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Inventions
Volume 9
Issue 5
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Inventions, Volume 9, Issue 5 (October 2024) – 20 articles

Cover Story (view full-size image): To alleviate the adverse effects of shock boundary layer interaction, active and passive control strategies have been explored. This research investigates the behavior of passive perforated plates applied to NACA0012 airfoils in cascade configurations. Six cascade setups, including a “no control” configuration, were manufactured with orifice sizes from 0.5 to 1.2 mm. A high-speed wind tunnel, with Schlieren optics and wall static pressure sensors, was used to analyze shock wave pattern changes. 3D numerical simulations using Ansys FLUENT continuously revealed that the perforated plates altered the shock structure, weakening a strong normal shock into an X-type shock. A 1% total pressure loss occurred, balancing reduced shock losses with increased viscous losses. Further research on geometric optimization is needed to enhance outcomes. View this paper
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23 pages, 4313 KiB  
Article
Corrosion-Resistant Polymer Composite Tubes with Enhanced Thermal Conductivity for Heat Exchangers
by Jan-Hendrik Imholze and Heike Glade
Inventions 2024, 9(5), 111; https://doi.org/10.3390/inventions9050111 - 21 Oct 2024
Viewed by 1175
Abstract
The heat transfer surfaces of heat exchangers are usually made of metals which may suffer from severe corrosion. When corrosive fluids are present, highly corrosion-resistant metals, graphite or ceramics are used, resulting in high costs. This study presents measured data on the thermophysical [...] Read more.
The heat transfer surfaces of heat exchangers are usually made of metals which may suffer from severe corrosion. When corrosive fluids are present, highly corrosion-resistant metals, graphite or ceramics are used, resulting in high costs. This study presents measured data on the thermophysical and mechanical properties of recently developed corrosion-resistant polymer composite tubes for use in heat exchangers. Extruded polymer composite tubes based on polypropylene or polyphenylene sulfide filled with graphite flakes were investigated. The anisotropic thermal conductivities of the polymer composite tubes were measured at various temperatures. The through-wall thermal conductivity of the tubes made of polypropylene filled with 50 vol.% graphite is increased by a factor of 30 compared to pure polypropylene, resulting in a thermal conductivity of 6.5 W/(m K) at 25 °C. The tubes composed of polyphenylene sulfide filled with 50 vol.% graphite have a through-wall thermal conductivity of 4.5 W/(m K) at 25 °C. The mechanical properties of the polymer composites were measured using tensile and flexural tests at different temperatures. The composite materials are more rigid and keep their mechanical properties up to a higher temperature level compared to the unfilled polymers. Surface roughness measurements show the very smooth and sealed surface of the composite tubes. The results contribute to establishing the viability of using polymer composites for heat exchanger applications with corrosive fluids. Full article
(This article belongs to the Special Issue Innovations in Heat Exchangers)
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23 pages, 15644 KiB  
Article
Effects of Perforated Plates on Shock Structure Alteration for NACA0012 Cascade Configurations
by Mihnea Gall, Oana Dumitrescu, Valeriu Drăgan and Daniel-Eugeniu Crunțeanu
Inventions 2024, 9(5), 110; https://doi.org/10.3390/inventions9050110 - 6 Oct 2024
Viewed by 989
Abstract
To alleviate the shock boundary layer interaction adverse effects, various active or passive flow control strategies have been investigated in the literature. This research sheds light on the behavior of perforated plates as passive flow control techniques applied to NACA0012 airfoils in cascade [...] Read more.
