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Records with Subject: Process Design
Showing records 1 to 25 of 279. [First] Page: 1 2 3 4 5 Last
The Design of High Efficiency Crossflow Hydro Turbines: A Review and Extension
Ram Adhikari, David Wood
January 23, 2020 (v1)
Keywords: crossflow hydro-turbine, flow features, maximum efficiency, RANS simulation
Efficiency is a critical consideration in the design of hydro turbines. The crossflow turbine is the cheapest and easiest hydro turbine to manufacture and so is commonly used in remote power systems for developing countries. A longstanding problem for practical crossflow turbines is their lower maximum efficiency compared to their more advanced counterparts, such as Pelton and Francis turbines. This paper reviews the experimental and computational studies relevant to the design of high efficiency crossflow turbines. We concentrate on the studies that have contributed to designs with efficiencies in the range of 88⁻90%. Many recent studies have been conducted on turbines of low maximum efficiency, which we believe is due to misunderstanding of design principles for achieving high efficiencies. We synthesize the key results of experimental and computational fluid dynamics studies to highlight the key fundamental design principles for achieving efficiencies of about 90%, as well as future... [more]
Process Modeling, Optimization, and Heat Integration of Ethanol Reforming Process for Syngas Production with High H2/CO Ratio
Dong Xiang, Peng Li, Xiaoyou Yuan
January 19, 2020 (v1)
Keywords: ethanol reforming, heat integration, hydrogen production, system optimization
The process modeling, parameter optimization, and heat integration of reforming ethanol to hydrogen is conducted in this paper. Modeling results show that the optimum reaction pressure for ethanol steam reforming is 1 bar. When the 7.4:1 is selected as a moderate water/ethanol ratio, the optimum reaction temperature is about 755 °C. As for heat integration, the composite curve and optimum heat-exchange network are given out by pinch technology, of which adding a heat exchanger can reduce 10,833 kW of heating duty and 10,833 kW of cooling duty and make the energy saving reach about 57.4%. Another two heat-integration plans are proposed for the ethanol steam-reforming process, to further decrease the high-level heat duty. Finally, similar heat integration was also carried out for the oxidative steam reforming, and the system is autothermal when the oxygen/ethanol is about 0.5:1 on the basis of above steam-reforming process, while the hydrogen molar purity is decreased from 69% to 66%.
A Comprehensive Review and Technical Guideline for Optimal Design and Operations of Fuel Cell-Based Cogeneration Systems
Farah Ramadhani, Mohd Azlan Hussain, Hazlie Mokhlis
January 19, 2020 (v1)
Keywords: cogeneration, fuel cell, guidelines, optimal design, review
The need for energy is increasing from year to year and has to be fulfilled by developing innovations in energy generation systems. Cogeneration is one of the matured technologies in energy generation, which has been implemented since the last decade. Cogeneration is defined as energy generation unit that simultaneously produced electricity and heat from a single primary fuel source. Currently, the implementation of this system has been spread over the world for stationary and mobile power generation in residential, industrial and transportation uses. On the other hand, fuel cells as an emerging energy conversion device are potential prime movers for this cogeneration system due to its high heat production and flexibility in its fuel usage. Even though the fuel cell-based cogeneration system has been popularly implemented in research and commercialization sectors, the review regarding this technology is still limited. Focusing on the optimal design of the fuel cell-based cogeneration s... [more]
Techno-economic analysis of coke oven gas and blast furnace gas to methanol process with carbon dioxide capture and utilization
LINGYAN DENG DENG, Thomas Adams II
January 9, 2020 (v1)
Keywords: blast furnace gas, CO2 utilization and storage, COG desulphurization, Coke oven gas, Economic and sensitivity analysis, methanol production
This paper documents a process for converting coke oven gas (COG) and blast furnace gas (BFG) from steel refineries into methanol. Specifically, we propose the use of blast furnace gas (BFG) as an additional carbon source. The high CO2 and CO content of BFG make it a good carbon resource. In the proposed process, CO2 is recovered from the BFG and blended with H2O, H2, and CH4-rich COG to reform methane. Optimized amounts of H2O and CO2 are used to adjust the (H2 – CO2)/(CO + CO2) molar ratio in order to maximize the amount of methanol that is produced. In addition, the desulphurization process was modified to enable the removal of sulfur compounds, especially thiophene, from the COG. The process design and simulation results reported herein were then used to determine any potential environmental and economic benefits. This research is based on off-gas conditions provided by ArcelorMittal Dofasco, Hamilton, Ontario. In order to determine which conditions are most desirable for this retr... [more]
