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Records with Subject: Environment
1973. LAPSE:2023.15764
Collection and Utilization of Indoor Environmental Quality Information Using Affordable Image Sensing Technology
March 2, 2023 (v1)
Subject: Environment
Keywords: affordable technology, indoor environmental quality, Internet of Things, Machine Learning, operative temperature, ventilation control
Incorporating Internet of Things (IoT) technology into the operation of buildings is expected to generate immense synergy, thereby saving energy and improving occupant comfort by overcoming the limitations of the existing system. Preventing operations in the absence of occupants can save energy, and the occupants’ preferred operating temperature should be used as the control set-point rather than the nominal temperature. In this study, IoT technology and image sensors are used to rapidly detect indoor environment changes, and a method is proposed to utilize air quality and thermal comfort as the control set-points. A real-time ventilation control algorithm is proposed based on the CO2 concentration calculated according to the number of occupants. To check the thermal comfort level, the real-time operating temperature estimated from the surface temperature data of the infrared array sensor is reflected in the comfort zone defined by the American Society of Heating, Refrigerating, and Ai... [more]
1974. LAPSE:2023.15758
Spatial Succession for Degradation of Solid Multicomponent Food Waste and Purification of Toxic Leachate with the Obtaining of Biohydrogen and Biomethane
March 2, 2023 (v1)
Subject: Environment
Keywords: dark fermentation, environmental contamination, food waste, methanogenesis, recycling, spatial succession, syntrophy
A huge amount of organic waste is generated annually around the globe. The main sources of solid and liquid organic waste are municipalities and canning and food industries. Most of it is disposed of in an environmentally unfriendly way since none of the modern recycling technologies can cope with such immense volumes of waste. Microbiological and biotechnological approaches are extremely promising for solving this environmental problem. Moreover, organic waste can serve as the substrate to obtain alternative energy, such as biohydrogen (H2) and biomethane (CH4). This work aimed to design and test new technology for the degradation of food waste, coupled with biohydrogen and biomethane production, as well as liquid organic leachate purification. The effective treatment of waste was achieved due to the application of the specific granular microbial preparation. Microbiological and physicochemical methods were used to measure the fermentation parameters. As a result, a four-module direct... [more]
1975. LAPSE:2023.15745
Wind Speed Forecasts of a Mesoscale Ensemble for Large-Scale Wind Farms in Northern China: Downscaling Effect of Global Model Forecasts
March 2, 2023 (v1)
Subject: Environment
Keywords: diurnal variation, global forecast downscaling, mesoscale ensemble system, wind power prediction, wind speed
To facilitate wind power integration for the electric power grid operated by the Inner Mongolia Electric Power Corporation—a major electric power grid in China—a high-resolution (of 2.7 km grid intervals) mesoscale ensemble prediction system was developed that forecasts winds for 130 wind farms in the Inner Mongolia Autonomous Region. The ensemble system contains 39 forecasting members that are divided into 3 groups; each group is composed of the NCAR (National Center for Atmospheric Research) real-time four-dimensional data assimilation and forecasting model (RTFDDA) with 13 physical perturbation members, but driven by the forecasts of the GFS (Global Forecast System), GEM (Global Environmental Multiscale Model), and GEOS (Goddard Earth Observing System), respectively. The hub-height wind predictions of these three sub-ensemble groups at selected wind turbines across the region were verified against the hub-height wind measurements. The forecast performance and variations with lead ti... [more]
1976. LAPSE:2023.15731
How Environmental Regulation, Digital Development and Technological Innovation Affect China’s Green Economy Performance: Evidence from Dynamic Thresholds and System GMM Panel Data Approaches
March 2, 2023 (v1)
Subject: Environment
Keywords: digital development, dynamic panel threshold model, environmental regulations, green economic performance, system GMM
