54 research outputs found
CFD simulation of the dispersion of exhaust gases in a traffic-loaded street of Astana, Kazakhstan
The aim of this paper is to consider one of the most traffic-loaded regions of Astana city
(Kazakhstan) and to determine the concentration of carbon-monoxide (CO) in the air
during the peak hours. CFD analysis based on the SolidWorks-EFD platform was used to simulate the dispersion of contaminants given the estimated emission rates and weather conditions at the crossroad of Bogenbay Batyr and Zhenis Avenues in Astana.
Turbulence prediction was based on k-ε model with wall functions. The governing
equations were discretized using the finite volume method and a 2nd order spatial
scheme. The mesh verification was based on 1% convergence criterion for a 50% of
mesh density increment; air pressure near the wall of a selected building was chosen as the parameter to control the convergence. Numerical results are presented for prevailing conditions during all 4 seasons of the year, demonstrating that the highest levels of CO are recorded in summer and reach the values up to 11.2 ppm which are still lower than the maximum level admitted for humans. Nevertheless, obtained results show that Astana is gradually becoming a city that is likely to reach the critical levels of pollutants in the nearest future if control measures are not taken with enough anticipation. As for a future work, it is proposed to perform in-situ validation of specific scenarios to check and support the results obtained with CFD and to develop then specific policies for tackling the problem before it becomes evident
Analysis of pollutant dispersion in a street canyon of Astana
Due to the steadily rising number of vehicles, atmospheric air pollution has become
one of the evident problems in main cities around the world. Astana, the capital city of Kazakhstan,
is not an exception with it current expansion and economic growth. In order to avoid the hazardous
consequences of automobile and industry pollution onto the residents' health of Astana, it is important
to analyze and monitor the conditions of atmospheric air in the city. The main objective of this research
project is to simulate and analyze the dispersion of vehicle pollutants (CO) at the crossroad of Zhenis
and Bogenbay streets using Computational Fluid Dynamics (CFD) tools based on SolidWorks-EFD
numerical platform. This particular place for the study is selected because of its relatively heavy traffic
load and its close location to many residential buildings
Design of small-scale tilt-rotor unmanned aerial vehicle
Unmanned Aerial Vehicle (UAV) is the aircraft without a human pilot aboard. UAVs
are subcategorized as RC Models, which are controlled by a pilot via transmitter-receiver system, and
Drones, which are fully autonomous. They are used for different military missions, such as surveillance
and reconnaissance. They are widening their use in civil areas, for example, search and rescue operations,
filmmaking, remote sensing of chemical leaks, crop spraying and monitoring in agriculture, etc. Most
of the UAVs are either of airplane (fixed-wing) type or copter (Vertical Take Off and Landing) type. The
aim of this project is to design the UAV that will combine the hovering abilities of multicopters with the
endurance of fixed-wing aircrafts
Design of small-scale tilt-rotor unmanned aerial vehicle
Unmanned Aerial Vehicle (UAV) is the aircraft without a human pilot aboard. UAVs
are subcategorized as RC Models, which are controlled by a pilot via transmitter-receiver system, and
Drones, which are fully autonomous. They are used for different military missions, such as surveillance
and reconnaissance. They are widening their use in civil areas, for example, search and rescue operations,
filmmaking, remote sensing of chemical leaks, crop spraying and monitoring in agriculture, etc. Most
of the UAVs are either of airplane (fixed-wing) type or copter (Vertical Take Off and Landing) type. The
aim of this project is to design the UAV that will combine the hovering abilities of multicopters with the
endurance of fixed-wing aircrafts
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Creating comparability among European neighbourhoods to enable the transition of district energy infrastructures towards positive energy districts
Planning the required energy infrastructure for the energy transition is a crucial task for various neighbourhood concepts, such as positive energy districts. However, energy planning often comes with the challenges of data shortages and a lack of comparability among solutions for different districts. This work aims to enable this comparability by introducing an approach for categorising districts according to parameters that are relevant for the planning of neighbourhood energy infrastructures. Four parameters (climate, floor space index, heating demand and share of residential buildings) and their respective ranges (bands) were derived from the literature. Additionally, this work visualised the combination of all parameter bands across Europe to conveniently showcase districts that are comparable according to the selected parameters. This approach and its visualisation could be used in urban planning to share knowledge from existing energy district projects with those planned in comparable districts
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D4.4 - Report on developed methodologies and models for techno-economic modelling of PEDs and the transition towards their realisation
Executive Summary:
In the light of urgent need for decarbonisation of the building sector, techno-economic modelling of energy systems is an essential part of the planning process of urban development. Positive Energy Districts (PEDs) should contribute to this transformation towards less carbon-intensive and more energy independent urban areas. Therefore, this report presents the techno-economic models that have been developed throughout the Smart-BEEjS project to determine the energy infrastructure required to transform current districts into PEDs.