An Incubation System to Enhance Biogas and Methane Production: A Case Study of an Existing Biogas Plant in Umbria, Italy
Federica Liberti, Valentina Pistolesi, Mawaheb Mouftahi, Nejib Hidouri, Pietro Bartocci, Sara Massoli, Mauro Zampilli, Francesco Fantozzi
January 7, 2020 (v1)
Keywords: anaerobic digestion, biogas, CSTR, maize silage, olive pomace, pig slurry
The pre-incubation of digestate and recycling of microbes inside a continuously stirred tank reactor (CSTR) are effective ways to optimize the anaerobic digestion process and improve the performance of biogas and methane production, also in existing biogas plants. In this study, a digestate incubation system using a nutrient mix to boost the activity of microbes was coupled to a CSTR to boost biogas and methane production. This system has been tested both on a lab scale and on an industrial scale. On a pilot scale, the system achieved an increase of +16.47 v% in biogas production with respect to the conventional anaerobic digestion process, and an increase of +2 v% in methane content (from 65.94 v% to 67.84 v%). On an industrial scale, the use of this incubation reactor with a capacity of 1 m3 has led to an increase in methane yield of 12 v%. This system allows to maintain the syntrophic relationship between acid-producing bacteria and methanogens and contemporary push the development... [more]
A Process for the Recovery of Gallium from Gallium Arsenide Scrap
Tsai-Hsin Cheng, Chia-Ju Liu, Tang-Yi Tsai, Yun-Hwei Shen
January 7, 2020 (v1)
Keywords: Ga recovery, GaAs scrap, leaching-ion exchange
The recovery of gallium (Ga) from gallium arsenide (GaAs) scrap using a leaching-ion exchange method was investigated. The ground GaAs scrap was leached, using 2.0 N nitric acid at 30 °C for 1.0 h, and the dissolution of Ga and arsenic (As) reached 98%. The pregnant solution with a 1/20 dilution ratio was then passed through a weak acid chelating resin Diaion CR-11. Highly charged Ga3+ has the ability to form complexes with the chelating resin and separate from the coexisting H3AsO4 in the leachate with very low pH. The loaded column was eluted with 0.1 M H2SO4, and the final concentrated solution had 4.5 g/L of Ga with 99.3% purity. The effluent from the column was further processed to remove As by ferric arsenicate precipitation, and reused continuously as the dilution water for raw leachate.
Thermal Analysis of Vacuum Resistance Furnace
Saeed Badshah, Muhammad Atif, Ihsan Ul Haq, Suheel Abdullah Malik, Mujahid Badshah, Sakhi Jan
January 7, 2020 (v1)
Keywords: energy conservation, hot zone, numerical modeling, thermal insulation, vacuum resistance furnace
The current paper describes the effect of insulation thickness in a vacuum resistance furnace. An existing furnace was optimized for insulation thickness using analytical and numerical studies. Furnace heating efficiency was improved up to 64% by controlling the heat flow at the insulation face. The numerical results were validated experimentally and vice versa. The numerical results predicted a decrease in heat flow of 70%, while the experimentally achieved value was 64%. The percentage difference in numerical and experimental results was calculated to be 1.5−5% maximum in temperature value. The effect of mesh finesse was evaluated for thermal analysis and it was concluded that a very little difference of 5 °C occurs when element size is reduced 5 times. The study using numerical methods will help in designing better and upgraded furnaces with greater energy savings. Also, the application of numerical methods is proposed as an effective design and performance prediction tool during ma... [more]
Systematic Selection of Green Solvents and Process Optimization for the Hydroformylation of Long-Chain Olefines
Tobias Keßler, Christian Kunde, Steffen Linke, Kevin McBride, Kai Sundmacher, Achim Kienle
January 2, 2020 (v1)
Keywords: BARON, green solvents, hydroformylation, process optimization, TMS
Including ecologic and environmental aspects in chemical engineering requires new methods for process design and optimization. In this work, a hydroformylation process of long-chain olefines is investigated. A thermomorphic multiphase system is employed that is homogeneous at reaction conditions and biphasic at lower temperatures for catalyst recycling. In an attempt to replace the toxic polar solvent N,N-dimethylformamide (DMF), ecologically benign alternatives are selected using a screening approach. Economic process optimization is conducted for DMF and two candidate solvents. It is found that one of the green candidates performs similarly well as the standard benchmark solvent DMF, without being toxic. Therefore, the candidate has the potential to replace it.