To alleviate the shock boundary layer interaction adverse effects, various active or passive flow control strategies have been investigated in the literature. This research sheds light on the behavior of perforated plates as passive flow control techniques applied to NACA0012 airfoils in cascade configurations. Two identical perforated plates with shallow cavities underneath are accommodated on the upper and lower surfaces of each airfoil in the cascade arrangement. Six different cascade arrangements, including a baseline configuration with no control applied, are additively manufactured, with different perforated plate orifice sizes in the range of 0.5–1.2 mm. A high-speed wind tunnel with Schlieren optical diagnosis and wall static pressure taps is used to investigate the changes in the shock waves pattern triggered by the perforated plates. Steady 3D density-based numerical simulations in Ansys FLUENT are conducted for further analysis and validation. In the cascade configuration, the perforated plates alter the shock structure, and the strong normal shock wave is replaced by a weaker X-type shock structure. Eventually, a 1% penalty in overall total pressure loss is induced by the perforated plates because of the negative loss balance between the reduced shock losses and the enhanced viscous losses. Further studies on perforated plate geometrical features are needed to improve this outcome in a cascade arrangement. Full article
(This article belongs to the Section Inventions and Innovation in Energy and Thermal/Fluidic Science)
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20 pages, 666 KiB  
Article
Spring Runoff Simulation of Snow-Dominant Catchment in Steppe Regions: A Comparison Study of Lumped Conceptual Models
by Stanislav Eroshenko, Evgeniy Shmakov, Dmitry Klimenko and Irina Iumanova
Inventions 2024, 9(5), 109; https://doi.org/10.3390/inventions9050109 - 4 Oct 2024
Viewed by 961
Abstract
This paper explores the application of conceptual hydrological models in optimizing the operation of hydroelectric power plants (HPPs) in steppe regions, a crucial aspect of promoting low-carbon energy solutions. The study aims to identify the most suitable conceptual hydrological model for predicting reservoir [...] Read more.
This paper explores the application of conceptual hydrological models in optimizing the operation of hydroelectric power plants (HPPs) in steppe regions, a crucial aspect of promoting low-carbon energy solutions. The study aims to identify the most suitable conceptual hydrological model for predicting reservoir inflows from multiple catchments in a steppe region, where spring runoff dominates the annual water volume and requires careful consideration of snowfall. Two well-known conceptual models, HBV and GR6J-CemaNeige, which incorporate snow-melting processes, were evaluated. The research also investigated the best approach to preprocessing historical data to enhance model accuracy. Furthermore, the study emphasizes the importance of accurately defining low-water periods to ensure reliable HPP operation through more accurate inflow forecasting. A hypothesis was proposed to explore the relationship between atmospheric circulation and the definition of low-water periods; however, the findings did not support this hypothesis. Overall, the results suggest that combining the conceptual models under consideration can lead to more accurate forecasts, underscoring the need for integrated approaches in managing HPP reservoirs and promoting sustainable energy production. Full article
(This article belongs to the Special Issue Emerging Trends and Innovations in Renewable Energy)
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29 pages, 6072 KiB  
Article
Optimized Wavelet Transform for the Development of an Algorithm Designed for the Analysis of Digital Substation Electrical Equipment Parameters
by Alexander S. Efimov, Stanislav A. Eroshenko, Pavel V. Matrenin and Vladislav V. Popovtsev
Inventions 2024, 9(5), 108; https://doi.org/10.3390/inventions9050108 - 29 Sep 2024
Viewed by 887
Abstract
This study emphasizes the urgent need for systems that monitor the operational states of primary electrical equipment, particularly power transformers. The rapid digitalization of and increasing data volumes from substations, coupled with the inability to retrofit outdated equipment with modern sensors, underscore the [...] Read more.
This study emphasizes the urgent need for systems that monitor the operational states of primary electrical equipment, particularly power transformers. The rapid digitalization of and increasing data volumes from substations, coupled with the inability to retrofit outdated equipment with modern sensors, underscore the necessity for algorithms that analyze the operational parameters of digital substations based on key power system metrics such as current and voltage. This research focuses on digital substations with Architecture III and aims to develop an algorithm for processing digital substation data through an appropriate mathematical tool for time-series analysis. For this purpose, the fast discrete wavelet transform was chosen as the most suitable method. Within the framework of the research, possible transformer faults were divided into two categories by the nature of their manifestation. A mathematical model for two internal transformer fault categories was built. The most effective parameters from the point of view of the possibility of identifying an internal fault were selected. The proposed algorithm shows its effectiveness in the compact representation of the signal and compression of the time series of the parameter to be monitored. Full article
(This article belongs to the Special Issue Recent Advances and Challenges in Emerging Power Systems: 2nd Edition)
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24 pages, 5160 KiB  
Article
Operating Characteristics of a Wave-Driven Plasma Thruster for Cutting-Edge Low Earth Orbit Constellations
by Anna-Maria Theodora Andreescu, Daniel Eugeniu Crunteanu, Maximilian Vlad Teodorescu, Simona Nicoleta Danescu, Adrian Stoicescu, Alexandru Cancescu and Alexandru Paraschiv
Inventions 2024, 9(5), 107; https://doi.org/10.3390/inventions9050107 - 29 Sep 2024
Viewed by 844
Abstract
This paper outlines the development phases of a wave-driven Helicon Plasma Thruster for cutting-edge Low Earth Orbit (LEO) constellations. The two-stage ambipolar electric propulsion (EP) system combines the efficient ionization of an ultra-compact helicon reactor with plasma acceleration based on an ambipolar electric [...] Read more.
