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Records with Subject: Process Design
587. LAPSE:2023.28187
Assessing Hyperloop Transport Optimizing Cost with Different Designs of Capsule
April 11, 2023 (v1)
Subject: Process Design
Keywords: AutoCAD, capacity, capsule, Energy, hyperloop, optimizing cost, solar panel
Hyperloop technology is a transport mode designed to move passengers anywhere in the world, using electric propulsion to carry passengers through a vacuum/near-vacuum tube for a maximum speed of 1200 km/h. Given this, governments, engineers, researchers, and billionaires have been racing over the past years to obtain the first operational system in the world off the ground and bring it from concept to reality. The paper aimed to maximize the capacity of the Hyperloop’s capsule and identify a suitable design of Hyperloop technology based on the different capacities and speeds of the capsules as well as the assumptions of the initial annual demand. Additionally, significant attention will be paid to the interior design of the capsules in which people travel to make the journey more comfortable and enjoyable. The design will be conducted in AutoCAD and Autodesk Revit models based on the allocation of different components such as capacity, compressor fan, batteries, compressor motor, etc.... [more]
588. LAPSE:2023.28186
Fatty Acid Alkyl Ester Production by One-Step Supercritical Transesterification of Beef Tallow by Using Ethanol, Iso-Butanol, and 1-Butanol
April 11, 2023 (v1)
Subject: Process Design
Keywords: 1-butanol, Ethanol, fatty acid butyl ester, fatty acid ethyl ester, iso-butanol, supercritical, transesterification, waste beef tallow
The effect of temperature was studied on the synthesis of fatty acid alkyl esters by means of transesterification of waste beef tallow using ethanol and, iso-butanol and 1-butanol at supercritical conditions. These alcohols are proposed for the synthesis of biodiesel in order to improve the cold flow properties of alkyl esters. Alcohol−beef tallow mixtures were fed to a high-pressure high-temperature autoclave at a constant molar ratio of 45:1. Reactions were carried out in the ranges of 310−390 °C and 310−420 °C for ethanol and iso-butanol, respectively; meanwhile, synthesis using 1-butanol was assessed only at 360 °C. After separation of fatty acid alkyl esters, these samples were characterized by nuclear magnetic resonance (NMR) and gas chromatography coupled to mass spectrometry (GC-MS) to quantify yields, chemical composition, and molecular weight. Results indicated that yields enhanced as temperature increased; the maximum yields for fatty acid ethyl esters (FAEEs) were attained... [more]
589. LAPSE:2023.28177
Effect of the Mixer Design Parameters on the Performance of a Twin Paddle Blender: A DEM Study
April 11, 2023 (v1)
Subject: Process Design
Keywords: batch mixing, Discrete Element Method (DEM), impeller design, particle mixing, twin paddle blender
The design parameters of a mixing system have a major impact on the quality of the final product. Therefore, identifying the optimum parameters of mixing systems is highly relevant to various industrial processes dealing with particulate flows. However, the studies on the influences of the mixer’s design features are still insufficient. In this study, the Discrete Element Method (DEM) is used to examine the impact of paddle angle, width, and gap on the mixing performance of a twin paddle blender. The mixing performance and particle flow are assessed using the relative standard deviation (RSD) mixing index, velocity field, diffusivity coefficient, granular temperature, the force acting on particles, and the mixer’s power consumption. The mixing performance is highest for a paddle angle of 0° at the cost of the highest forces acting on particles. The paddle width is indicated as a critical factor for achieving better mixing quality. In contrast, the powder mixing efficiency and the mixer... [more]
