Journal Description
Inventions
Inventions
is an international, scientific, peer-reviewed, open access journal published bimonthly online by MDPI.
- Open Access— free for readers, with article processing charges (APC) paid by authors or their institutions.
- High Visibility: indexed within Scopus, ESCI (Web of Science), Inspec, and other databases.
- Journal Rank: CiteScore - Q1 (General Engineering)
- Rapid Publication: manuscripts are peer-reviewed and a first decision is provided to authors approximately 17.4 days after submission; acceptance to publication is undertaken in 4.5 days (median values for papers published in this journal in the second half of 2023).
- Recognition of Reviewers: reviewers who provide timely, thorough peer-review reports receive vouchers entitling them to a discount on the APC of their next publication in any MDPI journal, in appreciation of the work done.
Impact Factor:
3.4 (2022);
5-Year Impact Factor:
3.5 (2022)
Latest Articles
Satellite Thermal Management Pump Impeller Design and Optimization
Inventions 2024, 9(3), 54; https://0-doi-org.brum.beds.ac.uk/10.3390/inventions9030054 - 06 May 2024
Abstract
This study presents a numerical approach to the design and optimization of centrifugal impellers used in the pumps of active thermal control systems of spacecraft. Although launch costs have shrunk in the last decade, the performance requirements, such as efficiency and reliability, have
[...] Read more.
This study presents a numerical approach to the design and optimization of centrifugal impellers used in the pumps of active thermal control systems of spacecraft. Although launch costs have shrunk in the last decade, the performance requirements, such as efficiency and reliability, have increased, as such systems are required to work up to 15 years, depending on the mission. To that effect, our paper deals with the first step in this pump design, namely the hydraulic optimization of the impeller. Constructively, this type of impeller allows for certain balancing systems and labyrinth seals to be applied in a more effective way, as well as allowing for additive manufacturing methods to be used—however, details regarding these aspects are beyond the scope of the current paper. By combining empirical formulas, computational fluid dynamics (CFD) analysis, and artificial neural networks (ANNs), the research focuses on achieving high efficiency and fast manufacturing. A series of geometries have been sized and validated using steady-state RANS (Reynolds Averaged Navier-Stokes) simulations, leading to the identification of the most efficient configuration. Subsequent optimization using an ANN resulted in a refined impeller design with notable improvements in hydraulic performance: a 3.55% increase in efficiency and a 7.9% increase in head. Key parameters influencing impeller performance, including blade number, incidence, and backsweep angles, are identified. This approach offers a comprehensive method to address the evolving requirements of space missions and contributes to the advancement of centrifugal pump technology in the space domain.
Full article
(This article belongs to the Special Issue New Sights in Fluid Mechanics and Transport Phenomena)
►
Show Figures
Open AccessArticle
A Modeling-Based Flammable Risk Treatment of Refrigerant Leakage from a Commercial R-290 Refrigeration Machine
by
Mingkan Zhang, Vishaldeep Sharma and Praveen Cheekatamarla
Inventions 2024, 9(3), 53; https://0-doi-org.brum.beds.ac.uk/10.3390/inventions9030053 - 04 May 2024
Abstract
Because of serious concerns about global warming, manufacturers have started phasing out high global warming potential (GWP) refrigerants in commercial refrigeration equipment (e.g., R-134a). As a potential replacement, propane (R-290) is an environmentally friendly refrigerant for commercial refrigeration equipment because its GWP is
[...] Read more.
Because of serious concerns about global warming, manufacturers have started phasing out high global warming potential (GWP) refrigerants in commercial refrigeration equipment (e.g., R-134a). As a potential replacement, propane (R-290) is an environmentally friendly refrigerant for commercial refrigeration equipment because its GWP is only three. However, propane is flammable and is therefore classified as a Class A3 refrigerant per ASHRAE Standards, so safety is a very important consideration when propane-based equipment is designed and deployed in buildings. In the event of a refrigerant leak, flammability of the refrigerant depends on the refrigerant’s local concentration, which is highly affected by the indoor air environment, including temperature and air flow. In this study, a ventilation system attached to a commercial R-290 refrigeration device was designed to eliminate the flammability risk. Moreover, a computational fluid dynamics (CFD) model was developed to investigate the refrigerant leak, thereby evaluating effects of the ventilation system. The CFD model can visualize the flammable zones owing to the leak.
Full article
(This article belongs to the Special Issue Thermodynamic and Technical Analysis for Sustainability (Volume 3))
►▼
Show Figures
Figure 1
Open AccessArticle
Concept of a Peripheral-Free Electrified Monorail System (PEMS) for Flexible Material Handling in Intralogistics
by
Marvin Sperling, Timo Kurschilgen and Pietro Schumacher
Inventions 2024, 9(3), 52; https://0-doi-org.brum.beds.ac.uk/10.3390/inventions9030052 - 30 Apr 2024
Abstract
With the emergence of Industry 4.0 in intralogistics, the need for flexible material handling solutions is increasing. While conventional conveyor systems are often too inflexible to meet changing requirements. Automated guided vehicles offer an answer, additional solutions are required for companies relying on
[...] Read more.