This paper outlines the development phases of a wave-driven Helicon Plasma Thruster for cutting-edge Low Earth Orbit (LEO) constellations. The two-stage ambipolar electric propulsion (EP) system combines the efficient ionization of an ultra-compact helicon reactor with plasma acceleration based on an ambipolar electric field provided by a magnetic nozzle. This paper reveals maturation challenges associated with an emerging EP system in the hundreds-watt class, followed by outlook strategies. A 3 cm diameter helicon reactor was operated using argon gas under a time-modulated RF power envelope ranging from 250 W to 500 W with a fixed magnetic field strength of 400 G. Magnetically enhanced inductively coupled plasma reactor characteristics based on half-wavelength right helical and Nagoya Type III antennas under capacitive (E-mode), inductive (W-mode), and wave coupling (W-mode) were systematically investigated based on Optical Emission Spectroscopy. The operation characteristics of a wave-heated reactor based on helicon configuration were investigated as a function of different operating parameters. This work demonstrates the ability of two-stage HPT using a compact helicon reactor and a cusped magnetic field to outperform today’s LEO spacecraft propulsion. Full article
(This article belongs to the Topic Innovation and Inventions in Aerospace and UAV Applications)
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22 pages, 3783 KiB  
Article
Energy Analysis of Standardized Shipping Containers for Housing
by Elena Arce Fariña, Mirela Panait, José María Lago-Cabo and Raquel Fernández-González
Inventions 2024, 9(5), 106; https://doi.org/10.3390/inventions9050106 - 27 Sep 2024
Viewed by 1169
Abstract
Shipping containers that remain in ports after exporting or importing products cause an environmental and logistical problem. Transporting them to the port of origin is costly; therefore, some of them are stored in the regions of destination. Recycling or reusing them in an [...] Read more.
Shipping containers that remain in ports after exporting or importing products cause an environmental and logistical problem. Transporting them to the port of origin is costly; therefore, some of them are stored in the regions of destination. Recycling or reusing them in an efficient and sustainable way represents a clean alternative. The purpose of this article is to analyze the feasibility and impact of implementing different insulating configurations on the energy demands required by a house based on a construction with standardized shipping containers. More specifically, it assesses the impact of the different orientations in which the dwelling can be arranged, depending on the location and its meteorological data. To this aim, a construction model will be developed in which first, the geometrical parameters are defined, and second, the energy characteristics are identified. The results show that, in Southwest Europe, the western orientation generates a saving of 10% of the energy demand compared to the less favourable orientation, which is the southern one. Full article
(This article belongs to the Special Issue Thermodynamic and Technical Analysis for Sustainability (Volume 3))
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18 pages, 6025 KiB  
Article
Innovative Design of a Continuous Ultrasound Bath for Effective Lignocellulosic Biomass Pretreatment Based on a Theorical Method
by Paula Andrea Ramirez Cabrera, Alejandra Sophia Lozano Pérez and Carlos Alberto Guerrero Fajardo
Inventions 2024, 9(5), 105; https://doi.org/10.3390/inventions9050105 - 26 Sep 2024
Cited by 1 | Viewed by 1056
Abstract
Ultrasonic pretreatment is a crucial step in the bioconversion of lignocellulosic biomass, such as peapods, into valuable products. Ultrasonic pretreatment is a highly effective physical method that utilizes ultrasonic waves to enhance various processes. Biomass pretreatment is achieved through physical effects such as [...] Read more.
