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20 pages, 3653 KiB  
Article
Nonlinear Model and Ballistic Impact of Body Aerodynamics for Canard Dual-Spin Aircraft
by Xinxin Zhao, Jinguang Shi, Huajie Ren and Zhongyuan Wang
Aerospace 2025, 12(6), 558; https://doi.org/10.3390/aerospace12060558 - 18 Jun 2025
Viewed by 315
Abstract
Targeting the nonlinear issues of the canard dual-spin aircraft, which relies on the high-speed rotation of the afterbody for flight stability and achieves trajectory correction by adjusting the roll angle of the low-speed rotating forebody to alter aerodynamics, the establishment of an accurate [...] Read more.
Targeting the nonlinear issues of the canard dual-spin aircraft, which relies on the high-speed rotation of the afterbody for flight stability and achieves trajectory correction by adjusting the roll angle of the low-speed rotating forebody to alter aerodynamics, the establishment of an accurate aerodynamic model is crucial for in-depth studies of its ballistic characteristics and design. For this, by taking the effects of canard–body interference, fore/aft body reversal, and other factors into account, an accurate model of the body aerodynamics applicable to large angles of attack is presented. This model theoretically elucidates the intricate relationship between the body aerodynamics and both the flight state and the aerodynamic parameters of the original aircraft. Subsequently, numerical simulations are conducted to analyze the body nonlinear aerodynamic characteristics and their impact on ballistics. The results reveal that all aerodynamic forces and moments acting on the aircraft body, particularly the Magnus force and moment, exhibit strong nonlinearities due to the coupling between the forebody roll angle and the amplitude and phase of the complex angle of attack. Moreover, the established model accurately captures the body aerodynamics and the influence of various disturbance factors, which can significantly alter the controlled angular motions and corrected ballistic calculations. Full article
(This article belongs to the Section Aeronautics)
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22 pages, 1362 KiB  
Review
Bioprotection of the Button Mushroom from Pests and Diseases
by Dejan Marčić, Svetlana Milijašević-Marčić, Tanja Drobnjaković, Jelena Luković, Ljiljana Šantrić, Nikola Grujić and Ivana Potočnik
Agronomy 2025, 15(6), 1323; https://doi.org/10.3390/agronomy15061323 - 28 May 2025
Viewed by 631
Abstract
Commercial production of the button mushroom, Agaricus bisporus (Lange) Imbach, is threatened by various pests and mycopathogenic microorganisms. Sciarid flies (Sciaridae) of the genus Lycoriella are considered as major pests, while major pathogens include the fungi Lecanicillium fungicola (Preuss), Zare and Gams, Hypomyces perniciosus [...] Read more.
Commercial production of the button mushroom, Agaricus bisporus (Lange) Imbach, is threatened by various pests and mycopathogenic microorganisms. Sciarid flies (Sciaridae) of the genus Lycoriella are considered as major pests, while major pathogens include the fungi Lecanicillium fungicola (Preuss), Zare and Gams, Hypomyces perniciosus Magnus, Cladobotryum spp., and Trichoderma aggressivum Samuels & W. Gams, the causative agents of dry bubble, wet bubble, cobweb, and green mold diseases, respectively. Control of mushroom pests and diseases has long relied on synthetic chemical pesticides. Pesticide resistance and various health and environmental issues have created a need for sustainable and eco-friendly alternatives to the use of synthetic chemical pesticides for mushroom pest and disease control. The concept of bioprotection, which involves using biological control agents (BCAs) and biopesticide products, offers a viable alternative. The entomopathogenic nematode Steinernema feltiae (Filipjev) and predatory mite Stratiolaelaps scimitus (Womersley) are the most important invertebrate BCAs, while the bacteria Bacillus thuringiensis Berliner, B. amyloliquefaciens, and B. velezensis stand out as the most widely used microbial BCAs/biopesticides. Azadirachtin- and pyrethrum-based products are the most important biochemical biopesticides. Bioprotection agents require inclusion in the integrated pest and disease management (IPDM) programs in order to achieve their full effectiveness. Full article
(This article belongs to the Section Pest and Disease Management)
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22 pages, 16972 KiB  
Review
The Elias University Hospital Approach: A Visual Guide to Ultrasound-Guided Botulinum Toxin Injection in Spasticity: Part III—Proximal Lower Limb Muscles
by Marius Nicolae Popescu, Claudiu Căpeț, Cristina Beiu and Mihai Berteanu
Toxins 2025, 17(5), 240; https://doi.org/10.3390/toxins17050240 - 13 May 2025
Viewed by 1183
Abstract
Ultrasound-guided botulinum toxin type A (BoNT-A) injections have become an essential tool in the management of lower limb spasticity. Following our previous work, which focused on upper limb muscles, this third part provides a detailed visual guide to the identification and injection of [...] Read more.
