Records with Subject: Process Design
Showing records 1 to 25 of 2079. [First] Page: 1 2 3 4 5 Last
Comprehensive Review of Safety Studies in Process Industrial Systems: Concepts, Progress, and Main Research Topics
Jialu Zhang, Haojie Ren, Hao Ren, Yi Chai, Zhaodong Liu, Xiaojun Liang
September 21, 2023 (v1)
Keywords: process industrial systems, research review, research topics, safety, safety assessment
This paper focuses on reviewing past progress in the advancement of definitions, methods, and models for safety analysis and assessment of process industrial systems and highlighting the main research topics. Based on the analysis of the knowledge with respect to process safety, the review covers the fact that the entire system does not have the ability to produce casualties, health deterioration, and other accidents, which ultimately cause human life threats and health damage. And, according to the comparison between safety and reliability, when a system is in an unreliable state, it must be in an unsafe state. Related works show that the main organizations and regulations are developed and grouped together, and these are also outlined in the literature. The progress and current research topics of the methods and models have been summarized and discussed in the analysis and assessment of safety for process industrial systems, which mainly illustrate that the dynamic operational safety... [more]
Effect of Self-Recirculating Casing Treatment on the Aerodynamic Performance of Ultra-High-Pressure-Ratio Centrifugal Compressors
Tengbo Fan, Baotong Wang, Chuanxiang Yan, Wenchao Zhang, Zhaoyun Song, Xinqian Zheng
September 21, 2023 (v1)
Keywords: aerodynamic stability, centrifugal compressor, multi-splitter blade, parametric model, self-recirculating casing treatment, ultra-high pressure ratio
The motivation to design a more efficient and compact aircraft engine leads to a continuous increase in overall pressure ratio and decrease in the stage number in compressors. Compared to the traditional multi-stage compressor, a single-stage ultra-high-pressure-ratio centrifugal compressor with a pressure ratio higher than 10.0 can significantly improve the engine’s power-to-weight ratio and fuel economy with a reduced structure complexity. Thus, it has great potential to be adopted in the compression system of advanced aero engines, such as turboshaft engines, in the future. However, the highly narrow Stable Flow Range (SFR) of ultra-high-pressure-ratio centrifugal compressors is a severe restriction for engineering applications. This research focuses on the aerodynamic performance of a ultra-high-pressure-ratio centrifugal compressor, and three-dimensional simulation is employed to investigate the effect of Self-Recirculating Casing Treatment (SRCT) on the performance and stability... [more]
Intelligent Optimization Design of Distillation Columns Using Surrogate Models Based on GA-BP
Lixiao Ye, Nan Zhang, Guanghui Li, Dungang Gu, Jiaqi Lu, Yuhang Lou
September 21, 2023 (v1)
Keywords: BP neural network, distillation column, Genetic Algorithm, intelligent design, life cycle assessment, surrogate modeling
The design of distillation columns significantly impacts the economy, energy consumption, and environment of chemical processes. However, optimizing the design of distillation columns is a very challenging problem. In order to develop an intelligent technique to obtain the best design solution, improve design efficiency, and minimize reliance on experience in the design process, a design methodology based on the GA-BP model is proposed in this paper. Firstly, a distillation column surrogate model is established using the back propagation neural network technique based on the training data from the rigorous simulation, which covers all possible changes in feed conditions, operating conditions, and design parameters. The essence of this step is to turn the distillation design process from model-driven to data-driven. Secondly, the model takes the minimum TAC as the objective function and performs the optimization search using a Genetic Algorithm to obtain the design solution with the min... [more]
Model-Based Optimization of Multi-Stage Nanofiltration Using the Solution-Diffusion−Electromigration Model
Tobias Hubach, Stefan Schlüter, Christoph Held
September 21, 2023 (v1)
Keywords: ion permeances, lithium, magnesium, membrane separation, Modelling, Optimization, process design, solution-diffusion–electromigration