Splitting Triglycerides with a Counter-Current Liquid−Liquid Spray Column: Modeling, Global Sensitivity Analysis, Parameter Estimation and Optimization
Mark Nicholas Jones, Hector Forero-Hernandez, Alexandr Zubov, Bent Sarup, Gürkan Sin
January 2, 2020 (v1)
Keywords: hydrolysis, Modelling, Optimization, parameter estimation, sensitivity analysis, spray column, vegetable oil
In this work we present the model of a counter-current spray column in which a triglyceride (tripalmitic triglyceride) is hydrolyzed by water and leads to fatty acid (palmitic acid) and glycerol. A finite volume model (FVM) of the column was developed to describe the reactive extraction process with a two-phase system and validated with an analytical model from the literature with the given data set encompassing six experimental runs. Global, variance-based (Sobol) sensitivity analysis allowed assessment of the sensitivity of the sweet water glycerol content in respect to liquid density, overall mass-transfer coefficient, reaction rate coefficient and the equilibrium ratio to rank them accordingly. Furthermore, parameter estimation with a differential evolution (DE) algorithm was performed to obtain among others the mass transfer, backmixing and reaction rate coefficients. The model was used to formulate and solve a process design problem regarding economic and sustainable performance.... [more]
Recovery of Protein from Dairy Milk Waste Product Using Alcohol-Salt Liquid Biphasic Flotation
Pei En Tham, Yan Jer Ng, Revathy Sankaran, Kuan Shiong Khoo, Kit Wayne Chew, Yee Jiun Yap, Masnindah Malahubban, Fitri Abdul Aziz Zakry, Pau Loke Show
January 2, 2020 (v1)
Keywords: dairy waste, liquid biphasic flotation, milk, protein, recovery
Expired dairy products are often disposed of due to the potential health hazard they pose to living organisms. Lack of methods to recover valuable components from them are also a reason for manufactures to dispose of the expired dairy products. Milk encompasses several different components with their own functional properties that can be applied in production of food and non-food technical products. This study aims to investigate the novel approach of using liquid biphasic flotation (LBF) method for protein extraction from expired milk products and obtaining the optimal operating conditions for protein extraction. The optimized conditions were found at 80% concentration ethanol as top phase, 150 g/L dipotassium hydrogen phosphate along with 10% (w/v) milk as bottom phase, and a flotation time of 7.5 min. The protein recovery yield and separation efficiency after optimization were 94.97% and 86.289%, respectively. The experiment has been scaled up by 40 times to ensure it can be commerc... [more]
Effect of Loading on Wheat Germ Drying in a Batch Fluidized Bed for Industrial Production
Der-Sheng Chan, Meng-I Kuo
January 2, 2020 (v1)
Keywords: dehydration, drying rate constant, fluidized bed drying, moisture content, wheat germ
A high loading production in the manufacturing process of wheat germ (WG) drying is important for reducing the production costs. From a cost perspective, the drying performance become more effective in a batch process when the loading increases. The objective of this investigation was to evaluate the drying performance of WG with different loadings, from 2 to 9 kg, at 120 °C in a fluidized bed dryer. The moisture content, according to the American Association of Cereal Chemists (AACC) method, and the water activity using a thermal hygrometer were measured. The absolute humidity, diffusivity of moisture, and thermal efficiency were analyzed using a mathematical model. An analysis of the dehydration flux demonstrated a linear relationship between dehydration time and WG loading using a fluidized bed dryer. The kinetics of WG drying were observed with a simple exponential model used to match the experimental observation, indicating that the drying rate constant decreases with an increase... [more]
Optimization of Baicalin, Wogonoside, and Chlorogenic Acid Water Extraction Process from the Roots of Scutellariae Radix and Lonicerae japonicae Flos Using Response Surface Methodology (RSM)
Jichang Li, Rui Wang, Zunlai Sheng, Zhiyong Wu, Chunli Chen, Muhammad Ishfaq
December 16, 2019 (v1)
Keywords: baicalin, chlorogenic acid, extraction process, HPLC, wogonoside