590. LAPSE:2023.28163
Development of Agar Substitute Formulated with Mucilage and Pectin from Opuntia Local Waste Matter for Cattleya sp. Orchids In Vitro Culture Media
April 11, 2023 (v1)
Subject: Process Design
Keywords: local waste-based culture media, nopal hydrocolloids, Orchid, plant tissue culture media
The technology for reproducing orchids in vitro has had to evolve due to the demand for these plants and the high cost of the biotechnology used due to the agar, the gelling agent. Consequently, research has tended to search for natural substitutes for agar. Our work describes the use of pectin and mucilage hydrocolloids extracted from the local waste matter of two species of Opuntia (O. ficus-indica and O. robusta) to study as a gelling agent in vitro culture media for Cattleya sp. These hydrocolloids were obtained by alkaline hydrolysis. Subsequently, these were used in proportions of 0.8%, 0.6%, 0.4%, and 0.2% in combination with agar to study the gelation time, texture profile analysis (TPA), seed germination under light and dark conditions, and a phenological study, including orchid analyses of leaves and roots, root and leaf length, seedling height, and width of the best-designed treatment were studied. Our results demonstrate that the treatment composed of 0.4% O. ficus-indica p... [more]
591. LAPSE:2023.28130
Design and Evaluation of Regenerated Landscapes of Factory Sites Based on Evaluation Factors
April 11, 2023 (v1)
Subject: Process Design
Keywords: evaluation factors, indicator system, Kailuan system of industrial heritage, regenerated landscape
Research in the field of industrial heritage regeneration suffers from high subjectivity and low reliability in design and evaluation. The study takes seven regeneration projects of the Kailuan family of industrial heritage as examples, designs four optimisation and improvement strategies and constructs an evaluation system containing four intermediate layers and 23 indicator layers based on the evaluation factor method to realise the evaluation of design solutions. The average evaluation value of the four intermediate layers was approximately 0.65, and the average evaluation value of the 23 evaluation indicators was approximately 0.68. The evaluation values of the four intermediate layers for the seven Kailuan projects showed that the evaluation of the park and the evaluation of the participants’ perceptions were roughly higher than the standard values, while the evaluation of the buildings and the evaluation of the environmental image had lower evaluation values. The correlations bet... [more]
592. LAPSE:2023.28129
Dynamic Parameter Simulations for a Novel Small-Scale Power-to-Ammonia Concept
April 11, 2023 (v1)
Subject: Process Design
Keywords: Aspen Plus Dynamics®, dynamic process simulation, novel process design, power-to-ammonia
Ammonia is a promising carbon-free energy vector, hydrogen carrier, and efficient means for long-time hydrogen storage. Power-to-ammonia-to-power concepts, powered exclusively by electricity from renewable sources, will leave the carbon economy behind and enter a truly renewable era. However, the fluctuating nature of renewables requires a good dynamic behavior of such concepts. Employing the software Aspen Plus Dynamics®, this paper investigates the dynamic behavior of a novel containerized power-to-ammonia solution to be tested at the University of Genova in 2023. Implementing a novel kinetic reaction model, the impacts of several deviations from the optimal values of the cycle parameters are investigated. The simulations provide practical guidance on how to best and safely operate the cycle. A total of ten scenarios were simulated, of which six are acceptable, two are desirable, and two should be avoided. However, all scenarios can be safely controlled by the control infrastructure.
