scholarly journals Reducing cost uncertainty in the drivetrain design decision with a focus on the operational phase

2020 ◽  
Author(s):  
Freia Harzendorf ◽  
Ralf Schelenz ◽  
Georg Jacobs
Keyword(s):  
Open Access ◽  
Evaluation Criteria ◽  
Design Stage ◽  
Design Phase ◽  
Early Design ◽  
Inherent Risk ◽  
Open Access Data ◽  
Operational Phase ◽  
Access Data ◽  
Early Design Phase

Abstract. In order to identify holistically better drivetrain concepts for onshore application, their operational behaviour needs to be considered at an early design phase. In this paper, a validated approach for estimating drivetrain concept-specific risk of unplanned maintenance based on open access data is presented. Uncertain influencing factors are described with distribution functions. This way, the poor data availability in the early design phase can be used to give an indication about the concept’s choice influence on the unplanned operational turbine behaviour. In order to get representative comparisons, Monte Carlo method is applied. This makes it possible to model the life of a fictional wind turbine based on the derived distributions. Technical availability and drivetrain influenced unplanned maintenance effort are defined as evaluation criteria. The latter is constituted by labour, material, and equipment expenses. By calculating the range of fluctuation of the evaluation criteria mean values, this approach offers an indication about the inherent risk in the operational phase induced by the drivetrain concept choice. This approach shows that open access data or expert estimations are sufficient for comparing different drivetrain concepts over the operational phase in an early design stage. The approach is applied on the five most common state-of-the-art drivetrain concepts. The comparison shows that the drivetrain concept without a gearbox and with a permanent magnet synchronous generator performs the best in terms of absolute unplanned maintenance effort over the lifetime as well as on the inherent risk. For future research, the influence of the maintenance strategy as well as site and park specific impacts on the unplanned concept behaviour should be included. For adapting this method to new concepts, a physically based approach could be developed which would make it possible to estimate probability distributions for the uncertain factors. Nevertheless, this approach will help to identify holistically better drivetrain concepts by being able to estimate the inherent risks in the operational phase.

scholarly journals Reducing cost uncertainty in the drivetrain design decision with a focus on the operational phase

2021 ◽  
Vol 6 (2) ◽  
pp. 571-584
Author(s):  
Freia Harzendorf ◽  
Ralf Schelenz ◽  
Georg Jacobs
Keyword(s):  
Open Access ◽  
Wind Turbine ◽  
Evaluation Criteria ◽  
Synchronous Generator ◽  
Design Phase ◽  
Early Design ◽  
Inherent Risk ◽  
Operational Phase ◽  
Access Data ◽  
Early Design Phase

Abstract. In order to identify holistically better drivetrain concepts for onshore wind turbine application, their operational behavior needs to be considered in an early design phase. In this paper, a validated approach for estimating drivetrain-concept-specific unplanned operational effort and risk based on open-access data is presented. Uncertain influencing factors are described with distribution functions. This way, the poor data availability in the early design phase can be used to give an indication of the concept's choice influence on the unplanned operational wind turbine behavior. In order to obtain representative comparisons, a Monte Carlo method is applied. Technical availability and drivetrain-influenced unplanned operational effort are defined as evaluation criteria. The latter is constituted by labor, material and equipment expenses. By calculating the range of fluctuation in the evaluation criteria mean values, this approach offers an indication of the inherent risk in the operational phase induced by the drivetrain concept choice. This approach demonstrates that open-access data or expert estimations are sufficient for comparing different drivetrain concepts over the operational phase in an early design stage when using the right methodology. The approach is applied on the five most common state-of-the-art drivetrain concepts. The comparison shows that among those concepts the drivetrain concept without a gearbox and with a permanent magnet synchronous generator performs the best in terms of absolute drivetrain-influenced unplanned operational effort over the drivetrain's lifetime as well as in terms of the inherent risk for the assumptions made. It furthermore makes it possible to give insights into how the different drivetrain concepts might perform in future applications in terms of unplanned operational effort. Exemplarily the impacts of higher torque density in gearboxes, a change to moment bearings and adjusted coil design in electrically excited generators have been analyzed. This analysis shows that the superiority of synchronous-generator concepts manifested in historic data is not entirely certain in future applications. Concluding, this approach will help to identify holistically better wind turbine drivetrain concepts by being able to estimate the inherent risks and effort in the operational phase.