In this study, a simultaneous water extraction process for baicalin, wogonoside, and chlorogenic acid has been optimized. The effect of extraction temperature, extraction time, and liquid−solid ratio was scrutinized by single factor experiments and further analyzed by Box−Behnken design (BBD) approach using response surface methodology (RSM). The extraction yield of investigated compounds was determined by high performance liquid chromatography (HPLC). Single-factor experiments and response surface analysis results revealed that the optimized conditions are: Liquid to solid ratio 25:1 (mL/g), extraction temperature 93 °C, extraction time 2.4 h, and the extraction cycle two. Importantly, it has been noted that under the above conditions, concentrations of baicalin, wogonoside, and chlorogenic were 0.078, 0.031, and 0.013 mg/mL, respectively, and the overall desirability (OD) value was 0.76 which was higher than the non-optimized conditions and the deviation from the predicted OD value w... [more]
Valorization of Industrial Vegetable Waste Using Dilute HCl Pretreatment
Donald Blue, Dhan Lord Fortela, William Holmes, David LaCour, Shayla LeBoeuf, Cody Stelly, Ramalingam Subramaniam, Rafael Hernandez, Mark E. Zappi, Emmanuel D. Revellame
December 16, 2019 (v1)
Keywords: furans, lignocellulosic biomass, microbial inhibitors, onion wastes, organic acids
A solid vegetable waste stream was subjected to dilute acid (HCl) pretreatment with the goal of converting the waste into a form that is amenable to biochemical processes which could include microbial lipids, biohydrogen, and volatile organic acids production. Specifically, this study was conducted to identify the most suitable pretreatment condition that maximizes the yield or concentration of sugars while minimizing the production of compounds which are inhibitory to microbes (i.e., furfural, hydroxymethylfurfural, and organic acids). Temperatures from 50−150 °C and HCl loading from 0−7 wt % were studied to using an orthogonal central composite response surface design with eight center points. The effects of the variables under study on the resulting concentrations of sugars, organic acids, and furans were determined using the quadratic response surface model. Results indicated that the biomass used in this study contains about 5.7 wt % cellulose and 83.8 wt % hemicellulose/pectin. W... [more]
Techno-Economic Implications of Fed-Batch Enzymatic Hydrolysis
Ellen Argo, Deepak R. Keshwani
December 16, 2019 (v1)
Keywords: cellulosic ethanol, fed-batch hydrolysis, process simulation, Technoeconomic Analysis
Fed-batch enzymatic hydrolysis has the potential to improve the overall process of converting cellulosic biomass into ethanol. This paper utilizes a process simulation approach to identify and quantify techno-economic differences between batch and fed-batch enzymatic hydrolysis in cellulosic ethanol production. The entire process of converting corn stover into ethanol was simulated using SuperPro Designer simulation software. The analysis was conducted for a plant capacity of 2000 metric tons of dry biomass per day. A literature review was used to identify baseline parameters for the process. The sensitivity of the ethanol production cost to changes in sugar conversion efficiency, plant capacity, biomass cost, power cost, labor cost, and enzyme cost was evaluated using the process simulation. For the base scenario, the ethanol unit production cost was approximately $0.10/gallon lower for fed-batch hydrolysis. The greatest differences were seen in facilities costs, labor costs, and capi... [more]
Effects of Processing Conditions on the Simultaneous Extraction and Distribution of Oil and Protein from Almond Flour
Neiva M. de Almeida, Fernanda F. G. Dias, Maria I. Rodrigues, Juliana M. L. N. de Moura Bell
December 16, 2019 (v1)
Keywords: almond flour, enzyme-assisted aqueous extraction process, oil extraction, protein extraction, solubility
The enzyme-assisted aqueous extraction process (EAEP) is an environmentally friendly strategy that simultaneously extracts oil and protein from several food matrices. The aim of this study was to investigate the effects of pH (6.5−9.5), temperature (45−55 °C), solids-to-liquid ratio (SLR) (1:12−1:8), and amount of enzyme (0.5−1.0%) on the extraction and separation of oil and protein from almond flour using a fractional factorial design. Oil and protein extraction yields from 61 to 75% and 64 to 79% were achieved, respectively. Experimental conditions resulting in higher extractability were subsequently replicated for validation of the observed effects. Oil and protein extraction yields of 75 and 72% were achieved under optimized extraction conditions (pH 9.0, 50 °C, 1:10 SLR, 0.5% (w/w) of enzyme, 60 min). Although the use of enzyme during the extraction did not lead to significant increase in extraction yields, it did impact the extracted protein functionality. The use of enzyme and a... [more]
