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Optimization model of solar cooling system with latent heat storage
Get PDFToday, the fastest growing end-use in the buildings sector is cooling demand, notes the International Energy Agency (IEA). In the last few years, the interest in solar cooling systems has been growing globally. Solar cooling systems are the next solution to meet the growing demand for air conditioning. The literature analysis shows that solar cooling systems mainly use single-stage absorption chillers, with water as the working fluid, and only a small fraction of them use phase change materials to improve heat storage. Based on previous studies on solar-assisted cooling systems, the use of phase change materials for thermal storage should be investigated.The paper will present a study of a solar cooling system with the optimized PCM thermal storage, with the aim of stabilizing the operation of heat storage, taking into account the volatility of solar energy, the impact of short-term operations and peak hours on the amount of heat produced. This means that the amount of electricity consumed to heat up the accumulation tank will be significantly reduced. The optimization model in simulation software will be performed to test solar cooling system with latent heat storage, with aim to investigate the efficiency of the developed latent energy storage and provide technical guidance for the implementation of such system in the practice. All indicators, including environmental impact and economic calculations, will be identified in order to determinate the specific systems for foresight market uptake
Solar shelter: Exploring architectural design input for industrially-crafted shading devices
Get PDFEuropean Cities are strongly affected by the Urban Heat Island effect and Climate change impacts in recent and future summer periods. As such, the integration of passive cooling strategies is of increasing importance for the overall AEC (Architecture-Engineering-Construction) domain. Amongst other strategies, one of the most prominent strategies is the timely deployment of shading devices. While the shading device constructions connected to the inside, interstitial position or exterior of transparent building envelope components is thus an important part of the building, little change can be observed in the principal design and technology of such shading elements. Moreover, target conflicts between shading device deployment and architectural appearance can be observed in European Cities. For instance, the ensemble protection of the Vienna City morphology was - for a long time - considered to be more important than potent shading devices.The present contribution presents the approach of an effort toward highly-esthetical, functional shading devices that provide - despite their architectural-design approach - a high degree of shading performance. Together with the window-building industry, four different shading device designs have been designed, developed and virtually tested. The design process was guided by critical reviews by domain experts and performance simulation efforts. We present the genesis of the four designs and their performance implications as a proof of concept that effective shading systems can be understood as part of the esthetics of a building and practical passive cooling device at the same time
Digitalising cities: A methodology to map evaluation requirements into robust and feasible data collection approaches
Get PDFThe sustainable development of cities relies on the implementation of multi-sectoral actions towards carbon neutrality, reducing the air pollutants emissions. The actions\u27 decision-making process for cities transformation should be supported by lessons learnt from previous interventions and KPIs (Key Performance Indicators). To do so, gathering real data becomes pivotal, complementing simulation tools (currently used), solving the inherent uncertainties due to assumptions. Data collection methodologies are then necessary, being the main driver for digital cities and providing better mechanisms for informed decision-making. Most of the cities still operate in silos and do not always implement the strategic plans supported with a digitalization of the municipal processes. Within this perspective, this paper presents a methodology to support cities in the preparation of monitoring programmes to collect real data in a robust and feasible manner. Taking the KPIs and the Smart Cities urban strategies into account, this paper concludes with some lessons learnt within cities to deploy monitoring approaches. From the city challenges to the review of the plans, all the process is driven by real data and KPIs. The methodology has been applied in the mySMARTLife project (Grant Agreement #731297) and deployed into the cities of Nantes (France), Hamburg (Germany) and Helsinki (Finland)
Prvok - Issue on 3D printing concrete building
Get PDFPrvok is the first 3D printed concrete floating house in the Czech republic. Additive manufacturing - 3D printing became a synonym of sustainable building of the 21st century. Its experimental manner and lack of world\u27s standardisation ISO approvals hold the 3D printing concrete method on the edge of usability and applicability and stop a broader spread of application in practice. Furthermore, the used material was newly developed cement composite prefabricated mixture mady by Master Builder Solutions with polypropylene plastic micro-fibres, which was not previously tested in large structures. What we achieved, was a practical realisation of a 3D printed fully equipped and functioning concrete house as a habitable statue for a public event. In order to fulfil the request on insulation and avoiding heat bridges together with investing least material possible, we parametrically designed and implemented a wall system of construction. In order to be able to open the structure to the public, we tested it on the universal loading machines at the Faculty of civil engineering CTU Prague in scale 1:1. Testing fragments of the walls were also part of the research goals, which led us to the final design. In this paper, we present the results of the experiment together with the experimentally obtained data