Ultrasonic pretreatment is a crucial step in the bioconversion of lignocellulosic biomass, such as peapods, into valuable products. Ultrasonic pretreatment is a highly effective physical method that utilizes ultrasonic waves to enhance various processes. Biomass pretreatment is achieved through physical effects such as acoustic cavitation, which disrupts the biomass structure, and chemical effects like radical formation, which breaks down complex molecules. This article focuses on the characteristics, types, and applications of ultrasonic pretreatment in peapods, with a particular emphasis on its role in lignin removal and ultrasound design. An innovative mechanical design in a CAD application of a continuous ultrasound treatment with a capacity of 5 L and an FEA analysis of the equipment are presented as results, providing insights for the design and optimization of ultrasonic pretreatment processes. Full article
(This article belongs to the Section Inventions and Innovation in Design, Modeling and Computing Methods)
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24 pages, 14746 KiB  
Article
Hydraulic Design of an Ultracompact Liquid Methane–Liquid Oxygen Turbopump for a Mid-Scale Thruster for Upper Stage Application
by Alexandru-Claudiu Cancescu, Daniel-Eugeniu Crunteanu, Anna-Maria Theodora Andreescu, Simona-Nicoleta Danescu and Valeriu Dragan
Inventions 2024, 9(5), 104; https://doi.org/10.3390/inventions9050104 - 25 Sep 2024
Cited by 1 | Viewed by 1026
Abstract
As space missions proliferate and the payload requirements increase, the environmental impact of thrusters can no longer be considered negligible. Therefore, less impactful fuels such as methane are starting to be considered for launchers. In this paper we present a design case study [...] Read more.
As space missions proliferate and the payload requirements increase, the environmental impact of thrusters can no longer be considered negligible. Therefore, less impactful fuels such as methane are starting to be considered for launchers. In this paper we present a design case study for such a turbopump. Using both analytical models and Computational Fluid Dynamics techniques, we were able to reduce the size and weight of the turbopump assembly. Also, due to the elimination of some auxiliary systems, the overall efficiency was enhanced. This paper’s findings and methods can be transferred not only to launchers in its own class, but also to larger scale engines with a similar construction. Full article
(This article belongs to the Special Issue Thermodynamic and Technical Analysis for Sustainability (Volume 3))
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2 pages, 130 KiB  
Correction
Correction: Freddi et al. Reverse Engineering of a Racing Motorbike Connecting Rod. Inventions 2023, 8, 23
by Marco Freddi, Patrich Ferretti, Giulia Alessandri and Alfredo Liverani
Inventions 2024, 9(5), 103; https://doi.org/10.3390/inventions9050103 - 24 Sep 2024
Viewed by 532
Abstract
In the original publication [...] Full article
(This article belongs to the Collection Feature Innovation Papers)
25 pages, 3047 KiB  
Article
Hierarchical Dynamic Spatio-Temporal Graph Convolutional Networks with Self-Supervised Learning for Traffic Flow Forecasting
by Siwei Wei, Yanan Song, Donghua Liu, Sichen Shen, Rong Gao and Chunzhi Wang
Inventions 2024, 9(5), 102; https://doi.org/10.3390/inventions9050102 - 20 Sep 2024
Viewed by 1254
Abstract
It is crucial for both traffic management organisations and individual commuters to be able to forecast traffic flows accurately. Graph neural networks made great strides in this field owing to their exceptional capacity to capture spatial correlations. However, existing approaches predominantly focus on [...] Read more.
It is crucial for both traffic management organisations and individual commuters to be able to forecast traffic flows accurately. Graph neural networks made great strides in this field owing to their exceptional capacity to capture spatial correlations. However, existing approaches predominantly focus on local geographic correlations, ignoring cross-region interdependencies in a global context, which is insufficient to extract comprehensive semantic relationships, thereby limiting prediction accuracy. Additionally, most GCN-based models rely on pre-defined graphs and unchanging adjacency matrices to reflect the spatial relationships among node features, neglecting the dynamics of spatio-temporal features and leading to challenges in capturing the complexity and dynamic spatial dependencies in traffic data. To tackle these issues, this paper puts forward a fresh approach: a new self-supervised dynamic spatio-temporal graph convolutional network (SDSC) for traffic flow forecasting. The proposed SDSC model is a hierarchically structured graph–neural architecture that is intended to augment the representation of dynamic traffic patterns through a self-supervised learning paradigm. Specifically, a dynamic graph is created using a combination of temporal, spatial, and traffic data; then, a regional graph is constructed based on geographic correlation using clustering to capture cross-regional interdependencies. In the feature learning module, spatio-temporal correlations in traffic data are subjected to recursive extraction using dynamic graph convolution facilitated by Recurrent Neural Networks (RNNs). Furthermore, self-supervised learning is embedded within the network training process as an auxiliary task, with the objective of enhancing the prediction task by optimising the mutual information of the learned features across the two graph networks. The superior performance of the proposed SDSC model in comparison with SOTA approaches was confirmed by comprehensive experiments conducted on real road datasets, PeMSD4 and PeMSD8. These findings validate the efficacy of dynamic graph modelling and self-supervision tasks in improving the precision of traffic flow prediction. Full article
(This article belongs to the Special Issue Advanced Technologies and Artificial Intelligence for Sustainable and Intelligent Transportation Systems)
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22 pages, 1281 KiB  
Review
Review of Existing Tools for Software Implementation of Digital Twins in the Power Industry
by Irina F. Iumanova, Pavel V. Matrenin and Alexandra I. Khalyasmaa
Inventions 2024, 9(5), 101; https://doi.org/10.3390/inventions9050101 - 19 Sep 2024
Viewed by 1201
Abstract
Digital twin technology is an important tool for the digitalization of the power industry. A digital twin is a concept that allows for the creation of virtual copies of real objects that can be used for technical state analysis, predictive analysis, and optimization [...] Read more.