Energy Saving and Low-Cost-Oriented Design Processes of Blank’s Dimensions Based on Multi-Objective Optimization Model
Yongmao Xiao, Qingshan Gong, Xiaowu Chen
December 16, 2019 (v1)
Keywords: blank dimension design, energy saving, low cost, processing parameters
The blank’s dimensions are an important focus of blank design as they largely determine the energy consumption and cost of manufacturing and further processing the blank. To achieve energy saving and low cost during the optimization of blank dimensions design, we established energy consumption and cost objectives in the manufacturing and further processing of blanks by optimizing the parameters. As objectives, we selected the blank’s production and further processing parameters as optimization variables to minimize energy consumption and cost, then set up a multi-objective optimization model. The optimal blank dimension was back calculated using the parameters of the minimum processing energy consumption and minimum cost state, and the model was optimized using the non-dominated genetic algorithm-II (NSGA-II). The effect of designing blank dimension in saving energy and costs is obvious compared with the existing methods.
Optimization of Enzyme-Assisted Extraction of Flavonoids from Corn Husks
Antonio Zuorro, Roberto Lavecchia, Ángel Darío González-Delgado, Janet Bibiana García-Martinez, Pasqua L’Abbate
December 16, 2019 (v1)
Keywords: cellulase, corn husks, enzyme-assisted extraction, flavonoids, waste valorization
Corn husks are an important byproduct of the corn processing industry. Although they are a rich source of bioactive compounds, especially flavonoids, corn husks are usually disposed of or used as animal feed. In this paper, we investigate their recovery by an enzyme-assisted extraction process consisting of a pretreatment of the plant material with cellulase followed by solvent extraction with aqueous ethanol. A four-factor, three-level Box−Behnken design combined with the response surface methodology was used to optimize the enzyme dosage (0.3−0.5 g/100 g), incubation time (1.5−2.5 h), liquid-to-solid ratio (30−40 mL g−1) and ethanol concentration in the solvent (60−80% v/v). Under the optimal conditions, about 1.3 g of total flavonoids per 100 g of dry waste were recovered. A statistical analysis of the results was performed to provide a quantitative estimation of the influence of the four factors, alone or in combination, on the extraction yields. Overall, the results from this stud... [more]
Oil Recovery from Palm Kernel Meal Using Subcritical Water Extraction in a Stirred Tank Reactor
Johnnys Bustillo Maury, Andrés Aldana Rico, Cindy García Pinto, Ingrid Hernández Medina, Juan Urueta Urueta, Jerry W. King, Antonio Bula Silvera
December 16, 2019 (v1)
Keywords: clean separation, oil recovery, palm kernel meal, subcritical water extraction
Palm kernel meal (PKM) is one of the main byproducts of the oil palm industry. PKM can be obtained as the result of solvent or mechanical extraction of palm kernel oil; in both cases, meal has a remaining oil content that could be recovered. In this work, PKM coming from a mechanical pressing extraction system with an initial oil content between 7 to 8% (wt.) was treated with subcritical water in a batch stirred reactor. To find the proper operational conditions, a three-step experimental process was performed. Extraction temperature, reaction time, particle size and alkaline catalyst usage were selected as process factors. After subcritical extraction, the system was cooled down and depressurized; then oil phase was separated by centrifugation. After extraction, meal was oven-dried at 80 °C. A maximum recovery of 0.034 kg-oil/kg-meal was obtained at 423 K, 720 s and particles smaller than 0.001 m. The experimental procedure showed consistent extraction yields of 40% without modifying... [more]
Experimental Investigation of Sludge Treatment Using a Rotor-Stator Type Hydrodynamic Cavitation Reactor and an Ultrasonic Bath
Hyunsoo Kim, Xun Sun, Bonchan Koo, Joon Yong Yoon
December 13, 2019 (v1)
Keywords: performance comparison, rotor-stator type hydrodynamic cavitation reactor, sludge treatment, ultrasonication