593. LAPSE:2023.28111
Sapo-34 Obtained from Amazonian Flint Kaolin: Influence of Impurities of “Oxidized Fe/Ti” in Synthesis and Its Application in the Removal of Cationic Dye from Water
April 11, 2023 (v1)
Subject: Process Design
Keywords: Adsorption, Amazonian kaolin, dye, SAPO-34, separation process
Non-processed kaolin (flint kaolin) from a mine located in the Capim area (Amazon region, northern Brazil), usually considered as waste, was selected as a source of silicon and aluminum in the synthesis of SAPO-34. This is a molecular sieve and cationic exchanger chosen for tests focusing on the removal of methylene blue in aqueous solutions, which is a cationic dye widely used by textile industries in Brazil. The results revealed that the SAPO-34 has been successfully synthesized with typical cubic morphology, good crystallinity (>90%), and thermal stability (~998 °C). Although the oxidized Fe/Ti impurities contained in the flint kaolin affect the degree of crystallinity of the zeolitic product, its adsorptive properties are not significantly affected, which demonstrates the excellent adsorption results (pH = 11; % removal > 90%). It proved to be an adsorbent with considerable adsorption capacity (9.83 mg·g−1). The pH test confirmed the acidic surface characteristics (pH solution 2−4;... [more]
594. LAPSE:2023.28083
Assessment of the Impact of Occupants’ Behavior and Climate Change on Heating and Cooling Energy Needs of Buildings
April 11, 2023 (v1)
Subject: Process Design
Keywords: climate changes, DesignBuilder, energy needs, occupant behavior, residential buildings, ventilation
Energy performance of buildings is a worldwide increasing investigated field, due to ever more stringent energy standards aimed at reducing the buildings’ impact on the environment. The purpose of this paper is to assess the impact that occupant behavior and climate change have on the heating and cooling needs of residential buildings. With this aim, data of a questionnaire survey delivered in Southern Italy were used to obtain daily use profiles of natural ventilation, heating, and cooling, both in winter and in summer. Three climatic scenarios were investigated: The current scenario (2020), and two future scenarios (2050 and 2080). The CCWorldWeatherGen tool was used to create the weather files of future climate scenarios, and DesignBuilder was applied to conduct dynamic energy simulations. Firstly, the results obtained for 2020 demonstrated how the occupants’ preferences related to the use of natural ventilation, heating, and cooling systems (daily schedules and temperature setpoint... [more]
595. LAPSE:2023.28058
Techno-Economic Assessment of Waste Heat Recovery Technologies for the Food Processing Industry
April 11, 2023 (v1)
Subject: Process Design
Keywords: baking, Energy Efficiency, food manufacturing, organic rankine cycle, vapour absorption cooling, waste heat recovery
The food manufacturing sector is one of the most dominant consumers of energy across the globe. Food processing methods such as drying, baking, frying, malting, roasting, etc. rely heavily on the heat released from burning fossil fuels, mainly natural gas or propane. Less than half of this heat contributes to the actual processing of the product and the remaining is released to the surroundings as waste heat, primarily through exhaust gases at 150 to 250 °C. Recovering this waste heat can deliver significant fuel, cost and CO2 savings. However, selecting an appropriate sink for this waste heat is challenging due to the relatively low source temperature. This study investigates a novel application of gas-to-air low temperature waste heat recovery technology for a confectionary manufacturing process, through a range of experiments. The recovered heat is used to preheat a baking oven’s combustion air at inlet before it enters the fuel-air mixture. The investigated technology is compared w... [more]
596. LAPSE:2023.28037
A Nonlinear Inverse Design Problem for a Pipe Type Heat Exchanger Equipped with Internal Z-Shape Lateral Fins and Ribs
April 11, 2023 (v1)
Subject: Process Design
Keywords: Levenberg–Marquardt method, nonlinear shape design problem, pipe type heat exchanger, Z-shape lateral fins with ribs
A non-linear three-dimensional inverse shape design problem was investigated for a pipe type heat exchanger to estimate the design variables of continuous lateral ribs on internal Z-shape lateral fins for maximum thermal performance factor η. The design variables were considered as the positions, heights, and number of ribs while the physical properties of air were considered as a polynomial function of temperature; this makes the problem non-linear. The direct problem was solved using software package CFD-ACE+, and the Levenberg−Marquardt method (LMM) was utilized as the optimization tool because it has been proven to be a powerful algorithm for solving inverse problems. Z-shape lateral fins were found to be the best thermal performance among Z-shape, S-shape, and V-shape lateral fins. The objective of this study was to include continuous lateral ribs to Z-shape lateral fins to further improve η. Firstly, the numerical solutions of direct problem were solved using both polynomial and... [more]