Nanofiltration is well suited to separate monovalent ions from multivalent ions, such as the separation of Li+ and Mg2+ from seawater, a potential lithium source for the production of lithium-ion batteries. To the best of our knowledge, there is no existing work on the optimization of a multi-stage membrane plant that differentiates between different ions and that is based on a validated transport model. This study presents a method for modeling predefined membrane interconnections using discretization along the membrane length and across the membrane thickness. The solution-diffusion−electromigration model was used as the transport model in a fundamental membrane flowsheet, and the model was employed to optimize a given flowsheet with a flexible objective function. The methodology was evaluated for three distinct separation tasks, and optimized operating points were found. These show that permeances and feed concentrations might cause negative rejections and positive rejections (espec... [more]
Techno-Economic Considerations on Nanocellulose’s Future Progress: A Short Review
Giannis Penloglou, Aikaterini Basna, Alexandros Pavlou, Costas Kiparissides
September 20, 2023 (v1)
Keywords: bacterial nanocellulose (BNC), lignocellulosic biomass, nanocellulose, nanocrystalline cellulose (NCC), nanofibrillated cellulose (NFC), production cost, Technoeconomic Analysis
Nanocellulose (NC) is an emerging natural material that offers great potential for various applications due to its unique properties and renewable character. Nowadays, as NC production technologies are advancing, it is essential to evaluate their economic feasibility, technological maturity and commercialization potential using systematic techno-economic analysis (TEA). The present study considers both technical and economic aspects of NC production and analyzes them in two ways: first, by developing a new concept based on the production of different types of NC through the conversion of lignocellulosic biomass by chemical and mechanical technologies, and second, by a comparative review of existing TEA studies in the open literature. Three specific scenarios and two case studies are evaluated by comparing specific key performance indicators (KPIs), such as the production cost (PC) and minimum product selling price (MPSP) of NC. As a result, a short though comprehensive overview of the... [more]
Three-Dimensional Analysis of the Flow Characteristics Induced by a Cubic Artificial Reef with Diversions
Haiying Mao, Ziyi Wang, Cong Hu, Kairui Wang
September 20, 2023 (v1)
Keywords: cubic artificial reef with diversion, cut-opening ratio, flow characteristics, flow velocity, three-dimensional analysis
In this paper, the flow characteristics induced by a cubic artificial reef with diversions (DCAR) were investigated using computational fluid dynamics (CFD). The results showed that the design of a DCAR can greatly improve the flow field range compared to typical cubic artificial reefs. The upwelling volume of the DCAR was more than 16 times that of a typical cubic artificial reef. The flow field effect produced the best results when the cut-opening ratio (COR) was 0.1−0.2 with constant flow. The parameters of the upwelling and back vortex increased with an increase in the flow velocity, and it decreased with an increase in the COR. The drag coefficient was less affected by the flow velocity, which remained between 1.32 and 1.44. The new type of artificial reef can improve the flow characteristics around the reefs.
Harnessing Digestate Potential: Impact of Biochar and Reagent Addition on Biomethane Production in Anaerobic Digestion Systems
Alaa Salma, Nur Maisarah Binti Faeruz, Lydia Fryda, Hayet Djelal
September 20, 2023 (v1)
Keywords: anaerobic digestion, biochar, biomethane production, cattle manure digestate, cosubstrates
This article reports on an experiment that aimed to investigate the effects of digestate and cosubstrate input with varying biochar concentrations on methane production in anaerobic digestion processes. The findings revealed distinct trends in methane production among the substrates. Further investigations were conducted to evaluate the effects of different types of biochars on biomethane production from raw cattle manure digestate. Four conditions were tested: one raw digestate condition and three digestate conditions containing 1% of a different biochar type to one another. BC1 (PEFC-certified spruce BC) and BC2 (oak wood BC) showed promising results in enhancing biomethane production. About 884.23 NmL of methane was produced, with a yield and productivity of 22.80 NmL.g−1 and 1.62 NmL.g−−1 with BC1. However, BC3 (cow and chicken manure digestate BC) demonstrated lower biomethane production compared to raw digestate. Additionally, the study explored the effects of adding reagent... [more]
