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Currently active suspension system is more applicable than passive for improving the suspension performance, ensuring the stability and passenger safety in modern automotive suspension system. However, high energy consumption is one of the main disadvantages of implementing this system in real applications. In this paper, the energy consumption of electromagnetic actuators used for an active suspension system controlled by proportional-integral-derivative (PID), fuzzy adaptive PID, and neuron adaptive PID are investigated through simulation studies. Based on the energy consumption and the performance analysis, it has found that it is potential to develop a vibration energy recovery system to achieve the energy balance requirement in active suspension systems.

The EU has set out to reduce negative impacts from electricity generation on the environment, human health and towards our dependence on fossil fuels. As the fastest growing renewable source of electricity, photovoltaics plays an important role in the energy transition. The manufacturing of photovoltaic modules requires materials classified as critical, making them prone to supply disruptions. Although these materials are essential to the EU economy, they are not sufficiently recovered at the end of a photovoltaic module’s life. An alternative intermediate solution could be to extend the lifespan of existing modules, to slow down demand for these materials in the future. The aim of this study was to analyse the theoretical options and practical examples of product life extension strategies for photovoltaics. The R-Ladder was used as a guiding framework, which provided examples of life extension strategies. These include Reuse, Repair, Refurbishment, Remanufacture and Repurpose. Aspects for each of these strategies were analysed to find potential benefits and challenges related to four aspects: economics, environment, energy, and materials. The approach of this study includes a literature review to identify the life extension strategies discussed specifically for photovoltaics in the context of the circular economy. This was followed by a multi-case study on practical applications of Reuse, Repair and Repurposing of photovoltaic modules. Findings from literature and the case study were further supplemented with the insights from six experts. These experts had diverse backgrounds in research, manufacturing, and procurement to offer a variety of insights and perspectives on life extension strategies for photovoltaics. Finally, two scenarios were created for possible life extension pathways for used photovoltaic modules to illustrate the potential impacts compared to a commonplace premature replacement scenario. Economics and module performance are key factors in decision-making and acquisition of a photovoltaic ...

This deliverable includes the methodology in EnergyPROSPECTS for an in-depth study of energy citizenship. It features the criteria used for selecting the cases for indepth study, the list of cases selected for in-depth study as well as key research foci and empirical research questions.

The level of advancement in the understanding of the mechanical properties of volcanic rocks is comparatively lower than that of sedimentary rocks. As part of the SUCCEED Project (Synergetic Utilisation of CO2 Storage Coupled with Geothermal Energy Deployment), which aims to investigate the feasibility of injecting captured and produced CO2 into the reservoirs to enhance geothermal production and achieve permanent CO2 storage at the Hellisheiði Geothermal Field in Iceland, this experimental research provides significant insights into the petrophysical and mechanical properties of the volcanic rocks collected from surface outcrops. The subsurface in Hellisheiði is mainly built up of hyaloclastite formations and interglacial basaltic lavas. During a field campaign samples were collected in different outcrops, ensuring that the samples were of high quality and sufficiently diverse to enable comprehensive analysis. Four samples per block and rock type have been prepared from the collected blocks, and they have been subjected to different laboratory tests to evaluate their petrophysical properties, such as porosity, density, and permeability, and their geomechanical behavior, using Unconfined Compression Test (UCS), Active-Source Acoustic Test, and Splitting Tensile Strength Test. Additionally, laboratory experiments have been conducted to investigate the impact of rapid cooling on rock damage due to thermal fracturing. The results show that there are interdependent relationships between porosity, bulk density, ultimate strength, Young's modulus, and wave velocities that can be observed when considering average values per rock. The rocks studied showed a negative correlation between porosity and other parameters and a direct correlation between ultimate strength and Young's Modulus. When examining individual rock samples, no significant correlations were observed between porosity and other parameters, however, those correlations where evident when comparing between different rock types, emphasizing the importance of ...

Global endeavors to reduce emissions in the shipping industry are accelerating the interest in fuel cell systems. This paper explores the application of different fuel cell types (LT-PEMFC, HT-PEMFC and SOFC) in combination with different fuels (LH2, LNG,MeOH and NH3) in expedition cruise ships. An impact model is developed for the first design phase. The goal of this paper is to evaluate the impact of the combination of fuel cell system implementation and operational profile on expedition cruise vessels. Impact is expressed in ship size, capital cost, operational cost and emissions. The model takes into account: fuel storage, on-board fuel processing, fuel cell system characteristics, balance of plant components, fuel cost over operational lifetime and all onboard emissions. In the research, seven different fuel cell systems and three different hybridization strategies are considered. For the six best performing combinations of fuel cell system and hybridization strategy, the range, endurance and capacity requirements are systematically varied to determine whether the best performing option depends on these requirements. Finally, hybrid option 2 (using diesel generators to support during long transits) combined with a methanol fueled LT-PEMFC system results in the lowest newbuild price. This option does comply with emission regulations and CO2 goals for 2030. Hybrid option 2 combined with an LNG fueled LT-PEMFC system results in the lowest total cost (newbuild price and fuel cost). This option does comply with emission regulations, but does not meet CO2 goals for 2030. When it is desired to reach this CO2 target, hybrid option 2 with methanol fueled LT-PEMFC is also recommended from a total cost perspective. ; Marine Technology