Based on the background of China’s “carbon neutral” policy and the booming digitalization, how does environmental regulation affect green economy performance? The existing literature has studied the impact of energy consumption on green economic performance. However, the literature has ignored the impact of carbon dioxide emissions on China’s green economy performance. In this regard, this research uses the non-radial distance function (NDDF) to calculate the green economic performance of China’s prefecture-level cities, and uses the dynamic panel threshold model and the systematic GMM method to study the nonlinear impacts and mechanisms of environmental regulation, digital development, technological innovation, and industrial structure upgrade on green economic performance. The panel data set contains 228 Chinese cities from 2003 to 2019. The following findings are established: first, after adding carbon dioxide emissions to China’s green economy performance, the environmental perform... [more]
1977. LAPSE:2023.15728
Contribution of Road Transport to the Attainment of Ghana’s Nationally Determined Contribution (NDC) through Biofuel Integration
March 2, 2023 (v1)
Subject: Environment
Keywords: arable land requirement, biofuel integration, energy demand model, Ghana road transport, greenhouse gas emissions
Since the Paris Agreement in COP21, many countries around the world, including Ghana and Thailand, have established a Nationally Determined Contribution (NDC) to reduce greenhouse gas (GHG) emissions, with first update recently in COP26. With Ghana’s ongoing effort at COP26 to change its baseline to 2019, this study established a detailed Ghana vehicle ownership model with necessary transport parameters to construct an energy demand model to provide insight for reducing GHG emission contributions from road transport through biofuel (both bioethanol and biodiesel) potential by recourse to a Low Emission Analysis Platform (LEAP), with two scenarios of development from Thailand’s best practice for policy recommendation, which are alternative (ALT), with up to E20/B20, and extreme (EXT), with up to E85/B50, for new vehicles. In each case, energy demand and GHG emissions were analyzed from detailed data on Ghana’s transport sector to show potential benefit from biofuel usages. From Ghana’s... [more]
1978. LAPSE:2023.15722
On-Line Monitoring of Biological Parameters in Microalgal Bioprocesses Using Optical Methods
March 2, 2023 (v1)
Subject: Environment
Keywords: biological variables, microalgal cultivations, on-line monitoring, optical sensors, software sensors
Microalgae are promising sources of fuels and other chemicals. To operate microalgal cultivations efficiently, process control based on monitoring of process variables is needed. On-line sensing has important advantages over off-line and other analytical and sensing methods in minimizing the measurement delay. Consequently, on-line, in-situ sensors are preferred. In this respect, optical sensors occupy a central position since they are versatile and readily implemented in an on-line format. In biotechnological processes, measurements are performed in three phases (gaseous, liquid and solid (biomass)), and monitored process variables can be classified as physical, chemical and biological. On-line sensing technologies that rely on standard industrial sensors employed in chemical processes are already well-established for monitoring the physical and chemical environment of an algal cultivation. In contrast, on-line sensors for the process variables of the biological phase, whether biomass... [more]
1979. LAPSE:2023.15719
A Cost-Benefit Analysis of Bakhtiari Hydropower Dam Considering the Nexus between Energy and Water
March 2, 2023 (v1)
Subject: Environment
Keywords: Bakhtiari Dam, environmental impact assessment, hydro project, social-economic feasibility, water-energy-food nexus
Hydropower stations have supplied most of the green electricity in various parts of the world. Nonetheless, the economic profit of hydro-electricity lies beyond its social costs in many cases. Despite the short-term economic benefits of large dams, their sustainable pros and cons are doubted. This study aims to investigate the long-term profitability of large hydropower stations by considering the nexus between the environmental, economic, and social aspects. Much progress has been made in simplifying feasibility studies of hydropower stations by developing comprehensive software and models according to the United Nations Sustainable development goals. Developed by International Atomic Energy Agency (IAEA), the SimPacts has become one of the most frequently-used simple models to estimate the external costs of electricity generation since 2003. Hydropower’s Environmental Costs Analysis Model (HECAM) is a popular user-friendly version of the model that includes more details for benefits... [more]
1980. LAPSE:2023.15706