With the emergence of Industry 4.0 in intralogistics, the need for flexible material handling solutions is increasing. While conventional conveyor systems are often too inflexible to meet changing requirements. Automated guided vehicles offer an answer, additional solutions are required for companies relying on already busy and crowded shop floors. This paper presents a concept for a periphery-free electrified monorail system (PEMS) that enables flexible material transport with minimal floor requirements. The PEMS is based on classic electrified monorail technology, and requires no additional peripheral devices within the rail system. Installation and maintenance costs are kept to a minimum through simplified branching elements and a battery-powered energy supply for the vehicles. The modular design of the rail elements further allows transport on standardized Euro-pallets. Moreover, a taxonomy for evaluating the passivity of branching elements of electrified monorail systems is introduced. The functionality of the PEMS was validated by conducting real experiments using a prototype, The results show that the PEMS provides high flexibility in terms of layout design and usage, allowing for fast adaption to the changing requirements of intralogistics.
Full article
(This article belongs to the Special Issue Revolutionizing Mobility: Unleashing the Power of Software-Defined Networking for Electric Vehicle Communication)
►▼
Show Figures
Figure 1
Open AccessArticle
Hydraulic Drilling Nozzle Design and Research
by
Przemysław Toczek, Rafał Wiśniowski, Albert Złotkowski and Wojciech Teper
Inventions 2024, 9(3), 51; https://0-doi-org.brum.beds.ac.uk/10.3390/inventions9030051 - 29 Apr 2024
Abstract
In light of the European Union’s zero-emissions policy and the growing demand for energy associated with technological advances, it is necessary to consider adopting technologies and innovative solutions that simultaneously reduce greenhouse gas emissions while increasing potential extraction from existing hydrocarbon deposits, for
[...] Read more.
In light of the European Union’s zero-emissions policy and the growing demand for energy associated with technological advances, it is necessary to consider adopting technologies and innovative solutions that simultaneously reduce greenhouse gas emissions while increasing potential extraction from existing hydrocarbon deposits, for example. This can result in increased production from deposits with low reservoir energy values or those in which the energy value does not allow the resource to be exploited on its own. By using a hydraulic drilling nozzle that harnesses the hydraulic energy of the fluid stream for workover, the possibility of increasing the contact between the reservoir layer and the producing well increases in direct proportion to the number of small-diameter radial wells drilled with a hydraulic rotary head from a horizontal well toward the reservoir layer. The main aspect of this paper is to outline an algorithm for the design of rotary drilling heads to maximize the use of the hydraulic energy from fluid streams flowing from the face of innovative drilling tools. The presented design algorithm allows changing the mutual position between the holes in the face section and the angle of the holes with respect to the longitudinal axis of the designed hydraulic rotary nozzle, simplifying the design work. The use of the rotary head developed using this algorithm enables seamless drilling in rocks with compressive strength Rc = 50 MPa, considering the drilling progress at ROP = 4 mm/s.
Full article
(This article belongs to the Special Issue Innovative Research and Applications in Hydrodynamics and Flow Control, 2nd Edition)
►▼
Show Figures
Figure 1
Open AccessArticle
Barriers and Facilitators for Usage of Self-Compacting Concrete—An Interview Study
by
Inga Mikhaltchouk, Jörgen Eklund and Mikael Forsman
Inventions 2024, 9(3), 50; https://0-doi-org.brum.beds.ac.uk/10.3390/inventions9030050 - 29 Apr 2024
Abstract
Workers in the construction industry must endure different weather conditions, long working hours, and engage in repetitive and strenuous jobs with unrealistic deadlines. Sick leaves, caused by accidents and by work-related diseases, are common in the construction industry. Hand–arm vibration from hand-held power
[...] Read more.
Workers in the construction industry must endure different weather conditions, long working hours, and engage in repetitive and strenuous jobs with unrealistic deadlines. Sick leaves, caused by accidents and by work-related diseases, are common in the construction industry. Hand–arm vibration from hand-held power tools is a cause of significant ill health (disorders of the blood vessels, nerves, and joints). Self-compacting concrete (SCC) is a fluid concrete and does not need to be vibrated. Despite the health advantages of SCC, its market share in Sweden is lower than in comparable countries. The aim of this article is to describe views, opinions, and knowledge concerning the work environment and health in concrete casting and to identify barriers and facilitators of SCC usage. Semi-structured interviews were conducted with 24 interviewees from the construction industry in Sweden. The answers were analysed from a human–technology–organisation (HTO) perspective in order to identify barriers and facilitators for a broader usage of SCC. The results indicate that knowledge about SCC is low within the Swedish construction industry, including educational institutions; when SCC is chosen, it is chosen exclusively due to its technical characteristics, and not because it eliminates vibrations. Barriers to a broader usage of SCC comprise an incomplete knowledge base, clients who never choose it, recipes that are said to be too demanding, and workplace traditions. Facilitators comprise large companies investing in knowledge development about SCC and engaged persons promoting it. This study used an HTO-based model (BTOH) to identify barriers and facilitators for a broader usage of SCC, thus contributing to a deeper understanding of reasons for the low usage of SCC and ways of increasing it.
Full article
(This article belongs to the Section Inventions and Innovation in Design, Modeling and Computing Methods)
►▼
Show Figures
Figure 1
Open AccessCommunication
Coverage Performance of Non-Lambertian Underwater Wireless Optical Communications for 6G Internet of Things
by
Jupeng Ding, Chih-Lin I, Jintao Wang and Jian Song
Inventions 2024, 9(3), 49; https://0-doi-org.brum.beds.ac.uk/10.3390/inventions9030049 - 28 Apr 2024
Abstract
In medium- and short-range underwater application scenarios, thanks to the superior performance in transmission bandwidth, link latency, and security, underwater wireless optical communication (UWOC) is growing to be a promising complement to the mature underwater acoustic communication technique. In order to extend the
[...] Read more.