This report reviews the existing models that focus on the district and neighborhood energy modelling (Section 2). The literature emphasises that existing models are not sufficient for PED planning, as PED analysis requires a large diversity of data inputs and have very specific modelling requirements. Moreover, it is important to further advance an integrated systems approach that brings together technoeconomic and social aspects with sufficient detail.
Four modelling approaches address four different sectors of the PED's energy infrastructure that needsto be included in the planning of the transition from exiting districts to PEDs. The electricity based system, including local renewable energy generation and electricity-based heating and cooling is covered by a mixed integer linear programming approach to guarantee an optimal technology portfolio while ensuring a positive energy balance (Section 3.1). The heating and cooling system is focusing on district solutions such as the 4th generation district heating/cooling with a mathematical approach (Section 3.2). The energy efficiency uptake of the building stock is addressed by agent based modeling (Section 3.3). Finally, the electric vehicle related charging infrastructure is modelled using statistics on real data (Section 3.4). Furthermore, as sector coupling is highly important these days, the interconnections of the presented models are drawn (Section 3.5). The models include important social factors such as affordability, inclusiveness and energy justice that is often not the focus of mainstream techno-economic models. As affordability, inclusiveness and energy justice are cornerstones of the PED concept, the models aim to address those values.
The combined model can holistically evaluate what energy infrastructure is needed to transition from current districts to high-performance PEDs
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D4.3 - Report on infrastructure requirements for developing sustainably PEDs,summarizing the outcome of the techno-economic modelling activities
Implementation of PEDs requires immense infrastructure investments in energy efficiency measures, energy generation, transformation and storage as well as in new mobility solutions. On the other hand, it is crucial to create affordable living arrangements despite the high costs of the aforementioned measures. Thus, this work aims to answer the overarching question of which infrastructure will be required to turn an existing neighbourhood into a PED. As existing districts in Europe are highly heterogeneous and, thus, difficult to analyse, this study uses a case study with a specific district archetype. To address this issue, this study utilises the district comparability tool, a framework created as part of the SMARTBEEjS project to enable technical comparability across districts in Europe. In addition, the cost of the necessary infrastructure is estimated, which leads to the discussion of inclusion and affordability issues as potential barriers of PEDs.
An integrated techno-economic modelling consisting of different modelling approaches for the power, heating and cooling and mobility sectors as well as demand-side measures are applied. Those include tailor-made mixed integer linear programming, synPro simulations, agent based modelling and statistical correlations. Using these modelling methods, several plausible transition scenarios are analysed based on the building, climate and socio-demographic data of an archetype district of Griesheim-Mitte in Frankfurt am Main (Germany).
The results show that envelope retrofitting is crucial to fulfil the PED requirement of energy positivity and to reduce the capacities of the energy generation and storage technology. Furthermore, the PED concept can be more economical than the business-as-usual scenario of importing the required energy. However, high upfront costs can be a barrier for less wealthy societies. This barrier needs to be reduced by public schemes or smart business models to avoid creating a neighbourhood concept that does not uphold the principles of energy justice and inclusion.