Digital twin technology is an important tool for the digitalization of the power industry. A digital twin is a concept that allows for the creation of virtual copies of real objects that can be used for technical state analysis, predictive analysis, and optimization of the operation of power systems and their components. Digital twins are used to address different issues, including the management of equipment reliability and efficiency, integration of renewable energy sources, and increased flexibility and adaptability of power grids. Digital twins can be developed with the use of specialized software solutions for designing, prototyping, developing, deploying, and supporting. The existing diversity of software requires systematization for a well-informed choice of digital twin’s development tool. It is necessary to take into account the technical characteristics of power systems and their elements (equipment of power plants, substations and power grids of power systems, mini- and microgrids). The reviews are dedicated to tools for creating digital twins in the power industry. The usage of Digital Twin Definition Language for the description data of electromagnetic, thermal, and hydrodynamic models of a power transformer is presented. Full article
(This article belongs to the Special Issue From Sensing Technology towards Digital Twin in Applications, 2nd Edition)
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3 pages, 146 KiB  
Editorial
Innovative Research and Applications in Hydrodynamics and Flow Control
by Peng Du, Haibao Hu and Xiaopeng Chen
Inventions 2024, 9(5), 99; https://doi.org/10.3390/inventions9050099 - 13 Sep 2024
Viewed by 665
Abstract
This work aims to collect cutting-edge developments in the area of hydrodynamics and flow control, including both fundamental and engineering research [...] Full article
(This article belongs to the Special Issue Innovative Research and Applications in Hydrodynamics and Flow Control)
19 pages, 4765 KiB  
Article
Design of a Fiber Temperature and Strain Sensor Model Using a Fiber Bragg Grating to Monitor Road Surface Conditions
by Gulzhan Kashaganova, Ainur Kozbakova, Timur Kartbayev, Kulzhan Togzhanova, Zhuldyz Alimseitova and Gani Sergazin
Inventions 2024, 9(5), 100; https://doi.org/10.3390/inventions9050100 - 13 Sep 2024
Cited by 1 | Viewed by 1102
Abstract
In this paper, the types and principles of operation of fiber sensors based on fiber Bragg gratings (FBGs) are investigated. The influence of strain and temperature on the characteristics of FBGs is considered, and a method for the simultaneous measurement of these parameters [...] Read more.