Optimising Spread-Layer Quality in Powder Additive Manufacturing: Assessing Packing Fraction and Segregation Tendency
Hamid Salehi, John Cummins, Enrico Gallino, Vivek Garg, Tong Deng, Ali Hassanpour, Mike Bradley
September 20, 2023 (v1)
Keywords: additive manufacturing, packing fraction, powder spreading, size and shape segregation
Powder bed fusion (PBF), a subset of additive manufacturing methods, is well known for its promise in the production of fully functional artefacts with high densities. The quality of the powder bed, commonly referred to as powder spreading, is a crucial determinant of the final quality of the produced artefact in the PBF process. Therefore, it is critical that we examine the factors that impact the powder spreading, notably the powder bed quality. This study utilised a newly developed testing apparatus, designed specifically for examining the quality of powder beds. The objective was to analyse the influence of various factors, including the recoater shape, recoater gap size, and the different powder flow properties, on the powder bed relative packing fraction. Additionally, the study aimed to assess the variation in the particle size and shape across the build plate. The results indicated that all of the variables examined had an impact on the relative packing fraction, as well as the... [more]
Performance Analysis of Organic Rankine Cycle with Internal Heat Regeneration: Comparative Study of Binary Mixtures and Pure Constituents in Warm Regions
Muhammad Ehtisham Siddiqui, Eydhah Almatrafi, Usman Saeed
September 20, 2023 (v1)
Keywords: binary mixtures, exergy performance, heat transfer, organic Rankine cycle, specific net power output, warm regions
There are various organic compounds that can be utilized in the organic Rankine cycle as working fluids. The selection of a suitable working fluid is complicated due to the large number of options and factors affecting the choice, such as thermodynamic properties, environmental impact, cost, etc. This study evaluates seven different pure organic compounds and twenty-one of their binary zeotropic mixtures as potential working fluids for the organic Rankine cycle powered by a heat source at 200 °C. The pure organic fluids show higher exergy efficiency, higher specific net power output, and lower heat exchange area requirements compared to the binary mixtures. Among the pure fluids, RE347mcc performs the best in terms of exergy efficiency, followed by neopentane, isopentane, and pentane. Cyclopentane exhibits the highest power production capacity per unit mass flow rate of the working fluid. Two mixtures, pentane/Novec 649 and cyclopentane/Novec 649, showed significantly higher exergy eff... [more]
Desiccant Technologies for Improving Air Quality: An Overview of the Brazilian Scenario and Comparison of Available Design Software for Manufactured Desiccant Wheels
York Castillo Santiago, Bruno Gomes Nunes, Geovani Souza Fontana, Daiane Busanello, Alexandre Fernandes Santos, Samuel Moreira Duarte Santos, Estefania Neiva de Mello, Leandro A. Sphaier
August 3, 2023 (v1)
Keywords: air conditioning systems, air quality, dehumidification, desiccant wheels
A review of desiccant dehumidification technologies for improving air quality is presented, mainly focusing on alternatives for air conditioning systems for minimizing Sick Building Syndrome. The principles and types of desiccant wheels, as well as the existing selection software for these types of equipment, were reviewed and comparatively evaluated. The study focused on the Brazilian context; thus, information about this country’s air conditioning systems and laws were evaluated. Possible applications of desiccant wheels, such as their integration into cooling cycles and the sensible heat wheel, were also analyzed. Finally, several examples of commercial desiccant wheel selection software that are useful in many situations were evaluated. Nevertheless, it was evidenced that the available software could not perform an operation analysis for only a specific period. Therefore, creating computational tools to select desiccant wheels is essential when considering the data from the differe... [more]
Evaluating the Efficiency of the Process Safety Management System through Analysis of Major Industrial Accidents in South Korea
Byung-Tae Yoo, Woo Sub Shim
August 3, 2023 (v1)
Keywords: major industrial accidents, process safety management (PSM), process safety report, safety operation plan