597. LAPSE:2023.27978
Evaluation of Two-Column Air Separation Processes Based on Exergy Analysis
April 11, 2023 (v1)
Subject: Process Design
Keywords: air separation, cryogenic distillation, exergy analyssis, exergy destruction, Exergy Efficiency, process simulation
Cryogenic air separation processes are widely used for the large-scale production of nitrogen and oxygen. The most widely used design for this process involves two distillation columns operating at different pressures. This work focuses on the selection of suitable cryogenic air separation process by evaluating seven alternative designs of the two-column air separation process based on detailed exergy analysis. The feed conditions (500 tons/h, and 50% relative humidity of air), product purities (99 mole% for both nitrogen and oxygen), and operational conditions (pressures of both distillation columns) are kept same in all designs. The two cryogenic distillation columns in each configuration are heat-integrated to eliminate the need for external utilities. Steady-state simulation results are used to calculate the exergy efficiency (%) of each equipment as well as its contribution toward the overall exergy destruction rate (kW) of the process. The results show that the compression sectio... [more]
598. LAPSE:2023.27914
The Saturated Water Content of Liquid Propane in Equilibrium with the sII Hydrate
April 11, 2023 (v1)
Subject: Process Design
Keywords: flow assurance, propane, structure type II hydrate, water content
In order to prevent solids from forming during the transportation and handling of liquid propane, C3H8(l), the fluid is dehydrated to a level below the water dew point concentration for the coldest operating temperature. Thus, accurate calculation of the saturation water content for C3H8 is important to determine the designed allowable concentration in liquid C3H8. In this work, we measured the water content of liquid C3H8 in the presence of the structure II hydrate from p = 1.081 to 40.064 MPa and T = 241.95 to 276.11 K using a tunable diode absorption spectroscopy technique. The water content results were modelled using the reference quality reduced Helmholtz equations and the Sloan et al. model for the non-hydrate and hydrate phases, respectively. Calculations show a good agreement (an average difference of less than 12 ppm) when compared to our measurements. Furthermore, the model was also used for calculating the dissociation temperatures for three phase loci, where a relative dif... [more]
599. LAPSE:2023.27880
Techno-Economic Analysis of Glazed, Unglazed and Evacuated Tube Solar Water Heaters
April 11, 2023 (v1)
Subject: Process Design
Keywords: evacuated tube, feasibility, glazed, solar water heater, subcontinent, unglazed
In the residential sector, a great part of the electricity goes into heating water by electric water heaters, which results in high CO2 emissions as well as an unprecedented increase in electricity demand leading to an energy crisis. This study offers solar water heaters as a more economical and efficient replacement for electric water heaters. The present study is aimed at investigating the potential for solar water heaters in the subcontinent, especially in India. A feasibility analysis is performed for seven cities in the subcontinent, namely Mumbai, New Delhi, Kolkata, Assam, Gujrat and Madhya Pradesh. Simulated results are based on a solar fraction, equity payback, multiple collectors (one, two or three), horizontal and tilted, type of collector (evacuated tube, glazed and unglazed), electricity saved and greenhouse gas (GHG) emission reduction. The collector’s area is made such that it should receive at least 50% of the solar fraction. The range of payback period varies from five... [more]
600. LAPSE:2023.27879
Coupling Hydrothermal Carbonization with Anaerobic Digestion for Sewage Sludge Treatment: Influence of HTC Liquor and Hydrochar on Biomethane Production
April 11, 2023 (v1)
Subject: Process Design
Keywords: anaerobic digestion, biochemical methane potential, biomethane, HTC liquor, hydrochar, hydrothermal carbonization, sewage sludge
The present study addresses the coupling of hydrothermal carbonization (HTC) with anaerobic digestion (AD) in wastewater treatment plants. The improvement in biomethane production due to the recycling back to the anaerobic digester of HTC liquor and hydrochar generated from digested sludge is investigated and proved. Mixtures of different compositions of HTC liquor and hydrochar, as well as individual substrates, were tested. The biomethane yield reached 102 ± 3 mL CH4 g−1 COD when the HTC liquor was cycled back to the AD and treated together with primary and secondary sludge. Thus, the biomethane production was almost doubled compared to that of the AD of primary and secondary sludge (55 ± 20 mL CH4 g−1 COD). The benefit is even more significant when both the HTC liquor and the hydrochar were fed to the AD of primary and secondary sludge. The biomethane yield increased up to 187 ± 18 mL CH4 g−1 COD when 45% of hydrochar, with respect to the total feedstock, was added. These results hi... [more]