In this paper, the types and principles of operation of fiber sensors based on fiber Bragg gratings (FBGs) are investigated. The influence of strain and temperature on the characteristics of FBGs is considered, and a method for the simultaneous measurement of these parameters is presented. Laboratory studies were carried out in the temperature range from +18 °C to +135 °C with an incremental step of 5 °C, with the actual temperature not deviating by more than ±0.5 °C. From the data obtained, the Bragg wavelength–temperature relationships were plotted, which showed a linear increase in wavelength with increasing temperature. This study shows that the use of two FBGs with a different sensitivity to temperature and strain allowed for the simultaneous measurement of both parameters. Numerical models created in the MATLAB R2022b environment confirmed the high accuracy and precision of the measurements. The FBG-based sensors demonstrated a robust performance in harsh environments, withstanding temperatures of up to 160 °C and high humidity, making them applicable in various industries and sciences. This work confirms that FBGs are a promising tool for accurate temperature and strain measurements, providing reliable results in harsh environments. Full article
(This article belongs to the Section Inventions and Innovation in Advanced Manufacturing)
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13 pages, 5890 KiB  
Article
Composite Modified Graphite Felt Anode for Iron–Chromium Redox Flow Battery
by Sheng Wu, Haotian Zhu, Enrui Bai, Chongyang Xu, Xiaoyin Xie and Chuanyu Sun
Inventions 2024, 9(5), 98; https://doi.org/10.3390/inventions9050098 - 9 Sep 2024
Viewed by 1143
Abstract
The iron–chromium redox flow battery (ICRFB) has a wide range of applications in the field of new energy storage due to its low cost and environmental protection. Graphite felt (GF) is often used as the electrode. However, the hydrophilicity and electrochemical activity of [...] Read more.
The iron–chromium redox flow battery (ICRFB) has a wide range of applications in the field of new energy storage due to its low cost and environmental protection. Graphite felt (GF) is often used as the electrode. However, the hydrophilicity and electrochemical activity of GF are poor, and its reaction reversibility to Cr3+/Cr2+ is worse than Fe2+/Fe3+, which leads to the hydrogen evolution side reaction of the negative electrode and affects the efficiency of the battery. In this study, the optimal composite modified GF (Bi-Bio-GF-O) electrode was prepared by using the optimal pomelo peel powder modified GF (Bio-GF-O) as the matrix and further introducing Bi3+. The electrochemical performance and material characterization of the modified electrode were analyzed. In addition, using Bio-GF-O as the positive electrode and Bi-Bio-GF-O as the negative electrode, the high efficiency of ICRFB is realized, and the capacity attenuation is minimal. When the current density is 100 mA·cm−2, after 100 cycles, the coulomb efficiency (CE), voltage efficiency (VE), and energy efficiency (EE) were 97.83%, 85.21%, and 83.36%, respectively. In this paper, the use of pomelo peel powder and Bi3+ composite modified GF not only promotes the electrochemical performance and reaction reversibility of the negative electrode but also improves the performance of ICRFB. Moreover, the cost of the method is controllable, and the process is simple. Full article
(This article belongs to the Special Issue Advanced Electrode Material for Electrochemical Production Conversion and Storage of Energy)
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24 pages, 3113 KiB  
Article
Pressure Capacity Assessment of L-PBF-Produced Microchannel Heat Exchangers
by Jiabao An, Luyao Guo, Junjia Zou, Keliang Zhang, Yiheng Zhong, Taimingwang Liu, Long Huang and Yi Chen
Inventions 2024, 9(5), 97; https://doi.org/10.3390/inventions9050097 - 6 Sep 2024
Viewed by 1048
Abstract
Laser powder bed fusion (L-PBF) manufacturing technology is an emerging field of research that focuses on evaluating constraints in printed products. This study highlights the importance of considering various factors, such as mechanical properties and support structures, during the design phase, particularly in [...] Read more.
Laser powder bed fusion (L-PBF) manufacturing technology is an emerging field of research that focuses on evaluating constraints in printed products. This study highlights the importance of considering various factors, such as mechanical properties and support structures, during the design phase, particularly in the context of microchannel heat exchangers where all limiting factors are critical. This paper presents a methodology for analyzing channel pressure limitations and examines the impact of pipe porosity on the loss of mechanical properties. A combination of simulation experiments and pressure capacity tests is used to elucidate the pressure distribution characteristics of microchannel flat tubes and their true pressure capacity. This study also explores potential methods for improving the performance of L-PBF-printed microchannel flat tubes. The results and the development of the experimental setup are summarized. Full article
(This article belongs to the Special Issue Revolutionizing Manufacturing: Advances in Additive Manufacturing Technologies)
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38 pages, 6726 KiB  
Article
Exploring the Inhibitory Efficacy of Resokaempferol and Tectochrysin on PI3Kα Protein by Combining DFT and Molecular Docking against Wild-Type and H1047R Mutant Forms
by Cristina Paraschiv, Steluța Gosav, Catalina Mercedes Burlacu and Mirela Praisler
Inventions 2024, 9(5), 96; https://doi.org/10.3390/inventions9050096 - 5 Sep 2024
Viewed by 1067
Abstract
This study explores the inhibitory potential of the flavonoids resokaempferol and tectochrysin against both wild-type and H1047R mutant forms of PI3Kα, aiming to expand the repertoire of targeted cancer therapies. Employing an array of computational techniques, including Density Functional Theory (DFT), calculations of [...] Read more.