Innovative design for sustainability

2020 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Ruochen Zeng ◽  
Abdol Chini ◽  
Robert Ries
Keyword(s):  
Embodied Energy ◽  
Design Stage ◽  
Design Phase ◽  
Design Development ◽  
Support Design ◽  
Content Type ◽  
Early Design ◽  
Proposed Model ◽  
Alternative Structure ◽  
Early Design Phase

PurposeAs green building movement is widespread throughout the world, low-energy building becomes the standard. A designer's selection of building systems and materials during early design phase becomes more important. It is essential that designers include embodied energy and emissions among other criteria they use in selecting materials during the design development phase of a building. The aim of this study is to develop a model to integrate the embodied energy, embodied emissions, and cost of the alternative structure and envelope systems of a building during the design development stage.Design/methodology/approachA conceptual model is proposed to integrate the embodied energy, embodied emissions, and cost of the alternative structure and envelope systems of a building. A case study is used to test the proposed model in predicting the embodied impacts and cost of structure and envelope systems for an educational building.FindingsThe proposed model can assist designers in making informed decisions at the early design stage and selecting alternative structure and envelope systems considering embodied impacts and costs.Social implicationsDesigners consider reducing embodied impacts of buildings during early design phase as an important social responsibility, especially for megaprojects, which have great impact on our daily life.Originality/valueDevelopment of a model that can be used to support design decisions regarding sustainable design (embodied energy and embodied carbon emissions) and costs of buildings in early design phase.

scholarly journals Housing information modelling for BIM-embedded housing refurbishment

2018 ◽  
Vol 16 (3) ◽  
pp. 299-314 ◽  
Author(s):  
Ki Pyung Kim ◽  
Kenneth Sungho Park
Keyword(s):  
Thermal Performance ◽  
Input Data ◽  
Information Model ◽  
Design Stage ◽  
Data Sets ◽  
Design Phase ◽  
Content Type ◽  
Information Modelling ◽  
Early Design ◽  
Early Design Phase

Purpose The purpose of this study is to identify building information modelling (BIM) input data sets within a BIM-embedded housing refurbishment process and enable construction professionals to use BIM as an information management platform for housing refurbishment projects. Design/methodology/approach A hypothetical case study using BIM tools for a housing refurbishment project is adopted to identify BIM input data sets to create a housing information model within a BIM system. Reliability of the research outcome is examined by conducting a comparative analysis between existing and simulated research outcomes. Findings This research identifies essential BIM input data sets during the early design phase. The importance of a well-integrated housing information model containing accurate as-built condition, cost and thermal performance information is essential to use BIM for housing refurbishment. BIM can be feasible for housing refurbishment when an information-enriched housing information model is constructed. Furthermore, the capability of BIM that can enable key project stakeholders to determine the most affordable refurbishment solution among various alternatives is identified as BIM can provide reliable cost estimations and thermal performance of refurbishment alternatives at the early design stage. Research limitations/implications The examined refurbishment processes and input data sets are confined to the early design phases as BIM use for housing refurbishment is limited. Practical implications This research will contribute to use BIM for housing refurbishment by providing essential BIM input data sets and BIM-embedded refurbishment processes. Originality/value This research reveals primary housing information data sets and BIM-embedded refurbishment processes at the early design phase.

Open source riverscapes: Analyzing the river corridor of the Naryn River in Kyrgyzstan based on open access data

2021 ◽  
Author(s):  
Florian Betz ◽  
Magdalena Lauermann ◽  
Bernd Cyffka
Keyword(s):  
Remote Sensing ◽  
Open Access ◽  
Large Scale ◽  
Data Sets ◽  
Hierarchical Systems ◽  
Geomorphological Mapping ◽  
Open Access Data ◽  
Access Data ◽  
River Corridors ◽  
River Corridor

<p>In fluvial geomorphology as well as in freshwater ecology, rivers are commonly seen as nested hierarchical systems functioning over a range of spatial and temporal scales. Thus, for a comprehensive assessment, information on various scales is required. Over the past decade, remote sensing based approaches have become increasingly popular in river science to increase the spatial scale of analysis. However, data-scarce areas have been mostly ignored so far despite the fact that most remaining free flowing – and thus ecologically valuable – rivers worldwide are located in regions characterized by a lack of data sources like LiDAR or even aerial imagery. High resolution satellite data would be able to fill this data gap, but tends to be too costly for large scale applications what limits the ability for comprehensive studies on river systems in such remote areas. This in turn is a limitation for management and conservation of these rivers.</p><p>In this contribution, we suggest an approach for river corridor mapping based on open access data only in order to foster large scale geomorphological mapping of river corridors in data-scarce areas. For this aim, we combine advanced terrain analysis with multispectral remote sensing using the SRTM-1 DEM along with Landsat OLI imagery. We take the Naryn River in Kyrgyzstan as an example to demonstrate the potential of these open access data sets to derive a comprehensive set of parameters for characterizing this river corridor. The methods are adapted to the specific characteristics of medium resolution open access data sets and include an innovative, fuzzy logic based approach for riparian zone delineation, longitudinal profile smoothing based on constrained quantile regression and a delineation of the active channel width as needed for specific stream power computation. In addition, an indicator for river dynamics based on Landsat time series is developed. For each derived river corridor parameter, a rigor validation is performed. The results demonstrate, that our open access approach for geomorphological mapping of river corridors is capable to provide results sufficiently accurate to derive reach averaged information. Thus, it is well suited for large scale river characterization in data-scarce regions where otherwise the river corridors would remain largely unexplored from an up-to-date riverscape perspective. Such a characterization might be an entry point for further, more detailed research in selected study reaches and can deliver the required comprehensive background information for a range of topics in river science.</p>

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