601. LAPSE:2023.27822
Optimal Design of High-Frequency Induction Heating Apparatus for Wafer Cleaning Equipment Using Superheated Steam
April 11, 2023 (v1)
Subject: Process Design
Keywords: cleaning equipment, high frequency, induction heating (IH), LCL resonant network, superheated steam (SHS), titanium (Ti), wafer cleaning
In this study, wafer cleaning equipment was designed and fabricated using the induction heating (IH) method and a short-time superheated steam (SHS) generation process. To prevent problems arising from the presence of particulate matter in the fluid flow region, pure grade 2 titanium (Ti) R50400 was used in the wafer cleaning equipment for heating objects via induction. The Ti load was designed and manufactured with a specific shape, along with the resonant network, to efficiently generate high-temperature steam by increasing the residence time of the fluid in the heating object. The IH performance of various shapes of heating objects made of Ti was analyzed and the results were compared. In addition, the heat capacity required to generate SHS was mathematically calculated and analyzed. The SHS heating performance was verified by conducting experiments using the designed 2.2 kW wafer cleaning equipment. The performance of the proposed pure Ti-based SHS generation system was found to be... [more]
602. LAPSE:2023.27792
Operation of a Solid Oxide Fuel Cell Based Power System with Ammonia as a Fuel: Experimental Test and System Design
April 11, 2023 (v1)
Subject: Process Design
Keywords: ammonia, model, SOFC, stack test, system
Ammonia has strong potentialities as sustainable fuel for energy applications. NH3 is carbon free and can be synthetized from renewable energy sources (RES). In Solid Oxide Fuel Cells, NH3 reacts electrochemically thereby avoiding the production of typical combustion pollutants such as NOx. In this study, an ammonia-fueled solid oxide fuel cells (SOFC) system design is proposed and a thermodynamic model is developed to evaluate its performance. A SOFC short stack was operated with NH3 in a wide range of conditions. Experimental results are implemented in the thermodynamic model. Electrical efficiency of 52.1% based on ammonia Lower Heating Value is calculated at a net power density of 0.36 W cmFC−2. The operating conditions of the after burner and of the ammonia decomposition reactor are studied by varying the values of specific parameters. The levelized cost of energy of 0.221 $ kWh−1 was evaluated, as introduced by the International Energy Agency, for a system that operates at nomina... [more]
603. LAPSE:2023.27767
Techno-Economic Feasibility Analysis through Optimization Strategies and Load Shifting in Isolated Hybrid Microgrids with Renewable Energy for the Non-Interconnected Zone (NIZ) of Colombia
April 4, 2023 (v1)
Subject: Process Design
Keywords: hybrid microgrids, lead–acid batteries, lithium batteries, load shifting, Optimization
In developing countries, electrification in remote areas, where access to energy is limited or null, has been one of the biggest challenges in recent years. Isolated microgrids with renewable generation are an efficient alternative for the energy supply in these areas. The objective of this work was to analyse the techno-economic viability of 6 isolated microgrids in different locations in the non-interconnected zone of Colombia, considering different climatic conditions, the availability of renewable resources, the current consumption profile, and a modified profile applying demand-side management. Modelling and simulation were performed considering storage systems based on lithium and lead-acid batteries. The resulting simulations provide the optimal system cost, emissions levels, electricity cost and battery lifetime. This study demonstrates that isolated hybrid microgrids with renewable energy are a feasible alternative to solve access to energy problems, reducing the need for dies... [more]
604. LAPSE:2023.27766
Impact of Current Density and Cooling on the Weight Balance of Electrical Propulsion Drives for Aviation
April 4, 2023 (v1)
Subject: Process Design
Keywords: direct slot cooling, electrical aviation drives, high current density design, lightweight machine design, minimum weight, polysiloxan cooling fluids, surface cooler