Data-Driven Optimal Design of a CHP Plant for a Hospital Building: Highlights on the Role of Biogas and Energy Storages on the Performance
March 2, 2023 (v1)
Subject: Environment
Keywords: biogas, carbon dioxide reduction, energy storages, high-efficiency CHP, optimal design, primary energy saving, sustainable development
Combined heat and power (CHP) generation plants are an assessed valuable solution to significantly reduce primary energy consumption and carbon dioxide emissions. Nevertheless, the primary energy saving (PES) and CO2 reduction potentials of this solution are strictly related to the accurate definition and management of thermal and electric loads. Data-driven analysis could represent a significant contribution for optimizing the CHP plant design and operation and then to fully deploy this potential. In this paper, the use of a bi-level optimization approach for the design of a CHP is applied to a real application (a large Italian hospital in Rome). Based on historical data of the hospital thermal and electric demand, clustering analysis is applied to identify a limited number of load patterns representative of the annual load. These selected patterns are then used as input data in the design procedure. A Mixed Integer Linear Programming coupled with a Genetic Algorithm is implemented to... [more]
1981. LAPSE:2023.15680
State of the Art of Technologies in Adaptive Dynamic Building Envelopes (ADBEs)
March 2, 2023 (v1)
Subject: Environment
Keywords: active and passive systems, Adaptive Dynamic Building Envelopes, adaptive façade, Energy Efficiency
The design of adaptive façades as complex systems that dynamically respond to weather conditions and occupants’ demands is rapidly increasing in modern constructions since they are highly energy efficient. Adaptive Dynamic Building Envelopes (ADBEs) exploit the benefits of technologies that manage the energy and mass transfer between building and outdoor environments actively and selectively. There is a wide range of technologies used in the design of ADBEs that differ from one another in terms of user controllability and the level of how active or passive their technologies are. This paper provides a systematic search in literature on the technologies devised in the ADBEs, specifying the most prevalent practices, and highlights the most cutting-edge research approximations. The analysis shows more than half of the studies use photovoltaics (PVs) in their design. Using mechanical ventilation and heat pumps were the next popular choices. Moreover, approximately half of the studies were... [more]
1982. LAPSE:2023.15669
Does Energy Community Membership Change Sustainable Attitudes and Behavioral Patterns? Empirical Evidence from Community Wind Energy in Germany
March 2, 2023 (v1)
Subject: Environment
Keywords: behavior change, community energy, Energy Efficiency, hierarchical logistic regression, pro-environmental behavior, Renewable and Sustainable Energy, social acceptance
Community energy is seen as a helping hand for local, decentralized energy transition. Besides the main goal of supporting the community-friendly and socially acceptable development of renewable energies, the hope is also that a pro-environmental influence on sustainability behavior will be triggered when joining a community energy project. An analysis of a survey among 16 community energy projects in Germany, with 565 completed questionnaires, shows that a certain part of the members pays more attention to their energy behavior and develop a more positive attitude towards a decentralized energy transition and citizen participation after joining the community energy project. Therefore, we can empirically support that climate protection projects, such as community energy, influence pro-environmental attitudes and behavior, but this does not apply equally to all population groups. Members with higher income and stronger interest in returns are less likely to change their behavior. Based... [more]
1983. LAPSE:2023.15666
Effect of Environmental Parameters on Streamer Discharge in Short Air Gap between Rod and Plate
March 2, 2023 (v1)
Subject: Environment
Keywords: breakdown characteristics, differential equations, environment, meteorological parameters, short gap, simulation analysis, streamer discharge