The process safety management (PSM) system was introduced in South Korea in 1996, wherein a company voluntarily organizes and manages a chemical accident prevention system, which contributes to reducing chemical accidents. However, large- and small-scale chemical accidents occur frequently. This trend necessitates analysis and improvement of the PSM systems. This study aimed to analyze the correlation between major industrial accidents, their main causes, the status of accidents by company size and industry, and the PSM evaluation grade through an analysis of 130 accidents that occurred in the past 17 years (2005−2021). The results showed that small- and medium-sized enterprises (SMEs) with fewer than 100 employees accounted for 36% of all accidents, indicating a higher occurrence rate than large companies. Additionally, the proportion of companies with inadequate PSM levels, rated as M-grade (M+, and M−), were 67.0%, suggesting a high probability of major industrial accidents. The res... [more]
Reasonable Size Design and Influencing Factors Analysis of the Coal Pillar Dam of an Underground Reservoir in Daliuta Mine
Zihan Chen, Xidong Zhao, Zhou Han, Yue Ji, Zhongjin Qiao
August 3, 2023 (v1)
Keywords: coal pillar dam, coal pillar width, mine water, underground reservoir
Underground reservoir water storage technology has become one important way to achieve efficient coal mining and water resource protection in the western mining areas of China, and the width of coal pillar dams is an important factor affecting the safe operation of underground reservoirs. In order to study the limitations on the reasonable size of a coal pillar dam, Daliuta Mine was selected as the engineering background and a theoretical formula for the reasonable width of a coal pillar dam was proposed. By combining theoretical analysis with numerical simulation analysis, the main influencing factors of the coal pillar dam were compared and analyzed. The research results indicated that changes in the mining height and coal parameters can cause a sharp change in the width of the plastic zone of the dam body. Then, mine water will have an impact on the width of the plastic zone and the width of the elastic core. Moreover, when the width of the coal pillar is smaller than the theoretica... [more]
Design of Polymeric Membranes for Air Separation by Combining Machine Learning Tools with Computer Aided Molecular Design
Jie-Ying Cheun, Joshua-Yeh-Loong Liew, Qian-Ying Tan, Jia-Wen Chong, Jecksin Ooi, Nishanth G. Chemmangattuvalappil
August 3, 2023 (v1)
Keywords: air separation, computer-aided molecular design, polymer membrane, rough set-based machine learning, topological indices
The growing importance of the membrane-based air separation processes results in an increasing demand for suitable polymeric membrane structures. This has spurred the interest in designing polymer structures for O2/N2 separation by employing a systematic approach. In this work, a computer-aided molecular design (CAMD)-based framework was developed to identify promising structures of polymers that can be used for air separation. To incorporate constraints in CAMD, the rough set-based machine learning (RSML) method was implemented to establish predictive models for the physical and transport properties of polymer owing to its interpretability. The deterministic rules generated from RSML would be interpreted scientifically reflecting the structure−property relationship to ensure that the molecules generated were feasible according to a scientific point of view. The most prominent rules selected were then integrated as constraints in CAMD. The relevant properties in this framework comprise... [more]
A Quantitative Examination of the Efficiency of a Biogas-Based Cooling System in Rural Regions
Kenan Saka
August 3, 2023 (v1)
Keywords: animal species, biogas-powered cooling system, energy and exergy analysis, methane content, triple-effect absorption cooling system
This study investigates the efficiency of a biogas-powered cooling system through the utilization of energy and exergy calculations. Biogas, which can be generated and stored in small-scale plants as needed, serves as a viable fuel source for absorption cooling systems. The present research focuses on the biogas consumption of a triple-effect absorption cooling system specifically designed to supply a fixed cooling load of 100 kW under varying operational conditions. This study highlights the coefficient of performance and exergetic coefficient of performance values of the system, along with the exergy destruction rates of its individual components, at the optimal temperatures of operation. Furthermore, to determine necessary biogas consumption, this study explores the establishment of dedicated farms for various animal species, ensuring an adequate number of animals for biogas production. The findings reveal a coefficient of performance of 1.78 and an exergetic coefficient of performa... [more]