Through applying an exemplary design study, the dependencies between current density, temperatures, and weight in an electrical drive system for a small range aircraft with conventional electrical fan or propeller drives are evaluated. This study applies a combined numerical (Finite Element Method FEM) and analytical approach to the machine design, calculation of temperatures, and cooling system design (cooler, pumps, piping). A design scenario was defined using start and climb flight in a warm tropical surrounding as the worst load case. The design has to move between two fixed temperature limits: The maximum allowable temperature in the machine insulation and the ambient temperature. The implemented method facilitates a comparatively fast-medium depth design of the drive system. The derived results show, in fact, a minimum of weight at a certain current density, which is one of the key interests for the designers of the electrical machine. The main influences on this minimum are the... [more]
605. LAPSE:2023.27757
Using Agent-Based Models to Generate Transformation Knowledge for the German Energiewende—Potentials and Challenges Derived from Four Case Studies
April 4, 2023 (v1)
Subject: Process Design
Keywords: agent-based model, energiewende, Energy, feedback products, insulation, power-to-fuels, retail market, transformation knowledge, transition
The German Energiewende is a deliberate transformation of an established industrial economy towards a nearly CO2-free energy system accompanied by a phase out of nuclear energy. Its governance requires knowledge on how to steer the transition from the existing status quo to the target situation (transformation knowledge). The energy system is, however, a complex socio-technical system whose dynamics are influenced by behavioural and institutional aspects, which are badly represented by the dominant techno-economic scenario studies. In this paper, we therefore investigate and identify characteristics of model studies that make agent-based modelling supportive for the generation of transformation knowledge for the Energiewende. This is done by reflecting on the experiences gained from four different applications of agent-based models. In particular, we analyse whether the studies have improved our understanding of policies’ impacts on the energy system, whether the knowledge derived is u... [more]
606. LAPSE:2023.27731
Methodology for Comprehensive Comparison of Energy Harvesting Shock Absorber Systems
April 4, 2023 (v1)
Subject: Process Design
Keywords: damping coefficient, design, EHSA, energy harvesting, methodology, shock absorber
In recent years, there has been a lot of work related to Energy Harvesting Shock Absorbers (EHSA). These devices harvest energy from the movement of the vehicle’s shock absorbers caused by road roughness, braking, acceleration and turning. There are different technologies that can be used in these systems, but it is not clear which would be the best option if you want to replace a conventional shock absorber with an EHSA. This article presents a methodology to compare the performance of different EHSA technologies that can replace a shock absorber with a given damping coefficient. The methodology allows to include different analysis options, including different types of driving cycles, computer vehicle models, input signals and road types. The article tests the methodology in selecting the optimal EHSA technology for a particular shock absorber and vehicle, optimizing at the same time energy recovery. In addition, a study of parameters in each type of technology is included to analyze... [more]
607. LAPSE:2023.27709
Design and Performance Analysis of a Saturated Iron-Core Superconducting Fault Current Limiter for DC Power Systems
April 4, 2023 (v1)
Subject: Process Design
Keywords: electromagnetic transient analysis, fault current limit, saturated iron-core superconducting fault current limiter, VSC-DC power system
A saturated iron-core superconducting fault current limiter (SI-SFCL) can significantly limit the magnitude of the fault current and reduce the stress on circuit breakers in direct current (DC) power systems. The SI-SFCL consists of three main parts: one magnetic iron-core, one normal conductive primary coil (CPC), and one superconducting secondary coil (SSC). This paper deals with the design options for the coil system of the SI-SFCL and confirms their operating characteristics through a physical experiment. The electromagnetic characteristics and operational features of the SI-SFCL was analyzed by a 3D finite element method simulation model. The design of the SSC was based on shape, wire types, required fault current limit and protection aspects. In the CPC, the bobbin was designed based on material selection, cost, structural design, and the effects of the SI-SFCL on the fault current limit. Based on these simulation results, a laboratory-scale SI-SFCL was developed, specifically fa... [more]
608. LAPSE:2023.27707
Biogas Upgrading Approaches with Special Focus on Siloxane Removal—A Review
April 4, 2023 (v1)
Subject: Process Design