This study explores the inhibitory potential of the flavonoids resokaempferol and tectochrysin against both wild-type and H1047R mutant forms of PI3Kα, aiming to expand the repertoire of targeted cancer therapies. Employing an array of computational techniques, including Density Functional Theory (DFT), calculations of electronic parameters such as the energies of the frontier molecular orbitals, Molecular Electrostatic Potential (MEP) mapping, and Molecular Docking, we investigate in detail the molecular interactions of these compounds with the PI3Kα kinase. Our findings, corroborated by DFT calculations performed based on the B3LYP (Becke, three-parameter, Lee-Yang-Parr) hybrid functional and the 6-311G++(d,p) basis set, align well with experimental benchmarks and indicate substantial inhibitory efficacy. Further analysis of chemical potential and bioavailability confirmed the drug-like attributes of these flavonoids. Binding affinity and selectivity were rigorously assessed through self-docking and cross-docking against the PIK3CA PDB structures 7K71 and 8TS9. The most promising interactions were validated using Pairwise Structure Alignment and MolProbity analysis of all-atom contacts and geometry. Collectively, these results highlight the flavonoids’ potential as PI3Kα inhibitors and exemplify the utility of natural compounds in the development of precise anticancer treatments. Full article
(This article belongs to the Section Inventions and Innovation in Design, Modeling and Computing Methods)
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10 pages, 404 KiB  
Article
Anisotropic k-ϵ Model Based on General Principles of Statistical Turbulence
by J. J. H. Brouwers
Inventions 2024, 9(5), 95; https://doi.org/10.3390/inventions9050095 - 29 Aug 2024
Viewed by 758
Abstract
An upgrade is presented of a recently published model for the calculation of statistical averages of turbulent flow variables. Instead of empirical constructions, important parts of the model are based on general principles of statistical turbulence and physics. The upgrade concerns transparent and [...] Read more.
An upgrade is presented of a recently published model for the calculation of statistical averages of turbulent flow variables. Instead of empirical constructions, important parts of the model are based on general principles of statistical turbulence and physics. The upgrade concerns transparent and simplified descriptions of turbulent diffusion and Reynolds stresses which express their dependency of mean flow gradients in a direct manner. As before, prediction comparisons are satisfactory in relation to the results of DNS of channel flow. Implementation in a CFD code is straightforward and its application provides a significant improvement to the results of the widely used empirical basic k-ϵ model. Full article
(This article belongs to the Special Issue Innovative Research and Applications in Hydrodynamics and Flow Control, 2nd Edition)
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16 pages, 8548 KiB  
Review
CREC Optical-Fibre Sensors for Hydrodynamic Studies in Gas−Solid Fluidized Beds
by Nicolas Torres Brauer, Cesar Medina-Pedraza and Hugo de Lasa
Inventions 2024, 9(5), 94; https://doi.org/10.3390/inventions9050094 - 28 Aug 2024
Viewed by 801
Abstract
Optical probes can be employed in dense and dilute fluidized beds. Their application is useful to determine particle volume fraction, bubble velocity, bubble size, and solid segregation in dense-phase fluidized-bed reactors, as well as particle-cluster velocity, size, and shape, in downer/riser units. The [...] Read more.