In the present work, the sludge treatment performance of a sludge treatment using a rotor-stator type hydrodynamic cavitation reactor (HCR) was investigated. To verify the performance, a comparison with an ultrasonic bath was conducted in four experimental cases using three assessment factors. The HCR consisted of a rotor and three covers with inserted dimples resulting in variation of the cross-sectional area in a flow. The experimental cases were established using the same energy consumption for each device. Disintegration performance was analyzed with assessment factors using particle size distribution and sludge volume index (SVI), oxidation performance using total chemical oxygen demand (TCOD) and volatile suspended solids (VSS) reduction rate, as well as solubilization rate using soluble chemical oxygen demand (SCOD). As a result, the particle disintegration and oxidation performance of the HCR were generally superior to those of the ultrasonic bath. However, due to the contradic... [more]
Model Validation and Process Design of Continuous Single Pass Tangential Flow Filtration Focusing on Continuous Bioprocessing for High Protein Concentrations
Maximilian Johannes Huter, Christoph Jensch, Jochen Strube
December 11, 2019 (v1)
Keywords: Conceptual Process Design (CPD), Continuous Bioprocessing (CBP), membrane process, Modelling, Quality by Design (QbD), Single-Pass Tangential Flow Filtration (SPTFF), ultrafiltration
In this study, the continuous Single-Pass Tangential Flow Filtration (SPTFF) concept is adapted for high protein concentrations. The work is based on the previously validated physico-chemical model for low concentrations and high viscosities. The model contains the Stagnant Film Model for concentration polarization, as well as the Boundary Layer Model for the mass transfer through the membrane. The pressure drop is calculated as a function of the Reynolds number. By performing preliminary experiments with a single ultrafiltration (UF) cassette, the model parameter are determined. The presented model is validated for a multi-step Single-Pass Tangential Flow Filtration. With subsequent simulation studies, an optimized process is found and confirmed by experiments. The outcome of this work shows the potential to optimize this multi-parameter dependent unit operation. This is reached by a model-based optimization allowing significant reduction of experimental efforts and applying the Quali... [more]
An Investigation of the Techno-Economic and Environmental Aspects of Process Heat Source Change in a Refinery
Miroslav Variny, Dominika Jediná, Ján Kizek, Peter Illés, Ladislav Lukáč, Ján Janošovský, Marián Lesný
December 11, 2019 (v1)
Keywords: aromatics fractionation, cogeneration, external pollutant emissions, fuel, gas, heat conservation, process heat, refinery, thermal efficiency
This study of process heat source change in industrial conditions has been developed to aid engineers and energy managers with working towards sustainable production. It allows for an objective assessment from energetic, environmental, and economic points of view, thereby filling the gap in the systematic approach to this problem. This novel site-wide approach substantially broadens the traditional approach, which is based mostly on “cheaper” and “cleaner” process heat sources’ application and only takes into account local changes, while neglecting the synergic effect on the whole facility’s operations. The mathematical model employed assesses the performance change of all the affected refinery parts. The four proposed aromatic splitting process layouts, serving as a case study, indicate feasible heat and condensate conservation possibilities. Although the estimated investment needed for the most viable layout is over €4.5 million, its implementation could generate benefits of €0.5−1.5... [more]
Optimal Design of Permanent Magnet Arrangement in Synchronous Motors
Xiaoyu Liu, Qifang Lin, Weinong Fu
December 10, 2019 (v1)
Keywords: finite element method, Optimization, parallel, permanent magnet, synchronous motor