In medium- and short-range underwater application scenarios, thanks to the superior performance in transmission bandwidth, link latency, and security, underwater wireless optical communication (UWOC) is growing to be a promising complement to the mature underwater acoustic communication technique. In order to extend the future 6G Internet of Things (IOT) to various challenging and valuable underwater scenarios, the underwater spatial coverage and transmission performance has been actively discussed in typical seawater environments. However, almost all current works focus on underwater scenarios including light-emitting diode (LED) transmitters with well-known Lambertian optical beams and fail to characterize the scenarios adopting LED transmitters with distinctive non-Lambertian beam patterns. For addressing this limitation, in this article, the coverage performance of non-Lambertian UWOC for 6G is analyzed and illustrated. Furthermore, the switchable optical beam configuration scheme is proposed and estimated for UWOC. Numerical results illustrate that, compared with about 15.42 dB signal-to-noise ratio (SNR) fluctuation amplitude for UWOC with baseline Lambertian optical beam configuration, the corresponding SNR fluctuation amplitudes of UWOC based with two typical non-Lambertian optical beams are 8.71 dB and 24.60 dB. Furthermore, once the receiver depth is increased to 6.0 m, the SNR fluctuation amplitude for the above three UWOC coverage with distinct beam configuration could be reduced to 5.61 dB, 1.58 dB, and 10.33 dB, respectively.
Full article
(This article belongs to the Special Issue Recent Advances in Visible Light Communication and Optical Wireless Information Systems)
►▼
Show Figures
Figure 1
Open AccessArticle
Improving the Hydrodynamic Performance of Underwater Tags for Blue Shark Monitoring
by
José Azevedo, Violeta Carvalho, Tiago Bartolomeu, Ana Arieira, Senhorinha F. Teixeira and José C. Teixeira
Inventions 2024, 9(3), 48; https://0-doi-org.brum.beds.ac.uk/10.3390/inventions9030048 - 26 Apr 2024
Abstract
The use of tag devices in marine environments has become indispensable in attaining a better understanding of marine life and contributing to conservation efforts. However, the successful deployment and operation of underwater tags both depend significantly on their hydrodynamic characteristics, particularly their resistance
[...] Read more.
The use of tag devices in marine environments has become indispensable in attaining a better understanding of marine life and contributing to conservation efforts. However, the successful deployment and operation of underwater tags both depend significantly on their hydrodynamic characteristics, particularly their resistance to motion and stability in various environmental conditions. Herein, a comprehensive study on the hydrodynamic characteristics and optimization of an underwater tag designed for monitoring blue sharks is presented. Firstly, a validation process is conducted by comparing the computational fluid dynamics (CFD) results with the experimental data from Myring’s study, focusing on the resistance characteristics of the tag’s body and the impact of various operational conditions. Subsequently, the validated CFD model is applied to assess the hydrodynamic performance of the tag under different flow conditions, velocities, and angles of attack. Through iterative simulations, including mesh independence studies and boundary condition adjustments, the study identifies key parameters influencing the tag’s resistance and stability. Furthermore, the paper proposes and implements design modifications, including the incorporation of stabilizing fins, aimed at minimizing resistance and improving the tag’s equilibrium position. The effectiveness of these design enhancements is demonstrated through a comparative analysis of resistance and pitching moments for both preliminary and optimized tag configurations. Overall, the study provides valuable insights into the hydrodynamic behavior of underwater tags and offers practical recommendations for optimizing their design to minimize interference with the movement of tagged marine animals.
Full article
(This article belongs to the Special Issue Innovative Research and Applications in Hydrodynamics and Flow Control, 2nd Edition)
►▼
Show Figures
Figure 1
Open AccessArticle
Detection and Analysis of Aircraft Composite Material Structures Using UAV
by
Kuo-Chien Liao, Jian-Liang Liou, Muhamad Hidayat, Hung-Ta Wen and Hom-Yu Wu
Inventions 2024, 9(3), 47; https://0-doi-org.brum.beds.ac.uk/10.3390/inventions9030047 - 26 Apr 2024
Abstract
Pre-flight inspection and maintenance are essential prerequisites for aviation safety. This study focused on developing a real-time monitoring system designed to assess the condition of composite material structures on the exterior of aircraft. Implementing such a system can reduce operational costs, enhance flight
[...] Read more.
Pre-flight inspection and maintenance are essential prerequisites for aviation safety. This study focused on developing a real-time monitoring system designed to assess the condition of composite material structures on the exterior of aircraft. Implementing such a system can reduce operational costs, enhance flight safety, and increase aircraft availability. This study aims to detect defects in aircraft fuselages manufactured from composite materials by applying image visual recognition technology. This study integrated a drone and an infrared camera for real-time image transmission to ground stations. MATLAB image analysis software (MATLAB 2020b) was used to analyze infrared (IR) images and detect structural defects in the aircraft’s appearance. This methodology was based on the inspection of damaged engine cowlings. The developed approach compares composite material conditions with known defects before and after repair, considering mechanical performance, defect size, and strength. Simultaneously, tests were conducted on various composite material panels with unknown defects, yielding favorable results. This study underscores an integrated system offering rapid detection, real-time feedback, and analysis, effectively reducing time, and potential hazards associated with high-altitude operations. Furthermore, it addresses blind spots in aircraft inspections, contributing to effective flight safety maintenance.