Optical probes can be employed in dense and dilute fluidized beds. Their application is useful to determine particle volume fraction, bubble velocity, bubble size, and solid segregation in dense-phase fluidized-bed reactors, as well as particle-cluster velocity, size, and shape, in downer/riser units. The CREC-UWO team has developed a unique and miniaturized CREC Optiprobes System (CREC-GS-OPS) equipped with a GRIN (graded refraction index) lens. The GRIN lens creates a small volume of high light irradiation by focusing a laser a few millimetres away from the front of the probe tip. This design minimizes sensor intrusiveness and, as a result, provides trustworthy measurements of hydrodynamic parameters. Through the application of the CREC-GS-OPS, advances have been achieved, leading to (a) the development of a “Y-back” unit with graphite ferrules that protects the optiprobes from fibre-optic stresses and prevents the loss of sensor calibration and (b) the establishment of statistically-based data analysis. It is envisioned that through the introduction of a few design changes, the CREC Optiprobes will be made suitable for high-temperature applications. This will allow the measurement of catalyst flow recirculation (among other measurements), in industrial-scale fluidized-bed catalytic cracking units involving fluidized riser crackers and catalyst regenerators. Full article
(This article belongs to the Special Issue Inventions and Innovations in Optical Sensing Materials and Devices)
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32 pages, 26241 KiB  
Review
A Study on the Impact of Different PV Model Parameters and Various DC Faults on the Characteristics and Performance of the Photovoltaic Arrays
by Khaled Ibrahim Baradieh, Muhammad Ammirrul Atiqi Mohd Zainuri, Nor Azwan Mohamed Kamari, Huda Abdullah, Yushaizad Yusof, Mohd Asyraf Zulkifley and Mohsin Ali Koondhar
Inventions 2024, 9(5), 93; https://doi.org/10.3390/inventions9050093 - 27 Aug 2024
Cited by 1 | Viewed by 1339
Abstract
PV systems play a vital role in the global renewable energy sector, and they require accurate modeling and reliable performance to maximize the output power. This research presents a thorough analysis and discussions on the effects of different PV models’ parameters and certain [...] Read more.
PV systems play a vital role in the global renewable energy sector, and they require accurate modeling and reliable performance to maximize the output power. This research presents a thorough analysis and discussions on the effects of different PV models’ parameters and certain specific faults on the performance and behavior of the photovoltaic systems under different temperature and irradiation conditions. It provides a detailed analysis of how several parameters affect the performance of the PV arrays, for instance, the series resistance, shunt resistance, photocurrent, reverse saturation current, and the diode ideality factor. These parameters were extracted mathematically and verified with the help of wide-ranging simulations and practical experiments. Additionally, the investigation of the effect of DC faults, including line-to-line, line-to-ground, partial shading, and complete shading faults on PV arrays, provides important fundamentals for fault detection and classification, thus improving the efficiency and protection of PV systems. It can, therefore, be stated that the outcomes of this research will assist in the enhancement of PV systems in terms of design, operation, and maintainability of photovoltaic plants, as well as contribute positively to the advancement of sustainable solar energy technology. Full article
(This article belongs to the Section Inventions and Innovation in Electrical Engineering/Energy/Communications)
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13 pages, 1792 KiB  
Article
Parametric Optimization of Entropy Generation in Hybrid Nanofluid in Contracting/Expanding Channel by Means of Analysis of Variance and Response Surface Methodology
by Ahmad Zeeshan, Rahmat Ellahi, Muhammad Anas Rafique, Sadiq M. Sait and Nasir Shehzad
Inventions 2024, 9(5), 92; https://doi.org/10.3390/inventions9050092 - 27 Aug 2024
Cited by 3 | Viewed by 895
Abstract
This study aims to propose a central composite design (CCD) combined with response surface methodology (RSM) to create a statistical experimental design. A new parametric optimization of entropy generation is presented. The flow behavior of magnetohydrodynamic hybrid nanofluid (HNF) flow through two flat [...] Read more.
This study aims to propose a central composite design (CCD) combined with response surface methodology (RSM) to create a statistical experimental design. A new parametric optimization of entropy generation is presented. The flow behavior of magnetohydrodynamic hybrid nanofluid (HNF) flow through two flat contracting expanding plates of channel alongside radiative heat transmission was considered. The lower fixed plate was externally heated whereas the upper porous plate was cooled by injecting a coolant fluid with a uniform velocity inside the channel. The resulting equations were solved by the Homotopic Analysis Method using MATHEMATICA 10 and Minitab 17.1. The design consists of several input factors, namely a magnetic field parameter (M), radiation parameter (N) and group parameter (Br/A1). To obtain the values of flow response parameters, numerical experiments were used. Variables, especially the entropy generation (Ne), were considered for each combination of design. The resulting RSM empirical model obtained a high coefficient of determination, reaching 99.97% for the entropy generation number (Ne). These values show an excellent fit of the model to the data. Full article
(This article belongs to the Section Inventions and Innovation in Energy and Thermal/Fluidic Science)
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