Environmental meteorological parameters (temperature, humidity, air pressure, etc.) have an important impact on short gap streamer discharge. Based on the streamer theory and particle continuity equation of gas discharge, a short gap streamer discharge simulation model is established, and the influence of environmental parameters on the dynamic development process of streamer discharge is simulated and analyzed. The short gap air gap discharge characteristics were tested in a self-made gas discharge chamber. The results show that at low humidity (relative humidity 80%), with the increase of humidity, the electron density of the streamer channel decreases, the field strength of the streamer head decreases, the development speed of the streamer slows down, and the gap breakdown voltage increase. With a decrease of gas pressure, the electron density of the streamer channel decreases, the field strength of the streamer head decreases, the development speed of the streamer increases, and th... [more]
1984. LAPSE:2023.15662
Energy Transition as a Response to Energy Challenges in Post-Pandemic Reality
March 2, 2023 (v1)
Subject: Environment
Keywords: case study, energy transition, global trends, grand challenges, pandemic, sustainable development, wild cards
The concept of energy transition has been adopted by national governments, international and regional organizations. The COVID-19 pandemic triggered increasing attention to climate policy, energy transition, and economic resilience. This paper looks at energy transition in selected countries with the use of case studies—China, the European Union, India, Russia, Saudi Arabia, and the United States. The aim of the study is to analyze the main approaches to the energy transition in these countries and the barriers which may influence this process. The study applies foresight methods such as trend monitoring, case study, and STEPE methods for barrier analysis. The outcomes include identification of energy priorities in the national context, key directions for future transformation, and selected countries’ approaches to the energy transition after the COVID-19 pandemic. All considered countries are taking measures for the energy transition, but the motives, pace, and priorities differ. Thei... [more]
1985. LAPSE:2023.15650
The Impact of Green Finance on Urban Haze Pollution in China: A Technological Innovation Perspective
March 2, 2023 (v1)
Subject: Environment
Keywords: enterprise ownership, green finance, haze pollution, technological innovation
Green finance integrates the concept of environmental governance into the financial industry, which is conducive to sustainable development. Applying the mediating effect model, this paper investigates the effect of green finance on urban haze pollution and explores the mediating role of technological innovation of enterprises between them. Based on a sample of 639 enterprises in China over 2016−2019, a significantly negative effect of green finance on urban haze pollution is found. An increase of one standard deviation in green finance decreases PM2.5 concentration by 8.8 μg/m3, ceteris paribus. Further, green finance may improve environmental quality by promoting technological innovation. Considering the heterogeneity of enterprise ownership, this mediating effect exists in non-state-owned enterprises, while it cannot be observed in state-owned enterprises. This study proposes a new solution for pollution: using green financial tools to promote environmentally friendly technological... [more]
1986. LAPSE:2023.15631
Enhancing Acceptance and Trust in Automated Driving trough Virtual Experience on a Driving Simulator
March 2, 2023 (v1)
Subject: Environment
Keywords: acceptance, advanced driver assistant systems (ADAS), automated driving (AD), driving school, driving simulator, expression of trust, NASA TLX, simulator case study, system usability scale
As vehicle driving evolves from human-controlled to autonomous, human−machine interaction ensures intuitive usage as well as the feedback from vehicle occupants to the machine for optimising controls. The feedback also improves understanding of the user satisfaction with the system behaviour, which is crucial for determining user trust and, hence, the acceptance of the new functionalities that aim to improve mobility solutions and increase road safety. Trust and acceptance are potentially the crucial parameters for determining the success of autonomous driving deployment in wider society. Hence, there is a need to define appropriate and measurable parameters to be able to quantify trust and acceptance in a physically safe environment using dependable methods. This study seeks to support technical developments and data gathering with psychology to determine the degree to which humans trust automated driving functionalities. The primary aim is to define if the usage of an advanced drivin... [more]
1987. LAPSE:2023.15628
Comparison of Selected Technologies to Improve the Quality of Exhaust Gases from Landfill Gas Combustion
March 2, 2023 (v1)
Subject: Environment
Keywords: catalyst, combustion, exhaust gases, landfill gas
