Lee
Keyword(s):  
Environmental Performance ◽  
Early Stage ◽  
Digital Design ◽  
Performance Criteria ◽  
Design Parameters ◽  
Stage Design ◽  
Performance Requirements ◽  
Double Skin ◽  
Early Stage Design ◽  
And Performance

In contemporary design practices, there is a disconnect between the design techniques used for early-stage design experimentation and performance analysis, and those used for the manufacture and construction. This study addresses the problems in developing an integrated digital design workflow and provides a research framework for integrating environmental performance requirements with robotic manufacturing processes on a construction site. The proposed method enables the user to import a design surface, identify design parameters, set several environmental performance goals, and thereafter simulate and select a robotic building strategy. Based on these inputs, design alternatives are developed and evaluated, considering their robotically simulated constructibility, in terms of their performance criteria. To validate the proposed method, the design is evaluated in an experiment wherein a double-skin facade perforation is generated using the proposed methodology. The results suggest a heuristic feature to improve the simulated robotic constructibility. Moreover, the functionality of the prototype is demonstrated.

A Strategy for Rapid Thermal Cycling of Molds in Thermoplastic Processing

2006 ◽  
Vol 128 (4) ◽  
pp. 837-843 ◽  
Author(s):  
Donggang Yao ◽  
Pratapkumar Nagarajan ◽  
Lei Li ◽  
Allen Y. Yi
Keyword(s):  
Thermal Cycling ◽  
Rapid Heating ◽  
Thermal Contact ◽  
Experimental Studies ◽  
Thermal Response ◽  
Large Mass ◽  
Design Parameters ◽  
Thermal Mass ◽  
Mold Surface ◽  
Shell Mold

Thermal cycling of molds is frequently desired in thermoplastic processing. Thermal cycling of the entire mold with a large mass, however, requires an exceedingly long cycle time. A processing strategy for mold rapid heating and cooling, involving a thin-shell mold and two thermal stations (one hot and one cold), was investigated. Because of its low thermal mass, the shell mold can be rapidly heated and cooled through heat conduction by selectively contacting with the two stations. Numerical simulations were performed to study the effect of different design parameters, including thermal contact resistance, shell material, and shell thickness, on the thermal response at the mold surface. Experimental studies showed aluminum shell molds with a thickness of 1.4mm can be rapidly heated from room temperature to 200°C in about 3s using a hot station at 250°C. The method was used for thermal cycling of embossing tools. Surface microfeatures can be rapidly transferred from thin metallic stamps to polymer substrates with cycle times less than 10s.

scholarly journals Double-Skin Facade Perforation Workflow Onsite Using Robot Arm

2021 ◽  
Author(s):  
Ahmed Khairadeen Ali ◽  
One Jae Lee
Keyword(s):  
Environmental Performance ◽  
Early Stage ◽  
Digital Design ◽  
Performance Criteria ◽  
Design Parameters ◽  
Robot Arm ◽  
Performance Requirements ◽  
Double Skin ◽  
Early Stage Design ◽  
And Performance

In contemporary design practices, there is a disconnect between the design techniques used for early-stage design experimentation and performance analysis, and those used for the manufacture and construction. This study addresses the problems in developing an integrated digital design workflow and provides a research framework for integrating environmental performance requirements with robotic manufacturing processes on a construction site. The proposed method enables the user to import a design surface, identify design parameters, set several environmental performance goals, and thereafter simulate and select a robotic building strategy. Based on these inputs, design alternatives are developed and evaluated, considering their robotically simulated constructibility, in terms of their performance criteria. To validate the proposed method, the design is evaluated in an experiment wherein a double-skin facade perforation is generated using the proposed methodology. Initial results suggest a heuristic feature to improve the simulated robotic constructibility. Moreover, the functionality of the prototype is demonstrated.