River systems play an important role in the filling of sedimentary basins and record the history of external forcing processes, such as climate, tectonics and sea-level change, acting on them. They are potential reservoirs for oil, gas and water, and can host coal and placer mineral deposits. Because of the complex interplay between the external forcing processes, however, understanding of the genesis of the stratigraphy of river systems and interpreting the stratigraphy correctly is far from straightforward. Current conceptual models are oversimplified, and more insight into the impact of external forcing processes must be gained to improve these models. The aim of this study was to assess the impact of climate (i.e., discharge and sediment influx) on the development of the large-scale stratigraphic architecture of river systems, in isolation and in conjunction with sea-level fluctuations, through an analogue modelling approach. Analogue physical models reproduce the long-term average effects and products of the transport processes in a river system, rather than the transport processes themselves. An advantage of analogue modelling over numerical modelling is that it is hard to make the model fit preconceived notions about the results, making it possible to test and develop conceptual models. The impact of climate (i.e., discharge and sediment influx) on the large-scale stratigraphic architecture of river-delta-shelf-basin systems appears not to be as dominant as the impact of sea-level change, but it does significantly affect the smaller scale stratigraphic architecture, such as the relative size of systems tracts and the rate and extent of erosion. Furthermore, we found a fundamental difference between the impact of changes in discharge and the impact of changes in sediment influx on the yield and mass accumulation at the mouth of a river system. River systems can act as buffers for rapid changes in sediment influx, while they react very rapidly to changes in discharge. Thus, the small-scale stratigraphy at the river mouth is controlled mainly by changes in discharge, and the large-scale stratigraphy is controlled by changes in sediment influx (and sea-level fluctuations). Also, because the response of the river gradient to an increase in discharge is the opposite to its response to an increase in sediment influx (and vice versa), the mass accumulation at the river mouth, combined with the overall stratigraphic architecture of the system, can be used to constrain paleo-discharge and paleo-sediment influx scenarios. Finally, our experiments show that a complex stratigraphic architecture is not necessarily the result of complex forcing, but can result from very simple changes in discharge. To assess the development of the stratigraphy in physical models, a new method for processing the data obtained in the experiments was developed. Series of subsequent digital elevation models of the surface of the model are converted, using custom-made software, into synthetic three-dimensional stratigraphy, containing true isochronous surfaces. This data set contains the development of the system through time in three dimensions, and can be presented in various formats, such as geological maps, geological sections and Wheeler diagrams.