This paper presents the results of research on exhaust gases from landfill gas combustion. The measurements were carried out in a reclaimed landfill in Kiełcz (a passive degassing system based on gas flare). The research concerned the effects of selected exhaust gas purification technologies (platinum catalyzer on a ceramic carrier, molecular sieve, copper(II) oxide) for the quality of exhaust gases, and their particulate matter content. This paper aims to indicate which catalytic systems are most suitable for this gas type and their most efficient positioning in the flue gas duct. Due to increasingly stringent emission standards, the outcomes presented in this article could be helpful for landfill owners who wish to avoid paying fines for not complying with applicable limits. The measurements were carried out using a flue gas analyser, a particulate matter analyser fitted with a probe, and four thermocouples connected with the data recorder. The research outcomes determined the percen... [more]
1988. LAPSE:2023.15621
eCooking Delivery Models: Approach to Designing Delivery Models for Electric Pressure Cookers with Case Study for Tanzania
March 2, 2023 (v1)
Subject: Environment
Keywords: clean cooking, delivery models, electric cooking, enabling environment, market system, modern energy cooking services, socio-economic and cultural context, Tanzania
This paper defines eCooking Delivery Models (eCDMs) as the activities, resources and actors needed to deliver modern electric cooking (eCooking) appliances to end-users in need of innovative clean cooking solutions in the Global South. We define the eCooking Market System (socio-economic and cultural context, the enabling environment, market chains, support services) which conceptualizes the real-world market factors and surrounding context related to enabling the uptake and sustained use of eCooking appliances by end-users. We also describe an approach to design eCDMs and identify the support services required to start and sustain the market delivery infrastructure. The eCDM concept and approach are demonstrated through designing eCDMs and support services for electric pressure cookers (EPCs) for two end-user segments in Tanzania: rural and peri-urban/urban customer segments. Research methods included: focus groups and workshops (12), household surveys (51), cooking demonstrations (11... [more]
1989. LAPSE:2023.15606
Thermo-Chemical Conversion of Microwave Selectively Pre-Treated Biomass Blends
March 2, 2023 (v1)
Subject: Environment
Keywords: combustion, heat production, microwave pre-treatment, peat, pellet blends, softwood, thermal decomposition, wheat straw
Possibilities of more efficient use of regional lignocellulosic resources (wood, wheat straw, peat) of different origin for an environmentally friendly energy production using selectively MW pre-treated blends of commercial wood or wheat straw pellets with raw peat pellets are studied. A hypothesis is proposed and tested that selective MW pre-treatment of wood or wheat straw pellets at the frequency 2.45 GHz and blending of MW pre-treated pellets with raw peat pellets can be used to enhance and control the thermo-chemical conversion of biomass blends. To test this hypothesis, a combined experimental study and mathematical modelling of the processes were performed. The thermo-chemical conversion of selectively activated blends was experimentally studied using a batch-size pilot device, which consists of a biomass gasifier and a combustor. To evaluate the effect of selective MW pre-treatment of biomass pellets on the thermo-chemical conversion of pre-treated blends, measurements of the k... [more]
1990. LAPSE:2023.15603
Environmentally Safe Technology to Increase Efficiency of High-Viscosity Oil Production for the Objects with Advanced Water Cut
March 2, 2023 (v1)
Subject: Environment
Keywords: chemical EOR, displacement efficiency, ecological technology, high viscosity oil, mathematical simulation, mobility ratio, oil extraction, oil recovery, polymer flooding
The depletion of conventional oil reserves creates a significant demand for the development and improvement of methods and technologies for the production of hard-to-recover oil. A huge potential for hard-to-recover oil in Western Siberia lies in the Pokur suite (PK). These deposits are characterized by high oil viscosity and, accordingly, early water breakthrough. This study identifies and substantiates an effective technology for oil production from such and similar deposits using polymer flooding. The obtained data are based on research of the geological structure, the main reservoir properties and those of its fluids, chemical and laboratory methods of analysis, and the results of mathematical and hydrodynamic modeling. According to the results of hydrodynamic modeling, the greatest technological effect of polymeric water flooding is observed in the model of collector permeability at 70 mD and above 1000 mD, but this technology is not recommended for reservoirs with an average perm... [more]