Keywords: abatement techniques, adsorbents, biogas composition, biogas impurities, siloxane sources, volatile methylsiloxanes
Biogas, a product of anaerobic digestion process that consists mainly of methane and carbon dioxide is a suitable alternative fuel if unwanted impurities are removed as they have a negative impact on the equipment. The most significant technologically troublesome trace compounds that must be removed are siloxanes since they are converted into silica on gas surface engines and turbines resulting in equipment damage. The quality of the gas is certainly improved by reducing the amount of impurities and the end use determines the extent of biogas cleaning needed. The major aim of this study was to compile information that can assist researchers or even designers in selecting a suitable technology to remove siloxanes. Siloxane removal definitely can be achieved using different methods and the effectiveness of each method relies on careful consideration of the characteristics of both biogas and siloxane, as well as the technological aspects of the method. Herein, we review on different clean... [more]
609. LAPSE:2023.27643
Improving the Quality of Electricity in Installations with Mixed Lighting Fittings
April 4, 2023 (v1)
Subject: Process Design
Keywords: energy quality, harmonics components, light sources, power factor
The issues that are presented in the article concern the broadly understood parameters of the operation of lighting fixtures in mixed systems and the improvement of the quality of electricity, considered in two aspects: as receivers of the energy consumed, determining and generating reactive power, influencing the asymmetry of currents and the production of higher harmonics, determined by the parameters of current and supply voltage (independent of the consumers connected at the connection point), which are influenced by the consumers that are connected at the connection point. After the tests, in order to improve the quality of energy, a proprietary program for the design of passive resonance filters was developed. A wide range of measurements of various types of lighting devices was carried out in single, complex, and mixed systems. Luminaires with discharge and LED sources were selected for the analysis of energy parameters. The tests were carried out in accordance with the IEEE 145... [more]
610. LAPSE:2023.27627
Tailoring the Bore Surfaces of Water Hydraulic Axial Piston Machines to Piston Tilt and Deformation
April 4, 2023 (v1)
Subject: Process Design
Keywords: axial piston pump, surface shaping, water hydraulics
A novel virtual prototyping algorithm has been developed to design one of the most critical lubricating interfaces in axial piston machines of the swash plate type—the piston−cylinder interface—for operation with water as the working fluid. Due to its low viscosity, the use of water as a lubricant can cause solid friction and wear in these machines at challenging operating conditions. The prototyping algorithm compensates for this by tailoring the shape of the bore surface that guides the motion of each piston in this type of positive displacement machine to conform with the piston surface, taking into account both the piston’s tilt and its deformation. Shaping these surfaces in this manner can render the interface more conducive to generating hydrodynamic pressure buildup that raises its load-carrying capacity. The present work first outlines the structure of the proposed algorithm, then presents a case study in which it is employed to design a bore surface shape for use with two prot... [more]
611. LAPSE:2023.27612
An Assessment of Different Integration Strategies of Hydrothermal Carbonisation and Anaerobic Digestion of Water Hyacinth
April 4, 2023 (v1)
Subject: Process Design
Keywords: anaerobic digestion, biomethane, hydrochar, hydrothermal carbonization, process water, water hyacinth
Water hyacinth (WH) is an invasive aquatic macrophyte that dominates freshwater bodies across the world. However, due to its rapid growth rate and wide-spread global presence, WH could offer great potential as a biomass feedstock, including for bioenergy generation. This study compares different integration strategies of hydrothermal carbonisation (HTC) and anaerobic digestion (AD) using WH, across a range of temperatures. These include (i) hydrochar combustion and process water digestion, (ii) hydrochar digestion, (iii) slurry digestion. HTC reactions were conducted at 150 °C, 200 °C, and 250 °C. Separation of hydrochars for combustion and process waters for digestion offers the most energetically-feasible valorisation route. However, hydrochars produced from WH display slagging and fouling tendencies; limiting their use in large-scale combustion. AD of WH slurry produced at 150 °C appears to be energetically-feasible and has the potential to also be a viable integration strategy betw... [more]
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