Ex-Post Analyses of Agri-Environment Schemes

2011 ◽  
pp. 23-38 ◽  
Author(s):  
Fabio Bartolini ◽  
David Bourke ◽  
John Finn ◽  
Davide Viaggi
Keyword(s):  
Environmental Performance ◽  
Single Case ◽  
Multicriteria Analysis ◽  
Evaluation Process ◽  
Environmental Data ◽  
Performance Criteria ◽  
Design Parameters ◽  
Ex Post ◽  
Environmental Objectives

This chapter illustrates an ex-post evaluation of the performance of agri-environment scheme (AES) implementation in three case study regions in the EU. Due to a lack of available environmental data, we devised a methodology to assess environmental performance of AESs in the case study areas. The methodology is based on the combination of a harmonised framework for characterising environmental objectives, expert judgement, aimed at assessing environmental effectiveness, and multicriteria analysis techniques, aimed at producing an aggregated judgement about single case studies. Our experience shows the potential practical application of this methodology, especially in formalising the evaluation process. In particular, the methodology connecting the evaluation process with design parameters helps to identify specific causes of lower effectiveness. The methodology could also be used to conduct an ex-ante evaluation (based on experts’ predictions of environmental performance criteria), and is especially suited to learning how to improve the environmental performance of schemes.

scholarly journals Performance Evaluation of Three Different Façade Models for Sustainable Office Buildings

2006 ◽  
Vol 1 (4) ◽  
pp. 89-103
Author(s):  
Matthias Haase ◽  
Alex Amato
Keyword(s):  
Environmental Performance ◽  
Driving Forces ◽  
Green Building ◽  
Building Design ◽  
Design Parameters ◽  
Building Projects ◽  
Green Building Design ◽  
Acoustic Comfort ◽  
Important Design ◽  
Comfort Criteria

Sustainable development issues are currently the driving forces of many building projects. The building façade is critical for the architectural expression and has a large affect upon large parts of the building's environmental performance. This study investigates the advantages of using multidimensional computer aided modeling and simulation to produce a sustainable façade design. A first step towards green building design is to establish a list of parameters which can then be used as design criteria, e.g. environmental performance, thermal visual and acoustic comfort, etc. Computer simulation and an analysis of recent projects in Hong Kong can help to determine the performance according to these design parameters whilst environmental impacts due to energy consumption are considered to be an important design parameter, it is also important for comfort criteria to be considered.

Open discussion

1982 ◽  
Vol 99 ◽  
pp. 605-613
Author(s):  
P. S. Conti
Keyword(s):  
Buenos Aires ◽  
Large Mass ◽  
List Type ◽  
Common Phenomenon ◽  
Open Discussion ◽  
The Stability ◽  
Ring Nebulae

Conti: One of the main conclusions of the Wolf-Rayet symposium in Buenos Aires was that Wolf-Rayet stars are evolutionary products of massive objects. Some questions:–Do hot helium-rich stars, that are not Wolf-Rayet stars, exist?–What about the stability of helium rich stars of large mass? We know a helium rich star of ∼40 MO. Has the stability something to do with the wind?–Ring nebulae and bubbles : this seems to be a much more common phenomenon than we thought of some years age.–What is the origin of the subtypes? This is important to find a possible matching of scenarios to subtypes.

The influence of confocal microscope design on imaging performance

1993 ◽  
Vol 51 ◽  
pp. 144-145
Author(s):  
C J R Sheppard
Keyword(s):  
Image Quality ◽  
Fluorescence Imaging ◽  
Confocal Microscope ◽  
Industrial Applications ◽  
Three Dimensions ◽  
Design Parameters ◽  
Weak Signals ◽  
Size And Shape ◽  
Imaging Performance ◽  
Fundamental Limitation

The confocal microscope is now widely used in both biomedical and industrial applications for imaging, in three dimensions, objects with appreciable depth. There are now a range of different microscopes on the market, which have adopted a variety of different designs. The aim of this paper is to explore the effects on imaging performance of design parameters including the method of scanning, the type of detector, and the size and shape of the confocal aperture.It is becoming apparent that there is no such thing as an ideal confocal microscope: all systems have limitations and the best compromise depends on what the microscope is used for and how it is used. The most important compromise at present is between image quality and speed of scanning, which is particularly apparent when imaging with very weak signals. If great speed is not of importance, then the fundamental limitation for fluorescence imaging is the detection of sufficient numbers of photons before the fluorochrome bleaches.

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