1991. LAPSE:2023.15562
Analysis of Gas-Turbine Type GT-009 M Low-Toxic Combustion Chamber with Impact Cooling of the Burner Pipe Based on Combustion of Preliminarily Prepared Depleted Air−Fuel Mixture
March 2, 2023 (v1)
Subject: Environment
Keywords: combustion chamber, economic effect, environmental safety, gas turbine engine, nitrogen oxides, steady burning
This article analyzes the mechanism of formation of the main components of harmful emissions characteristic of combustion chambers operating on conventional hydrocarbon fuels. The method of combustion of a preliminarily prepared depleted air−fuel mixture was chosen as the object of the study. This method of suppressing harmful emissions was implemented in the design of a low-toxic combustion chamber developed as applied to the GT-009 M type unit with impact cooling of the burner pipe and provides for stabilization of the main kinetic flame by means of a diffusion-kinetic and a standby burner device. The results of the calculations performed with regard to the operating conditions of the low-toxic combustion chamber at the nominal load of GT-009 M allow us to conclude that the practical use of combustion of a depleted, preprepared, fuel−air mixture in combination with diffusion-kinetic stabilization of combustion is promising. The topic of this article is related to the problem of ecolo... [more]
1992. LAPSE:2023.15560
Global Warming: Is It (Im)Possible to Stop It? The Systems Thinking Approach
March 2, 2023 (v1)
Subject: Environment
Keywords: albedo effect, climate change, GEAM, global economic activity model, global warming, greenhouse gases, Gulf Stream, thawing of the tundra
For some time, there has been a slow but gradual rise in the average temperature of the entire globe, a “global warming”, in fact, the result of human and natural processes that have been producing this phenomenon for decades. Since they are not directly perceived by individuals, these processes and their effects have been ignored for a long time, or at least not considered to be immediately harmful and dangerous. Global warming does not depend so much on solar radiation as it does on the greenhouse effect deriving from the continuous emission, by human activities and natural events, of greenhouse gases that accumulate in the atmosphere and form a barrier to the dispersion of heat produced by solar radiation. A good number of models exists to explain how global warming is produced, which are technical in nature and consider the production of greenhouse gases as the most important cause; however, they do not always analyze and justify the reasons for such emissions. Following the logic,... [more]
1993. LAPSE:2023.15555
Challenges in the EU Banking Sector as Exemplified by Poland in View of Legislative Changes Related to Climate Crisis Prevention
March 2, 2023 (v1)
Subject: Environment
Keywords: banking sector, environmental responsibility, ESG, ESG factors, non-financial reporting, sustainable finance
The activity and initiatives undertaken by financial institutions to protect the environment are now the goal of the evolution of the entire financial market. However, it is important not to ignore the legal issues and their implications, which to a large extent now permeate many financial decisions and affect the practices and behaviours of banks. The main objective of this paper was to identify the current condition of and ongoing developments in European Union legal regulations concerning Environmental, Social, Governance (ESG) and sustainable finance. An important aspect of this study was also to analyse the tools, legal instruments, standards and guidelines of the European Commission and the European Banking Authority (EBA) and those proposed by the international business environment in the area of non-financial reporting ESG disclosures in the EU banking sector as exemplified by Poland. In addition, this paper analyses the status of implementation of ESG-related requirements set... [more]
1994. LAPSE:2023.15548
Novel Centralized Pseudonym Changing Scheme for Location Privacy in V2X Communication
March 2, 2023 (v1)
Subject: Environment
Keywords: adapted pseudonym change scheme, authorization authority backup, privacy measurement in V2X wireless communications