Full article
(This article belongs to the Special Issue Quadrotor UAV with Advanced Applications)
►▼
Show Figures
Figure 1
Open AccessArticle
Experimental Research on an Afterburner System Fueled with Hydrogen–Methane Mixtures
by
Florin Gabriel Florean, Andreea Mangra, Marius Enache, Marius Deaconu, Razvan Ciobanu and Razvan Carlanescu
Inventions 2024, 9(3), 46; https://0-doi-org.brum.beds.ac.uk/10.3390/inventions9030046 - 24 Apr 2024
Abstract
A new afterburner installation is proposed, fueled with pure hydrogen (100%H2) or hydrogen–methane mixtures (60% H2 + 40% CH4, 80% H2 + 20% CH4) for use in cogeneration applications. Two prototypes (P1 and P2) with the
[...] Read more.
A new afterburner installation is proposed, fueled with pure hydrogen (100%H2) or hydrogen–methane mixtures (60% H2 + 40% CH4, 80% H2 + 20% CH4) for use in cogeneration applications. Two prototypes (P1 and P2) with the same expansion angle (45 degrees) were developed and tested. P1 was manufactured by the classic method and P2 by additive manufacturing. Both prototypes were manufactured from Inconel 625. During the tests, analysis of flue gas (CO2, CO, and NO concentration), PIV measurements, and noise measurements were conducted. The flue gas analysis emphasizes that the behavior of the two tested prototypes was very similar. For all three fuels used, the CO2 concentration levels were slightly lower in the case of the additive-manufactured prototype P2. The CO concentration levels were significantly higher in the case of the additive-manufactured prototype P2 when 60% H2/40% CH4 and 80% H2/20% CH4 mixtures were used as fuel. When pure H2 was used as fuel, the measured data suggest that no additional CO was produced during the combustion process, and the level of CO was similar to that from the Garrett micro gas turbine in all five measuring points. The NO emissions gradually decreased as the percentage of H2 in the fuel mixture increased. The NO concentration was significantly lower in the case of the additive-manufactured prototype (P2) in comparison with the classic manufactured prototype (P1). Examining the data obtained from the PIV measurements of the flow within the mixing region shows that the highest axial velocity component value on the centerline was measured for the P1 prototype. The acoustic measurements showed that a higher H2 concentration led to a reduction in noise of approximately 1.5 dB for both afterburner prototypes. The outcomes reveal that the examined V-gutter flame holder prototype flow was smooth, without any perpendicular oscillations, without chaotic motions or turbulent oscillations to the flow direction, across all tested conditions, keeping constant thermal power.
Full article
(This article belongs to the Special Issue Thermodynamic and Technical Analysis for Sustainability (Volume 3))
►▼
Show Figures
Figure 1
Open AccessArticle
A Novel Hybrid Ultrasound Abrasive-Driven Electrochemical Surface Finishing Technique for Additively Manufactured Ti6Al4V Parts
by
Manyou Sun and Ehsan Toyserkani
Inventions 2024, 9(2), 45; https://0-doi-org.brum.beds.ac.uk/10.3390/inventions9020045 - 19 Apr 2024
Abstract
Poor surface quality is one of the drawbacks of metal parts made by additive manufacturing (AM)—they normally possess relatively high surface roughness and different types of surface irregularities. Post-processing operations are usually needed to reduce the surface roughness to have ready-to-use parts. Among
[...] Read more.
Poor surface quality is one of the drawbacks of metal parts made by additive manufacturing (AM)—they normally possess relatively high surface roughness and different types of surface irregularities. Post-processing operations are usually needed to reduce the surface roughness to have ready-to-use parts. Among all the surface treatment techniques, electrochemical polishing has the highest finishing efficiency and flexibility. However, although the average surface roughness can be reduced effectively (more than 80% roughness reduction), large-scale surface waviness still remains an issue when finishing metal AM parts. To maintain the finishing efficiency while reducing the surface waviness, a novel hybrid surface finishing technique is designed, which involves the combination of electropolishing, ultrasonic vibration, and abrasion. Preliminary experiments to prove the feasibility of novel hybrid finishing methods were conducted on Ti6Al4V coupons manufactured via laser powder bed fusion (LPBF). Electropolishing, a combination of ultrasound and abrasion, and hybrid finishing were conducted for process optimization and comparison purposes. The effects of the voltage, inter-electrode gap, temperature, ultrasonic amplitude, abrasive concentration, and processing time were studied and optimized. When similar optimal arithmetic mean height values (Sa ≈ 1 μm) are achieved for both processes, the arithmetic mean waviness values (Wa) obtained from hybrid finishing are much less than those from sole electropolishing after the same processing time, with the amount being 61.7% less after 30 min and 40.0% after 45 min.