Vibration Scale Model of a Converter Transformer Based on the Finite Element and Similarity Principle and Its Preparation
Hao Wang, Li Zhang, Youliang Sun, Liang Zou
August 3, 2023 (v1)
Keywords: converter transformer, finite element, prototype preparation, similarity model, vibration
A similarity criterion suitable for studying the vibration characteristics of converter transformers is proposed based on comprehensive consideration of geometric dimensions, electric field, magnetic field, force field, sound field, and coupling field interface interactions. By comparing the magnetic field, stress, displacement, sound field distribution, and vibration characteristics of the scale model of the converter transformer with the initial model, the reliability of the similarity criterion was determined. Based on the vibration similarity criterion of the converter transformer, a prototype of the proportional model was designed and manufactured, and vibration signals under no-load and load conditions were tested. These signals correspond to the vibration signals of the iron core and winding in the finite element model, respectively. Through comparative analysis, the reliability of the prototype and the vibration similarity model of the converter transformer has been proven, whi... [more]
Design and Analysis of Comprehensive Solar Utilization System Based on Photovoltaic Concentration and Spectral Splitting
Zhipeng He, Yizhi Tian
August 2, 2023 (v1)
Keywords: comprehensive utilization of solar energy, Fresnel lens concentration, GaAs cell, photoelectric conversion, photothermal conversion, spectral splitting, ZnO nanofluid
In order to address the issue of a solar utilization system with low efficiency, this paper designs a new solar conversion system based on photovoltaic concentration and spectral splitting. The system concentrates sunlight through a Fresnel lens and uses a hollow concave cavity to evenly distribute the incident energy flow. The spectral splitting medium separates the useful irradiance for the PV cell from those wavelengths that are more suited to heat generation. By considering the available wavelength of photovoltaic cells, the GaAs cell and a ZnO nanofluid were selected for this paper. It was found that installing the hollow concave cavity improved the spot uniformity of the PV cell surface by 17%. The output efficiency of the system under various circumstances was analyzed. The results show that at a concentration ratio of 50 and a light intensity of 1000 W/m2, photoelectric conversion efficiency increased by 0.81%. When compared to direct concentration, the photoelectric conversion... [more]
A Refractive Index- and Density-Matched Liquid−Liquid System Developed Using a Novel Design of Experiments
Jianxin Tang, Chenfeng Wang, Fei Liu, Xiaoxia Yang, Rijie Wang
August 2, 2023 (v1)
Keywords: design of experiments, Latin hypercube sampling, neutrally buoyant, optical diagnosis, refractive index and density matching
Refractive index and density matching are essential for optical measurements of neutrally buoyant liquid−liquid flows. In this study, we proposed a design of experiments (DoE) to develop refractive index and density matching systems, including objective setting, candidates screening, sampling and fitting, and a detailed matching process. Candidates screening criteria based on the density and refractive index ranges of the aqueous and organic phases were used. Using the DoE, we proposed a system with a ternary aqueous phase potassium thiocyanate (KSCN)/ammonium thiocyanate (NH4SCN) solution and m-dichlorobenzene/tripropionin solution as the organic phase to achieve the tuning of the RI and density simultaneously. Empirical correlations of the refractive index and density with respect to the concentration and temperature for the three mixtures were obtained by combining Latin hypercube sampling with binary polynomial fitting. Correlations were validated with existing data in the literatu... [more]
Selection of Ideal MSW Incineration and Utilization Technology Routes Using MCDA for Different Waste Utilization Scenarios and Variable Conditions
Zakariya Kaneesamkandi, Ateekh Ur-Rehman, Yusuf Siraj Usmani
August 2, 2023 (v1)
Keywords: desalination from waste, district cooling from waste, energy from waste, fluidized bed combustion, grate combustion, multi-criteria decision analysis, waste combustion