Vehicular ad hoc networks allow vehicles to share their information for the safety and efficiency of traffic purposes. However, information sharing can threaten the driver’s privacy as it includes spatiotemporal information, and the messages are unencrypted and broadcasted periodically. Therefore, they cannot estimate their privacy level because it also depends on their surroundings. This article proposes a centralized adaptive pseudonym change scheme that permits the certificate’s authority to adjust the pseudonyms assignment for each requesting vehicle. This scheme adapts dynamically depending on the density of the traffic environment and the user’s privacy level, and it aims to solve the trade-off problem between wasting pseudonyms and Sybil attack. We employ a Knapsack problem-based algorithm for target tracking and an entropy-based method to measure each vehicle’s privacy. In order to demonstrate the applicability of our framework, we use real-life data captured during the interop... [more]
1995. LAPSE:2023.15543
Assessment of the Impact of the Addition of Biomethanol to Diesel Fuel on the Coking Process of Diesel Engine Injectors
March 2, 2023 (v1)
Subject: Environment
Keywords: biomethanol, combustion, diesel engine, engine performance, environmental protection, injection coking
The paper presents unique research results on the effect of coking of diesel engine injector nozzles powered by mixtures of 10%, 20% and 30% biomethanol and diesel fuel compared to the engine being supplied with pure diesel fuel. The test results, obtained from an experiment conducted in accordance with the ISO 15550-1 standard, show the legitimacy of using biomethanol as an additive to diesel fuel due to the lower coking effect of the injector nozzles, which has a positive impact on the reduction of pollutant emissions during engine operation. Regarding the CEC PF-023 test, the tendency to reduce the coking tendency increases the percentage of biomethanol additive to diesel fuel. With a 10% share of biomethnol, the average coking effect of the injectors is over 1% lower, but with a share of 30% of bio-methanol, the coking effect is nearly 2% lower.
1996. LAPSE:2023.15537
Development of a Hydraulic System for the Automatic Expansion of Powered Roof Support
March 2, 2023 (v1)
Subject: Environment
Keywords: hydraulic leg, hydraulic system, powered roof support, tests under real conditions, work automation
A mechanical support in a longwall complex requires proper supervision and control of operating parameters because it is responsible for the safety of machines and workers. Its main functions are to protect the excavation against the adverse effects of rock mass and to move it along with the operational progress of the shearer and the scraper conveyor. In the era of Industry 4.0 as well as green economy and sustainable development, the development of machines and devices included in the longwall complex is an important area of invention. When it comes to the mechanical support included in the longwall complex, the authors propose changes to the hydraulic control system. The main purpose of the work was to develop a system that can automatically expand the legs of the powered support. Tests were carried out under real conditions while equipping the support section with a prototypical hydraulic system and with a system monitoring the correct operation of the prototype. This article prese... [more]
1997. LAPSE:2023.15520
Loss Estimation and Thermal Analysis of a Magnetic Levitation Reaction Flywheel with PMB and AMB for Satellite Application
March 2, 2023 (v1)
Subject: Environment
Keywords: active magnetic bearing, brushless DC motor, finite element method, loss power, magnetic levitation reaction flywheel, passive magnetic bearing, thermal analysis
The magnetic levitation reaction flywheel (MLRW) is a novel actuator of spacecraft attitude control because of its significant advantages, including lack of friction and active suppression of vibration. However, in a vacuum environment, the poor heat dissipation conditions make it more sensitive to various losses and rises in temperature. Therefore, increasing temperature is the key issue for components used in space. In this study, the losses of the three kinds of heat-generating areas in the MLRW, namely, the passive magnetic bearing (PMB), the active magnetic bearing (AMB) and brushless DC motor (BLDCM), were analyzed and calculated. Based on the electromagnetic field theory, the loss model of PMB was proposed. Based on the finite element method (FEM) and Bertotti model, the loss power of the AMB and the BLDCM was obtained. The calculated loss values were brought into the FEM to calculate the temperature field distribution of the MLRW system. Then, the key factors affecting the heat... [more]
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