Full article
(This article belongs to the Special Issue Revolutionizing Manufacturing: Advances in Additive Manufacturing Technologies)
►▼
Show Figures
Figure 1
Open AccessArticle
A Modified Reduced-Order Generalized Integrator–Frequency-Locked Loop-Based Sensorless Vector Control Scheme Including the Maximum Power Point Tracking Algorithm for Grid-Connected Squirrel-Cage Induction Generator Wind Turbine Systems
by
Tuynh Van Pham and Anh Tan Nguyen
Inventions 2024, 9(2), 44; https://0-doi-org.brum.beds.ac.uk/10.3390/inventions9020044 - 18 Apr 2024
Abstract
In this paper, an improved speed sensorless control method including the maximum power point tracking (MPPT) algorithm for grid-connected squirrel-cage induction generator (SCIG) wind turbine systems using modified reduced-order generalized integrator (ROGI)–frequency-locked loop (FLL) with the DC offset compensation capability is proposed. The
[...] Read more.
In this paper, an improved speed sensorless control method including the maximum power point tracking (MPPT) algorithm for grid-connected squirrel-cage induction generator (SCIG) wind turbine systems using modified reduced-order generalized integrator (ROGI)–frequency-locked loop (FLL) with the DC offset compensation capability is proposed. The rotor flux linkages are estimated by the modified ROGI-FLL-based observer, of which the inputs are d-q axis rotor EMFs, and hence the position of rotor flux linkage can be obtained directly based on these estimated flux linkages using the arc tangent function. The DC offset in the estimated rotor flux linkages, which can cause oscillations in estimated rotor speed, leading to oscillations in SCIG stator active power due to power signal feedback (PSF)-MPPT algorithm, can be significantly reduced using the DC offset compensators included in modified ROGI-FLL structure. Moreover, the negative effects of high-frequency components on the performance of the rotor flux linkage estimation can be remarkably mitigated owing to the excellent high-frequency component rejection capability of ROGI. The dynamic response analysis of the modified ROGI-FLL with DC offset compensators is provided as well. The feasibility of the proposed method has been demonstrated in comparison with dual SOGI-FLL with DC offset compensator-based existing method.
Full article
(This article belongs to the Special Issue Innovative Strategy of Protection and Control for the Grid)
►▼
Show Figures
Figure 1
Open AccessEditorial
From Sensing Technology towards Digital Twin in Applications
by
Jianxiong Zhu, Bairong Sun, Luyu Jia and Haibing Hu
Inventions 2024, 9(2), 43; https://0-doi-org.brum.beds.ac.uk/10.3390/inventions9020043 - 17 Apr 2024
Abstract
Sensing technology drives innovation in digital technology, especially in data acquisition [...]
Full article
(This article belongs to the Special Issue From Sensing Technology towards Digital Twin in Applications)
Open AccessArticle
Enhanced Heat Transfer in Thermoelectric Generator Heat Exchanger for Sustainable Cold Chain Logistics: Entropy and Exergy Analysis
by
Yunchi Fu and Yanzhe Li
Inventions 2024, 9(2), 42; https://0-doi-org.brum.beds.ac.uk/10.3390/inventions9020042 - 15 Apr 2024
Abstract
This study investigates the application of thermoelectric power generation devices in conjunction with cold chain logistics transport vehicles, focusing on their efficiency and performance. Our experimental results highlight the impact of thermoelectric module characteristics, such as thermal conductivity and the filling thickness of
[...] Read more.
This study investigates the application of thermoelectric power generation devices in conjunction with cold chain logistics transport vehicles, focusing on their efficiency and performance. Our experimental results highlight the impact of thermoelectric module characteristics, such as thermal conductivity and the filling thickness of copper foam, on the energy utilization efficiency of the system. The specific experimental setup involved a simulated logistics cold chain transport vehicle exhaust waste heat recovery thermoelectric power generation system, consisting of a high-temperature exhaust heat exchanger channel and two side cooling water tanks. Thermoelectric modules (TEMs) were installed between the heat exchanger and the water tanks to use the temperature difference and convert heat energy into electrical energy. The analysis demonstrates that using high-performance thermoelectric modules with a lower thermal conductivity results in better utilization of the temperature difference for power generation. Additionally, the insertion of porous metal copper foam within the heat exchanger channel enhances convective heat transfer, leading to an improved performance. Furthermore, the study examines the concepts of exergy and entropy generation, providing insights into the system energy conversion processes and efficiency. Overall, this research offers valuable insights for optimizing the design and operation of thermoelectric generators in cold chain logistics transport vehicles to enhance energy utilization and sustainability.
Full article
(This article belongs to the Special Issue Innovations in Heat Exchangers)
►▼
Show Figures
Figure 1
Open AccessArticle
The Expected Dynamics for the Extreme Wind and Wave Conditions at the Mouths of the Danube River in Connection with the Navigation Hazards
by
Alina Beatrice Răileanu, Liliana Rusu, Andra Marcu and Eugen Rusu
Inventions 2024, 9(2), 41; https://0-doi-org.brum.beds.ac.uk/10.3390/inventions9020041 - 12 Apr 2024
Abstract
The entrance in the Sulina channel in the Black Sea is the target area of this study. This represents the southern gate of the seventh Pan-European transport corridor, and it is usually subjected to high navigation traffic. The main objective of the work
[...] Read more.