Musta hiili on yksi ilmaston muutokseen eniten vaikuttavimmista partikkeleista. Tyypillisiä lähteitä sille ovat pienpoltto, liikenne ja metsäpalot. Mustan hiilen vaikutus ilmastoon korostuu arktisilla alueilla, joilla se laskeutuu lumipinnoille ja edistää niiden sulamista. Musta hiili syntyy hapettomissa olosuhteissa erilaisista hiilivedyistä. Kaasumaiset hiilivedyt, kuten C2H2, C2H4 ja C6H6, kiinnittyvät toisiinsa ja muodostavat monirenkaisen aromaattisen hiilivedyn. Kun useita monirenkaisia aromaattisia hiilivetyjä yhdistyy, syntyy kiinteä nokipartikkelin ydin. Ydin kasvaa suureksi, haarautuneeksi ja huokoiseksi nokipartikkeliksi toisten nokipartikkeleiden törmätessä siihen. Tässä diplomityössä tutkittiin mustan hiilen syntymistä biomassan pölypoltossa, jossa hienoksi jauhetut kiinteät partikkelit poltetaan siihen suunnitellulla polttimella. Tutkimuksessa käytettiin ANSYS Fluent virtauslaskentaohjelmaa. Tehtiin CFD-mallinnus yksinkertaisesta C2H4 polttimesta, 120 kWth biomassan pölypolttoliekistä sekä 100 MWth biomassan pölypolttolämpölaitoksesta. C2H4 liekkiä mallinnettiin ja tuloksia verrattiin kirjallisuudesta löydettyyn validointidataan, jotta saataisiin ymmärrystä nokimallin toiminnasta. Biomassan pölypolton nokimallinnuksessa on haastavaa sisällyttää noen prekursorit biomassan pyrolyysituotteisiin. Noen prekursori C2H2 päätettiin sisällyttää pyrolyysituotteisiin ja sen pitoisuutta arvioitiin kirjallisuuden ja testimallinnusten perusteella. 120 kWth pölypolttoliekkiä mallinnettiin useilla eri C2H2 pitoisuuksilla ja noen muodostumista seurattiin ja verrattiin kokeelliseen dataan. Noen muodostumista täyden mittakaavan 100 MWth lämpölaitoksessa mallinnettiin pienen mittakaavan malleista opitulla tiedolla. Lämpölaitoksessa tehtiin paljon kokeellisia mittauksia BC Footprint mittauskampanjan aikana ja mallinnuksen tuloksia verrattiin kokeelliseen dataan. Mallinnuksia ja mittauksia tehtiin eri kuormilla. Integroimalla C2H2 biomassan pyrolyysituotteisiin, noen muodostumista voidaan mallintaa suuntaa antavasti. Pyrolyysituotteiden riippuvuus kemiallisesta kinetiikasta täytyy huomioida, jotta noen muodostumista voidaan mallintaa eri kuormilla. Suhteet mustan hiilen päästöissä mittauspisteiden välillä ovat yhteisymmärryksessä mallinnuksen kanssa, mutta pitoisuus on kertaluokkaa suurempi CFD-mallissa. CFD-malli pystyi mallintamaan noen minimipitoisuuden 1.25 mg/Nm3 kattilan pohjalla ja sen lisääntymisen pitoisuuteen 2.25 mg/Nm3 tyhjässä vedossa täydellä 100 MWth kuormalla. Vastaavat pitoisuudet kokeellisissa mittauksissa mittauskampanjan ajalta ovat keskimäärin 90 and 219 µg/Nm3. Mallinnuksesta oli apua kokeellisten tulosten tulkitsemisessa. Jatkotutkimuksia varten pyrolyysikoostumus täytyy huomioida tarkemmin, jotta menetelmällä voitaisiin mallintaa eri biomassojen palamista ja palamista eri polttimissa. Black Carbon (BC) is one of the most influential particles affecting on the climate change. Typical sources for BC are residential combustion, traffic and forest fires. The impact of BC on the climate is emphasized at the arctic regions, where it descends on the snow surfaces and increases the melting. BC is formed from various hydrocarbons at fuel rich conditions. Gaseous hydrocarbons, such as C2H2, C2H4 and C6H6, connect and form Polycyclic Aromatic Hydrocarbons (PAH). When multiple PAHs are combined, a solid BC nucleus is formed. The nucleus grows into a large, branched, porous soot particle as other soot particles collide into it. This thesis studied the formation of BC in pulverized biomass combustion, where finely ground solid particles are combusted with a specifically designed burner. A commercial Computational Fluid Dynamics (CFD) software ANSYS Fluent was used. CFD modeling was performed on a simple C2H4 burner, a 120 kWth pulverized biomass combustion flame and a 100 MWth pulverized biomass combustion boiler. The C2H4 flame was modeled and the results compared with the validation data obtained from literature, to gain an understanding of the soot formation modeling. It is challenging to integrate soot precursors into biomass devolatilization products, when modeling BC formation in pulverized combustion. BC precursor C2H2 was included in the devolatilization products, but its concentration had to be estimated based on the literature and test simulations. The 120 kWth pulverized combustion flame was modeled with different concentrations of C2H2 in the devolatilization products and the formation of BC was observed and compared with experimental data. BC formation in the 100 MWth full scale boiler was modeled with the help of information learned from the small scale CFD models. A large amount of experimental measurements were made at the heating plant during a BC Footprint measurement campaign and the results of the CFD model were compared with the experimental data. Modeling and measurements were carried out under different loads. By integrating C2H2 into the biomass devolatilization products, BC formation can be approximately modeled. Devolatilization products’ dependency on chemical kinetics need to be noticed in order to simulate BC formation under different loads. Relations in BC emissions between measuring points are in agreement with the experimental measurements, but the concentration is an order of magnitude higher in the CFD model. The model was able to predict minimum soot concentration of 1.25 mg/Nm3 at the bottom of the boiler increasing up to 2.25 mg/Nm3 towards the empty pass at full 100 MWth load. Corresponding experimental concentrations are 90 and 219 µg/Nm3 on average, respectively. Results of the CFD model were helpful in explaining the experimental results. For further studies, the devolatilization composition needs to be modeled more accurately in order to model BC formation from different biomasses and in different burners.