Ultrasound-guided botulinum toxin type A (BoNT-A) injections have become an essential tool in the management of lower limb spasticity. Following our previous work, which focused on upper limb muscles, this third part provides a detailed visual guide to the identification and injection of proximal lower limb muscles frequently involved in spastic gait and posture disorders. This guide presents the ultrasound anatomy, clinical relevance, and injection strategies for eleven key muscles: gluteus maximus, piriformis, psoas majorrectus femoris, sartoriusgracilis, adductor longus, adductor magnus, semimembranosus, semitendinosus, and biceps femoris. For each muscle, the Elias University Hospital (EUH) model is applied, highlighting the zones of maximum thickness and motor point density to ensure precise and effective BoNT-A delivery. Enhanced with high-resolution ultrasound images and dynamic scanning techniques, this visual guide supports clinicians in performing safe, targeted injections. It serves as both an educational and practical reference for the ultrasound-guided treatment of spasticity in the proximal lower limb, completing the series and offering a standardized framework for comprehensive BoNT-A management. By promoting accurate toxin delivery, this approach is expected to improve functional mobility, reduce spasticity-related complications, and optimize patient-centered outcomes in rehabilitation settings. Full article
(This article belongs to the Section Bacterial Toxins)
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25 pages, 4423 KiB  
Article
Weed Abundance, Seed Bank in Different Soil Tillage Systems, and Straw Retention
by Sinkevičienė Aušra, Bogužas Vaclovas, Sinkevičius Alfredas, Steponavičienė Vaida, Anicetas Lenkis and Kimbirauskienė Rasa
Agronomy 2025, 15(5), 1105; https://doi.org/10.3390/agronomy15051105 - 30 Apr 2025
Cited by 1 | Viewed by 488
Abstract
Comprehensive studies are needed to investigate the diversity, abundance, and seed bank of weeds in winter wheat, spring barley, and spring oilseed rape crops due to a lack of experimental studies. Tillage has a long-term impact on agroecosystems. Since 1999, a long-term field [...] Read more.
Comprehensive studies are needed to investigate the diversity, abundance, and seed bank of weeds in winter wheat, spring barley, and spring oilseed rape crops due to a lack of experimental studies. Tillage has a long-term impact on agroecosystems. Since 1999, a long-term field experiment has been conducted at the Experimental Station of Vytautas Magnus University. The soil of the experimental site is classified as Epieutric Endocalcaric Planosol (Endoclayic, Episiltic, Aric, Drainic, Endoraptic, Uterquic), according to the World Reference Base. Treatments were arranged using a split-plot design. According to the factorial field experiment, the straw was removed from one part of the experimental field, and on the other part of the field, the straw was chopped and spread at harvesting (factor A). Six tillage systems, conventional (deep) and shallow plowing, shallow loosening, shallow rotovation, catch cropping and rotovation, and no tillage, were used as a subplot (factor B). The current study results show that the number of annual, perennial, and total weeds and the dry matter biomass decreased in shallow-plowed plots compared to deep-plowed plots. Different applied tillage treatments had different effects on perennial weeds. In the upper (0–10 cm) soil layer studied, the number of annual, perennial, and total weed seeds decreased in the fields where the straw was chopped and spread compared to the fields where the straw was removed. In the deeper soil layer (10–25 cm), no tillage with cover crops and direct seeding without cover crops reduced the number of annual and perennial weed seeds compared to deep tillage. The aim of this experiment was to investigate the effects of long-term tillage of different intensities and straw retention systems on weeds in crop fields. The results were obtained in 2019 and 2021 (winter wheat, spring barley, spring oilseed rape). Full article
(This article belongs to the Section Weed Science and Weed Management)
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25 pages, 15432 KiB  
Article
Aerodynamic Characteristics and Dynamic Stability of Coning Motion of Spinning Finned Projectile in Supersonic Conditions
by Jintao Yin, Shengju Jiang, Yaowei Hu, Jiawei Zhang, Haochun Miao and Juanmian Lei
Aerospace 2025, 12(3), 225; https://doi.org/10.3390/aerospace12030225 - 10 Mar 2025
Cited by 1 | Viewed by 1053
Abstract
For a spinning projectile, coning motion induced by disturbances during flight can have a unique impact on the lateral force and yawing moment, which may further affect flight stability and maneuverability. The flow over a coupled spinning–coning projectile and a spinning projectile was [...] Read more.