Liability to prevent the consequences of an unhealthy situation due to accumulating toxic and hazardous emissions caused by open dumping of municipal solid waste with increasing urbanization has necessitated a renewed thinking on waste disposal. Grate-fired incineration systems were adopted by urban management in the past and present, but with criticism due to the formation of airborne emissions. Improved combustion methods like fluidized beds are now propagated because of current requirements like efficient energy recovery potential, stricter emission norms, adaptability with urban growth, adaptability to co-firing with other waste like biomass, edible oil wastes or industrial effluent, and integration with conventional energy generation. Such a comprehensive and futuristic approach is more sustainable for the community. A multi-criteria decision-making tool is used to identify the best technology option between grate combustion and fluidized bed combustion for disposing and energy re... [more]
Influence of Central Air on Flow and Combustion Characteristics and Low-Load Stabilization Performance of a Babcock Burner
Chunchao Huang, Zhengqi Li, Yufei Wang, Yue Lu, Huacai Liu, Zhichao Chen
August 2, 2023 (v1)
Keywords: central air, flow characteristics, low-load stable combustion, swirl burner
On a cold single-phase test stand, the effect of central air on the exit flow field of Babcock, Germany, burner was investigated. Industrial measurements were taken for a 700 MW wall-fired pulverized-coal utility boiler with above burners. Gas temperature, gas composition and concentration in the burner area were measured at 444 MW, 522 MW and 645 MW loads, respectively. Only when the central air mass flow was zero did a center reflux zone exist in the burner outlet area. The steady combustion of faulty coal was aided by early mixing of primary and secondary air, which was made possible by the decreased central air mass flow. At all different loads, the pulverized coal in center region took a long distance to ignite. The temperature in center steadily dropped as central air mass flow decreased, while the temperature in secondary air region gradually rose. Within 1.5 m from the primary air duct outlet, the highest CO concentration was 25 ppm and the highest O2 concentration was close to... [more]
Cost-Effective Processes for Denim Production Wastewater: Dual Criterial Optimization of Techno-Economical Parameters by RSM and Minimization of Energy Consumption of Photo Assisted Fenton Processes via Direct Photovoltaic Solar Panel Integration
Murat Solak
August 2, 2023 (v1)
Keywords: denim production wastewater, dual criterial optimization, operating cost analysis, oxidation process, photovoltaic solar panel, response surface methodology
Denim production wastewater is an industrial wastewater with a high organic pollutant content. The aim of this study was to improve a cost-effective method via solar panel integration to the photo Fenton process (PFP) and photo electrochemical Fenton process (PEFP) for removing high chemical oxygen demand (COD) from denim production wastewater. To determine process parameter values, the double criterial optimization option was used. The results that maximized the COD removal efficiency and minimized the operating cost of two oxidation processes were determined by response surface methodology (RSM). Optimum operation conditions for the PFP process were 3.18 initial pH, 2.3 g/L Fe2+ concentration, and 27 g/L H2O2 concentration while they were 3.00 initial pH, 27.06 A/m2 current density, and 28.16 g/L H2O2 concentration for PEFP. At the optimum conditions, COD and the total organic carbon (TOC) removal efficiency of PFP were 85% and 61%, respectively. They were determined as 90% and 73% i... [more]
A New ODE-Based Julia Implementation of the Anaerobic Digestion Model No. 1 Greatly Outperforms Existing DAE-Based Java and Python Implementations
Courtney Allen, Alexandra Mazanko, Niloofar Abdehagh, Hermann J. Eberl
August 2, 2023 (v1)
Keywords: ADM1, anaerobic digestion, Java programming language, Julia programming language, Numerical Methods, performance comparison, Python programming language
The Anaerobic Digestion Model 1 is the quasi-industry standard for modelling anaerobic digestion, and it has seen several new implementations in recent years. It is assumed that these implementations would give the same results; however, a thorough comparison of these implementations has never been reported. This paper considers four different implementations of ADM1: one in Julia, one in Java, and two in Python. The Julia code is a de novo implementation of the ODE formulation of ADM1 that is reported here for the first time. The existing Java and Python codes implement the more common DAE formulation. Therefore, this paper also examines how DAE implementations compare to ODE implementations in terms of computational speed as well as solutions returned. As expected, the ODE and DAE forms both return comparable solutions. However, contrary to popular belief, the Julia ODE implementation is faster than the DAE implementations, namely by one to three orders of magnitude of compute time,... [more]