A general pattern, which can include different types of permanent magnet (PM) arrangement in PM synchronous motors (PMSMs) is presented. By varying the geometric parameters of the general pattern, the template can automatically produce different types of PM arrangement in the rotor. By choosing the best arrangement of PMs using optimization method, one can obtain a better performance and lower manufacturing cost. Six of the most widely used conventional types of rotor structures can be obtained through the parameter variation of the general pattern. These types include five embedded PM types and a traditional surface-mounted PM type. The proposed approach combines optimization method embedded with finite element method (FEM) for solving the multi-objective optimization for the PM structures. To save computing load, this paper employs a strategy of sub-group optimization, which is on account of the impact levels of the design parameters on the objective functions, and a parallel computa... [more]
A Simulation-Based Multi-Objective Optimization Design Method for Pump-Driven Electro-Hydrostatic Actuators
Longxian Xue, Shuai Wu, Yuanzhi Xu, Dongli Ma
December 10, 2019 (v1)
Keywords: dynamic stiffness, electro-hydrostatic actuator, energy consumption, multi-objective optimization, rise time, weight
A pump-driven actuator, which usually called an electro-hydrostatic actuator (EHA), is widely used in aerospace and industrial applications. It is interesting to optimize both its static and dynamic performances, such as weight, energy consumption, rise time, and dynamic stiffness, in the design phase. It is difficult to decide the parameters, due to the high number of objectives to be taken into consideration simultaneously. This paper proposes a simulation-based multi-objective optimization (MOO) design method for EHA with AMESim and a python script The model of an EHA driving a flight control surface is carried out by AMESim. The python script generates design parameters by using an intelligent search method and transfers them to the AMESim model. Then, the script can run a simulation of the AMESim model with a pre-set motion and load scenario of the control surface. The python script can also obtain the results when the simulation is finished, which can then be used to evaluate per... [more]
Effect of Gas Recycling on the Performance of a Moving Bed Temperature-Swing (MBTSA) Process for CO₂ Capture in a Coal Fired Power Plant Context
Giorgia Mondino, Carlos A. Grande, Richard Blom
December 10, 2019 (v1)
Keywords: adsorbents, Carbon Dioxide Capture, gas recycling, gProms, moving bed, post-combustion, process modelling, temperature-swing
A mathematical model of a continuous moving-bed temperature-swing adsorption (MBTSA) process for post-combustion CO₂ capture in a coal-fired power plant context has been developed. Process simulations have been done using single component isotherms and measured gas diffusion parameters of an activated carbon adsorbent. While a simple process configuration with no gas re-circulation gives quite low capture rate and CO₂ purity, 86% and 65%, respectively, more advanced process configurations where some of the captured gas is recirculated to the incoming flue gas drastically increase both the capture rate and CO₂ purity, the best configuration reaching capture rate of 86% and CO₂ purity of 98%. Further improvements can be achieved by using adsorbents with higher CO₂/N₂ selectivity and/or higher temperature of the regeneration section.
Design Methodology of a Power Split Type Plug-In Hybrid Electric Vehicle Considering Drivetrain Losses
Hanho Son, Kyusik Park, Sungho Hwang, Hyunsoo Kim
December 10, 2019 (v1)
Keywords: design methodology, drivetrain losses, dynamic programming, plug-in hybrid electric vehicle (PHEV), power split type
This paper proposes a design methodology for a power split type plug-in hybrid electric vehicle (PHEV) by considering drivetrain losses. Selecting the input split type PHEV with a single planetary gear as the reference topology, the locations of the engine, motor and generators (MGs), on the speed lever were determined by using the mechanical point considering the system efficiency. Based on the reference topology, feasible candidates were selected by considering the operation conditions of the engine, MG1, and a redundant element. To evaluate the fuel economy of the selected candidates, the loss models of the power electronic system and drivetrain components were obtained from the mathematical governing equation and the experimental results. Based on the component loss model, a comparative analysis was performed using a dynamic programming approach under the presence or absence of the drivetrain losses. It was found that the selection of the operating mode and the operation time of ea... [more]
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