Modelling of fission gas release in UO2 doped fuel using transuranus code
Get PDFThe expected benefits from Cr-doped fuel are improved retention of fission gases within the pellets due to its large grain size. To demonstrate this, several experiments have been carried out by Halden reactor and Studsvik. These experiments are now being used to benchmark several fuel performance codes among them transuranus code. All this as part of a Coordinate Research Project (CRP) by IAEA named Testing and Simulation for Advanced Technology and Accident Tolerant Fuels (ATF-TS). This work is introducing a novel fission gas diffusivity model for doped fuel in transuranus code. It is observed the benefits of introducing this new model when comparing to the standard model already existing in transuranus. Nevertheless, more work needs to be carried out to fully understand all the phenomena involved in adding dopant in UO2 due to change of thermo mechanical properties
On the ongoing computation of the LVR-15 reactor fuel burnup
Get PDFIsotopic composition of the LVR-15 reactor fuel changes significantly during the operation time. In order to enable Monte Carlo calculations of the LVR-15 core throughout any reasonable time period, the isotopic compositions of partially depleted fuel assemblies have to be known at the start of the simulation. Even though the infinite lattice calculation can represent useful initial approximation, the non-leakage assumption is not necessarily valid for compact and highly heterogenous cores like in case of the LVR-15. Therefore, a more advanced calculation process have to be implemented towards appropriate determination of fuel assembly burnup. The main aim of this paper is to describe the current state of the ongoing computation as well as provide an explanation of the chosen calculation scheme of the LVR-15 operation history. Currently available results that are affected by profound inaccuracy are discussed in the final part alongside with planned future improvements
Reactor criticals and spent fuel systems similarities
Get PDFMany conservative assumptions for subcriticality assessment calculations have to be made in current calculations of spent fuel storage systems. This is due to a fact that there is no available database of benchmarks containing spent fuel or materials with isotopic composition like spent fuel. However one potential source of spent fuel system experiments is being omitted – there are hundreds of commercial reactors around the world containing spent fuel on some level of burnup. These reactors have to be tested for safety reasons in the beginning of each cycle and parameters of these test states are well known.In this paper a possibility of using commercial reactor critical states for code validations and for subcriticality assessments of storage systems is discussed and potential approach for criticality safety analysis is given
Augmented reality to support parcel handling in last-mile logistics
Get PDFWe have developed an augmented reality (AR) based system which keeps track of events during the parcel handling process for last-mile logistics. The system can retrieve and highlight the location of parcels in large piles with AR on the user\u27s smartphone. A camera array automatically detects the parcels laid down manually by an operator. New parcels are scanned and parcel fingerprints are generated semi-automatically. The system can detect and track the known parcels by fingerprint and can further highlight the location of the parcel using 3D visual clues, directly on the smartphone of the operator
Environmental performances evaluation through building information models
Get PDFThe construction industry produces several negative environmental impacts. To promote solutions that reduce these negative impacts, it is crucial to increase awareness among all parties involved in the supply chain. Currently, certification protocols, environmental labels and declarations are the most common tools for promoting sustainability in the construction industry. However, these tools are generally non-mandatory and require specific competencies to thoroughly understand and interpret their outputs, especially for non-specialized users in sustainability assessment. This paper presents a tool for visualizing environmental impacts directly through a Building Information Model, by assigning different colours to model objects according to their environmental performances. Understanding environmental performances data is thus more accessible to non-expert users. Unlike several BIM LCA integration studies that primarily focus on the needs of designers, this contribution considers the perspective of manufacturers. The developed tool focuses on building products and has been carried out with the Autodesk Revit BIM authoring platform and its VPL-based Dynamo plug-in. Through the combination of 3D models and histograms, the tool facilitates manufacturers to visualize with real time updates which phase of a product life cycle requires sustainable innovation, which sub components or process determine the major environmental impacts and calculate the environmental cost indicator of a product
Analyses of the geometrical properties of fine recycled aggregates
Get PDFThe acquisition of natural sand and dumping of fine recycled aggregates (FRA) are two serious environmental problems that can be solved simultaneously by using FRA as replacement of natural sand in high-end applications. In the past, FRA has been considered an unwanted by-product of construction and demolition waste (CDW) processing, due to the high levels of contaminations and high content of fines. However, FRA is currently considered as a new secondary raw material with large potential. Due to the increasing interests in FRA it is of utmost importance to extensively examine their characteristics. To date, research has been done on the water absorption, density, chemical and mineralogical composition, and size distribution of the FRA. However, knowledge on the geometrical properties of FRA is limited. In this paper the geometrical properties of several types of FRA are examined using digital image processing (DIP). The effect of processing methods, crusher openings and crushing cycles are considered to gain new insights into the characteristics of FRA