Design and Implementation of a Crowdsensing-Based Air Quality Monitoring Open and FAIR Data Infrastructure
Paolo Diviacco, Massimiliano Iurcev, Rodrigo José Carbajales, Alberto Viola, Nikolas Potleca
August 2, 2023 (v1)
Keywords: citizen science, crowdsensing, infrastructure, low-cost sensors, particulate matter
This work reports on the development of a real-time vehicle sensor network (VSN) system and infrastructure devised to monitor particulate matter (PM) in urban areas within a participatory paradigm. The approach is based on the use of multiple vehicles where sensors, acquisition and transmission devices are installed. PM values are measured and transmitted using standard mobile phone networks. Given the large number of acquisition platforms needed in crowdsensing, sensors need to be low-cost (LCS). This sets limitations in the precision and accuracy of measurements that can be mitigated using statistical methods on redundant data. Once data are received, they are automatically quality controlled, processed and mapped geographically to produce easy-to-understand visualizations that are made available in almost real time through a dedicated web portal. There, end users can access current and historic data and data products. The system has been operational since 2021 and has collected over... [more]
Industrial Chemistry Reactions: Kinetics, Mass Transfer and Industrial Reactor Design (II)
Elio Santacesaria, Riccardo Tesser, Vincenzo Russo
August 2, 2023 (v1)
Due to the success of the first edition of the Special Issue “Industrial Chemistry Reactions: Kinetics, Mass Transfer and Industrial Reactor Design” in terms of both the quantity and quality of the published papers, we thought it would be prudent to announce a second edition [...]
Numerical Investigations of Heat Transfer and Fluid Flow Characteristics in Microchannels with Bionic Fish-Shaped Ribs
Quanyue Gao, Haibo Zou, Juan Li
July 13, 2023 (v1)
Keywords: bionic ribs arrangement, heat transfer, microchannel, numerical simulation, thermal boundary layers
Microchannel cooling technology is an effective method to solve local thermal stacking. In this paper, four innovative microchannels with bionic fish-shaped rib arrangements (CM-O, CM-R, CM-H, and CM-G) are designed by imitating geese and fish clusters. The heat transfer and flow characteristics of the microchannels are simulated numerically at different Reynold’s numbers (Re = 200 − 1600). The liquid water temperature and flow field in the four innovative microchannels with bionic ribs are analyzed. The results show that the ribs’ arrangement has an influence on the thermal performance of microchannels. Compared to the smooth microchannel (CM), the of the Nu microchannels with the bionic fish-shaped ribs increases by 33.00−53.26% while the fave increases by 28.63−34.93% at Re = 1200. The vortices around the ribs are clearly observed which improves the temperature gradient. The performance evaluation criterion (PEC) of CM-H is higher than that of the others. This indicates that the rib... [more]
Development of a Continuous Process Chain for Selective Recovery and Purification of Rare Metals
Timo Dobler, Simon Buchheiser, Thomas Gaschler, Stefan Platzk, Harald Kruggel-Emden, Hermann Nirschl, Marco Gleiß
July 13, 2023 (v1)
Keywords: cake washing, filtration, process design, purification, recovery, solvent extraction
Solar cells, liquid crystal displays (LCDs) and light-emitting diodes (LEDs) have become more and more important in recent decades. Crucial components of such electronic devices include rare metals (e.g., indium and gallium), which are only available in limited quantities. In order to meet their rising demand in the coming years, recycling processes, especially those that enable selective recovery of the individual components, are steadily gaining in importance. One conceivable method is particle-loaded solvent extraction followed by mechanical processing. Therefore, we first investigated the possibility of recovering individual particle fractions from a multicomponent mixture on the basis of the surface properties. Both UV−Vis spectroscopy and small-angle X-ray scattering (WAXS) were used for evaluation. The conducted experiments showed, among other things, that the indium oxide content increased from 50% to 99% in a binary system and from 33% to 94% in a ternary compound. In addition... [more]
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