The entrance in the Sulina channel in the Black Sea is the target area of this study. This represents the southern gate of the seventh Pan-European transport corridor, and it is usually subjected to high navigation traffic. The main objective of the work is to provide a more comprehensive picture concerning the past and future expected dynamics of the environmental matrix in this coastal area, including especially the extreme wind and wave conditions in connection with the possible navigation risks. The methodology considered assumes analyses performed at three different levels. First, an analysis of some in situ measurements at the zero-kilometer point of the Danube is carried out for the 15-year period of 2009–2023. Together with the maximum wind speed and the maximum value of the wind gusts, the water level variation was analyzed at this point. As a second step, the analysis is based on wind speed data provided by regional climate models. Two periods, each spanning 30 years, are considered. These are the recent past (1976–2005), when comparisons with ERA5 reanalysis data were also performed, and the near future (2041–2070), when two different models and three climate scenarios were considered. The focus was on the extreme wind speed values, performing comparisons between the past and future expected extreme winds. Finally, the third analysis is related to the wave conditions. Thus, using as a forcing factor each of the wind fields that was previously analyzed, simulations employing a spectral wave model were carried out. The wave modeling system was focused using three different computational domains with increasing resolution towards the target area, and the nearshore wave conditions were evaluated. The results show that both the extreme wind and wave conditions are expected to slightly increase in the future. Especially in the wintertime, strong wind fields are often expected in this area, with wind gusts exceeding more than 70% of the hourly average wind velocity. With regard to the waves, due to the complex nearshore phenomena, considerable enhancements in terms of significant wave heights are induced, and there is also an elevated risk of the occurrence of rogue waves. This work is still ongoing, and taking into account the high navigation risks highlighted, the next step would be to elaborate the risk assessment of severe shipping conditions, particularly related to the likelihood or probability of adverse conditions with the potential of generating hazardous situations in this coastal environment.
Full article
(This article belongs to the Special Issue Innovative Research and Applications in Hydrodynamics and Flow Control, 2nd Edition)
►▼
Show Figures
Figure 1
Open AccessArticle
Design, Construction and Programming of a Low-Cost Pulsed High-Voltage Direct Current Power Supply for the Electrophoretic Deposition of Silicon Carbide Mixed with Graphite and/or Alumina for Thermoelectric Applications
by
Juan Jesús Reyes Valdez, Edna Carina De la Cruz Terrazas and Eugenio Rodríguez González
Inventions 2024, 9(2), 40; https://0-doi-org.brum.beds.ac.uk/10.3390/inventions9020040 - 12 Apr 2024
Abstract
This document describes a proprietary design, construction, programming and testing of a low-cost pulsed high-voltage direct current (HVDC) power supply with an output of 430 V and power of 25 W. The design obtained allows costs to be reduced compared to commercial ones,
[...] Read more.
This document describes a proprietary design, construction, programming and testing of a low-cost pulsed high-voltage direct current (HVDC) power supply with an output of 430 V and power of 25 W. The design obtained allows costs to be reduced compared to commercial ones, highlighting that the manufacturing of this HVDC is easy to replicate. To demonstrate the operation of the pulsed power supply prototype, coatings of silicon carbide (SiC) and SiC mixed with graphite (C) and/or alumina (Al2O3) were made using the electrophoretic deposition (EPD) method. After processing, samples underwent a heat treatment at 500 °C to evaluate their thermoelectric (TE) efficiency. The samples were analysed via X-ray diffraction (XRD), scanning electron microscopy (SEM), Raman spectroscopy, Seebeck coefficient, electrical conductivity and thermal conductivity. The Seebeck coefficient, electrical conductivity and thermal conductivity were measured in a temperature range of 100–500 °C in a nitrogen (N2) atmosphere. The electrical conductivity of the SiC 6C-4Al sample was 0.65 S/cm at 500 °C, while the maximum Seebeck coefficient was 2500 μV/K of the SiC 6C-4Al sample at 200 °C. The thermal conductivity of SiC 6C-4Al was in the range of 0.35–0.37 W/m·K, which was much lower than the SiC sample free of alumina and graphite in the same measured temperature range. In conclusion, the SiC 6C-4Al sample presented the highest figure of merit with a ZT ≈ 0.01.
Full article
(This article belongs to the Section Inventions and Innovation in Applied Chemistry and Physics)
►▼
Show Figures
Figure 1
Open AccessArticle
Innovative Hybrid UAV Design, Development, and Manufacture for Forest Preservation and Acoustic Surveillance
by
Gabriel Petre Badea, Tiberius Florian Frigioescu, Madalin Dombrovschi, Grigore Cican, Marius Dima, Victoras Anghel and Daniel Eugeniu Crunteanu
Inventions 2024, 9(2), 39; https://0-doi-org.brum.beds.ac.uk/10.3390/inventions9020039 - 10 Apr 2024
Abstract
The research described in this paper focuses on the development of an innovative unmanned aerial vehicle (UAV) tailored for a specific mission: detecting the acoustic signature emitted by chainsaws, identifying deforestation, and reporting its location for legality assessment. Various calculations were conducted to
[...] Read more.