This study has its limitations in terms of the scope of the study. Only one district archetype (based on Griesheim-Mitte in Frankfurt am Main and relevant for districts in Nottingham and Amsterdam) is analysed. Further work could look into different archetypes and the transition scenarios for those. Moreover, not all scenarios, i.e. transition measures could be modelled quantitatively within the frame of this work. In particular, the waste heat from data centers in the selected district was not considered. Hence, applying industrial waste heat for powering district heat networks should be investigated more thoroughly in the future
Silver nanoparticle-coated "cyborg" microorganisms: Rapid assembly of polymer-stabilised nanoparticles on microbial cells
© The Royal Society of Chemistry. Fabrication of "cyborg" cells (biological cells with surfaces functionalised using a variety of nanomaterials) has become a fascinating area in cell surface engineering. Here we report a simple procedure for fabrication of polycation-stabilised 50 nm silver nanoparticles and application of these nanoparticles for fabrication of viable "cyborg" microbial cells (yeast and bacteria). Cationic polymer-stabilised nanoparticles electrostatically adhere to microbial cells producing an even monolayer on the cell walls, as demonstrated using enhanced dark-field microscopy, atomic force microscopy and microelectrophoresis. Our procedure is exceptionally fast, being completed within 20 min after introduction of cells into nanoparticle aqueous suspensions. Polymer-stabilised silver nanoparticles are highly biocompatible, with viability rates reaching 97%. We utilised "cyborg" cells built using bacteria and silver nanoparticles to deliver nanoparticles into C. elegans microworms. We believe that the technique described here will find numerous applications in cell surface engineering. This journal i
Surface-Enhanced Raman Scattering to Evaluate Nanomaterial Cytotoxicity on Living Cells
© 2016 American Chemical Society.The increasing number of reports about false positive or negative results from conventional cytotoxicity assays of nanomaterials (NMs) suggests that more reliable NM toxicity assessment methods should be developed. Here, we report a novel approach for nanotoxicity evaluation based on surface-enhanced Raman spectroscopy (SERS). Three model NMs were tested on two model cell lines and the results were validated by WST-1 cytotoxicity assay and annexin V-FITC/propidium iodide (PI) staining as apoptosis-necrosis assay. The localization of nanoparticles (NPs) in the cells and the cellular conditions upon NP incubation were visualized by transmission electron microscopy (TEM) and enhanced dark-field (EDF) microscopy. SERS revealed a broader view on the consequences of cell-NM interactions compared to the conventional cytotoxicity assays where only one aspect of toxicity can be measured by one assay type. The results suggest that SERS can significantly contribute to the cytotoxicity evaluation bypassing NM or assay component-related complications with less effort
What affects the neurovisualisational detection of ischemic stroke?
Introduction. The incidence of stroke is 2.5–3 cases per 1 000 population per year, mortality – 1 case per 1 000 population per year. According to various data, up to 20% of computed tomography (CT) scans performed on the first day do not reveal signs of an ischemic focus.Aim of the study. To assess the detectability of acute ischemia foci using CT, depending on the location of the foci, the timing of neuroimaging, the severity of stroke, and other indicators.Material and methods. We analyzed 100 cases of acute cerebrovascular accident (ACV) by ischemic type. The timing of the CT scan, glucose level, coagulogram parameters, NIHSS scores at admission, focus localization, the presence of atherosclerosis of the arteries of the head, and atrial fibrillation were taken into account. Patients were divided into two groups depending on the fact of detection of the focus during the primary tomographic examination. Repeated neuroimaging (magnetic resonance imaging) was performed in 54 patients.Results. In the “CT-negative” group, stem strokes predominated (p = 0.01), patients were younger (р = 0.038), and there were significantly more women than men (р = 0.00006). An increase in glucose over 8 mmol/l, on the contrary, was more often detected in the “CT-positive” group (14 cases in “CT-positive” against 5 cases in “CT-negative” group, p = 0.022). NIHSS scores ≥ 5 were found in 24 patients (47%) in the “CT-positive” group and in 13 patients (26.5%) in the “CT-negative” group (p = 0.034).Conclusions. Cases of stroke that are not detected on CT scan upon admission to the hospital are more common among women, with stem localization, are associated with low NIHSS scores. High glucose levels at admission is associated with the detection of ischemic foci during the initial CT examination
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