The research described in this paper focuses on the development of an innovative unmanned aerial vehicle (UAV) tailored for a specific mission: detecting the acoustic signature emitted by chainsaws, identifying deforestation, and reporting its location for legality assessment. Various calculations were conducted to determine the optimal solution, resulting in the choice of a fixed-wing UAV. A comparative analysis between tri-rotor and quadcopter systems was performed, leading to the selection of the tri-rotor configuration. The primary objective of this study is to design an innovative hybrid UAV concept with key features including a fixed-wing design and integrated VTOL (vertical takeoff and landing) capability in the experimental model. The aircraft has been constructed using advanced materials such as fiber-reinforced polymer composites, manufactured using both conventional and advanced techniques like continuous fiber additive manufacturing and the use of a polymer matrix. Additionally, the aerodynamic configuration is optimized to achieve a cruise speed of approximately 50 km/h and a flight autonomy exceeding 3 h. The UAV has been equipped with payloads for mounting sensors to collect meteorological data, and crucially, the VTOL system has been optimized to vectorize thrust for improved performance during the transition from hover to cruise flight. This paper details the entire manufacturing and assembly process of the drone, covering both the structural framework and associated electrical installations. A dedicated sound detection system is incorporated into the drone to identify chainsaw noise, with the aim of preventing deforestation.
Full article
(This article belongs to the Special Issue Quadrotor UAV with Advanced Applications)
►▼
Show Figures
Figure 1
Open AccessArticle
The Basic k-ϵ Model and a New Model Based on General Statistical Descriptions of Anisotropic Inhomogeneous Turbulence Compared with DNS of Channel Flow at High Reynolds Number
by
J. J. H. Brouwers
Inventions 2024, 9(2), 38; https://0-doi-org.brum.beds.ac.uk/10.3390/inventions9020038 - 08 Apr 2024
Abstract
Predictions are presented of mean values of statistical variables of large-scale turbulent flow of the widely used basic k- model, and of a new model, which is based on general statistical descriptions of turbulence. The predictions are verified against published results
[...] Read more.
Predictions are presented of mean values of statistical variables of large-scale turbulent flow of the widely used basic k- model, and of a new model, which is based on general statistical descriptions of turbulence. The predictions are verified against published results of direct numerical simulations (DNSs) of Navier–Stokes equations. The verification concerns turbulent channel flow at shear Reynolds numbers of 950, 2000, and . The basic k- model is largely based on empirical formulations accompanied by calibration constants. This contrasts with the new model, where descriptions of leading statistical quantities are based on the general principles of statistical turbulence at a large Reynolds number and stochastic theory. Predicted values of major output variables such as turbulent viscosity, diffusivity of passive admixture, temperature, and fluid velocities compare well with DNS for the new model. Significant differences are seen for the basic k- model.
Full article
(This article belongs to the Special Issue Innovative Research and Applications in Hydrodynamics and Flow Control, 2nd Edition)
►▼
Show Figures
Figure 1
Open AccessArticle
Modeling and Experimental Validation of Broad Input-Output Range Three-Voltage-Level Rectifier
by
Yarden Oren, Eliav Dahan, Aaron Shmaryahu, Yishai Kellerman, Moshe Sitbon, Shlomo Yaakov Gadelovits, Dmitry Baimel and Ilan Aharon
Inventions 2024, 9(2), 37; https://0-doi-org.brum.beds.ac.uk/10.3390/inventions9020037 - 29 Mar 2024
Abstract
A new type of single–conversion–step wide–input–range versatile step–up/down three–voltage–level power–factor correction stage is presented in this manuscript. The rectifier can operate both in continuous–conduction mode and discontinuous–conduction mode. First, the rectifier’s principle of operation is described, and then the innovative rectifier is analyzed
[...] Read more.
A new type of single–conversion–step wide–input–range versatile step–up/down three–voltage–level power–factor correction stage is presented in this manuscript. The rectifier can operate both in continuous–conduction mode and discontinuous–conduction mode. First, the rectifier’s principle of operation is described, and then the innovative rectifier is analyzed in continuous and discontinuous–conduction modes. After, an average model for the innovative rectifier is developed. Lastly, the proposed theory is experimentally validated using a multiplier–less dual–control–loop mode at discontinuous–conduction modes. It is shown that although no multiplier is used in the control circuitry, the power factor is near unity. It is revealed that the rectifier can swing the output voltage from 50 V to 900 V while the input voltage is 230 Vrms. Although the rectifier output has a split DC bus with three voltage levels, the required control effort is low, and the output voltage is balanced. The innovative topology suits any standard power–factor correction rectifier application, dual–stage low–voltage power supply, and three–level voltage supplement for low–harmonic inverters. Since the rectifier’s output–voltage swing is extremely wide, energy storage systems and electric vehicle batteries are suitable applications.
Full article
(This article belongs to the Special Issue Inventions in Power Trains for Electrical Vehicles)
►▼
Show Figures
Figure 1
Open AccessArticle
Characterization of Pig Vertebrae under Axial Compression Integrating Radiomic Techniques and Finite Element Analysis
by
Cristian A. Hernández-Salazar, Camilo E. Chamorro and Octavio A. González-Estrada
Inventions 2024, 9(2), 36; https://0-doi-org.brum.beds.ac.uk/10.3390/inventions9020036 - 28 Mar 2024
Abstract
The study of pig bones, due to their similarity with human tissues, has facilitated the development of technological tools that help in the diagnosis of diseases and injuries affecting the skeletal system. Radiomic techniques involving medical image segmentation, along with finite element analysis,
[...] Read more.
The study of pig bones, due to their similarity with human tissues, has facilitated the development of technological tools that help in the diagnosis of diseases and injuries affecting the skeletal system. Radiomic techniques involving medical image segmentation, along with finite element analysis, enable the detailed study of bone damage, loss of density, and mechanical functionality, which is a significant advancement in personalized medicine. This study involves conducting experimental tests on L3–L6 pig vertebrae under axial loading conditions. The mechanical properties of these vertebrae are analyzed, and the maximum loads they can sustain within the elastic range are determined. Additionally, three-dimensional models are generated by segmenting computerized axial tomography (CAT) scans of the vertebrae. Digital shadows of the vertebrae are constructed by assigning an anisotropic material model to the segmented geometries. Then, finite element analysis is performed to evaluate the elastic characteristics, stress, and displacement. The findings from the experimental data are then compared to the numerical model, revealing a strong correlation with differences of less than 0.8% in elastic modulus and 1.53% in displacement. The proposed methodology offers valuable support in achieving more accurate medical outcomes, employing models that serve as a diagnostic reference. Moreover, accurate bone modeling using finite element analysis provides valuable information to understand how implants interact with the surrounding bone tissue. This information is useful in guiding the design and optimization of implants, enabling the creation of safer, more durable, and biocompatible medical devices that promote optimal osseointegration and healing in the patient.
Full article
(This article belongs to the Special Issue Innovative Instrument Setting and Software Development for Organismic Biology and Behavior Analysis)
►▼
Show Figures
Figure 1
Open AccessArticle
Coordinated, Centralized, and Simultaneous Control of Fast Charging Stations and Distributed Energy Resources
by
Dener A. de L. Brandao, João M. S. Callegari, Danilo I. Brandao and Igor A. Pires
Inventions 2024, 9(2), 35; https://0-doi-org.brum.beds.ac.uk/10.3390/inventions9020035 - 25 Mar 2024
Abstract
The growing penetration of fast charging stations (FCSs) to electric vehicles (EVs) and distributed energy resources (DERs) in the electrical power system brings technical issue changes in the voltage profile throughout grid nodes and feeder current overload. The provision of ancillary services by
[...] Read more.
The growing penetration of fast charging stations (FCSs) to electric vehicles (EVs) and distributed energy resources (DERs) in the electrical power system brings technical issue changes in the voltage profile throughout grid nodes and feeder current overload. The provision of ancillary services by DERs and FCSs arises as an appealing solution to reduce these adverse effects, enhancing the grid hosting capacity. The control of microgrids is essential for the coordinated implementation of these services. Although microgrid control is widely applied to DERs, few studies address the coordinated control of DERs and FCSs to obtain benefits for the electrical power system. This paper proposes a coordinated and simultaneous control of DERs and FCSs based on the power-based control (PBC) strategy, efficiently exploiting FCSs in a microgrid model previously unaddressed in the literature. The results show that, with the coordinated control of DERs and FCSs, the control of the power flow in a minigrid (MG) is achieved both in moments of high generation and in moments of high load, even with the maximum operation of DERs. This method allows for the maintenance of voltage levels within values considered acceptable by technical standards (above 0.93 pu). The maintenance of voltage levels is derived from reducing the overload on the point of common coupling (PCC) of the minigrid by 28%, performing the peak shaving ancillary service. Furthermore, the method allows for the control of zero power flow in the PCC of the minigrid with the upstream electric grid in periods of high generation, performing the ancillary service of valley filling. The method performs this control without compromising vehicle recharging and power dispatch by DERs.
Full article
(This article belongs to the Special Issue Recent Advances and Challenges in Emerging Power Systems)
►▼
Show Figures
Figure 1
Highly Accessed Articles
Latest Books
E-Mail Alert
News
Topics
Topic in
Applied Sciences, Energies, Fluids, Materials, Processes, Modelling, Inventions
Applied Heat Transfer
Topic Editors: Lioua Kolsi, Walid Hassen, Patrice EstelléDeadline: 31 July 2024
Topic in
Applied Sciences, Electronics, Materials, Applied Nano, Technologies, Inventions, Chips
Advances in Microelectronics and Semiconductor Engineering
Topic Editors: Gerard Ghibaudo, Francis BalestraDeadline: 30 September 2024
Topic in
Applied Sciences, Electronics, Fluids, Micromachines, Processes, Inventions
Micro-Mechatronic Engineering
Topic Editors: Teng Zhou, Antonio F. MiguelDeadline: 31 October 2024
Topic in
Energies, JMSE, Processes, Inventions
Marine Renewable Energy, 2nd Volume
Topic Editors: Eugen Rusu, Kostas Belibassakis, George LavidasDeadline: 30 November 2024
Conferences
Special Issues
Special Issue in
Inventions
Recent Advances in Visible Light Communication and Optical Wireless Information Systems
Guest Editor: Jupeng DingDeadline: 31 May 2024
Special Issue in
Inventions
Innovative Research and Applications of Biofuels and Bioplastics
Guest Editors: Umberto Lucia, Giulia Grisolia, Debora FinoDeadline: 30 June 2024
Special Issue in
Inventions
Innovative Strategy of Protection and Control for the Grid
Guest Editors: Bhaveshkumar R. Bhalja, Om P. MalikDeadline: 31 July 2024
Special Issue in
Inventions
The Development and Optimization of Innovative Systems, Processes, and Materials for the Production, Conversion, and Storage of Energy, 3rd Edition
Guest Editor: Alessandro Dell'EraDeadline: 31 August 2024