For a spinning projectile, coning motion induced by disturbances during flight can have a unique impact on the lateral force and yawing moment, which may further affect flight stability and maneuverability. The flow over a coupled spinning–coning projectile and a spinning projectile was numerically simulated by solving the unsteady Reynolds-averaged Navier–Stokes (URANS) equation with an implicit dual-time stepping method and a spinning–coning coupled motion model established through a dynamic mesh technique. The variation in transient and time-averaged aerodynamic characteristics with the angle of attack (AoA), dimensionless spin rate, and dimensionless cone rate was analyzed, and the specific effect of coning motion on the lateral force and yawing moment was revealed. Based on these findings, the yawing moment term in traditional angular motion theory was modified, and the flight response to the initial disturbance was discussed. The results indicate that the time-averaged lateral force and yawing moment of the spinning–coning coupled projectile are multiplied compared with those of the spinning projectile and vary linearly with the dimensionless spin rate and cone rate. The main factors affecting the lateral force are the coning motion-induced effective angle of sideslip (AoS), asymmetric expansion waves, and asymmetric vortices. The much larger yawing moment induced by spinning–coning coupled motion can more easily cause AoA divergence and flight instability. Full article
(This article belongs to the Section Aeronautics)
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10 pages, 207 KiB  
Review
Deep Brain Stimulation and Brain–Spine Interface for Functional Restoration in Spinal Cord Injury
by Barnabas T. Shiferaw, Max Y. Jin, Milan Patel, Lukas J. Henjum and Alaa Abd-Elsayed
Biomedicines 2025, 13(3), 631; https://doi.org/10.3390/biomedicines13030631 - 5 Mar 2025
Viewed by 1598
Abstract
Background/Objectives: Spinal cord injury (SCI) presents significant challenges in restoring motor function, with limited therapeutic options available. Recent advancements in neuromodulation technologies, such as brain-spine interface (BSI), epidural electrical stimulation (EES), and deep brain stimulation (DBS), offer promising solutions. This review article [...] Read more.
Background/Objectives: Spinal cord injury (SCI) presents significant challenges in restoring motor function, with limited therapeutic options available. Recent advancements in neuromodulation technologies, such as brain-spine interface (BSI), epidural electrical stimulation (EES), and deep brain stimulation (DBS), offer promising solutions. This review article explores the integration of these approaches, focusing on their potential to restore function in SCI patients. Findings: DBS has shown efficacy in SCI treatment with several stimulation sites identified, including the nucleus raphe magnus (NRM) and periaqueductal gray (PAG). However, transitioning from animal to human studies highlights challenges, including the technical risks of targeting the NRM in humans instead of rodent models. Additionally, several other regions have shown potential for motor rehabilitation, including the midbrain locomotor region (MLR) pathways, cuneiform nucleus (CnF), pedunculopontine nucleus (PPN), and lateral hypothalamic. DBS with EES further supports motor recovery in SCI; however, this approach requires high-DBS amplitude, serotonergic pharmacotherapy, and cortical activity decoding to attenuate stress-associated locomotion. BSI combined with EES has recently emerged as a promising novel therapy. Although human studies are limited, animal models have provided evidence supporting its potential. Despite these advancements, the effectiveness of DBS and combined systems remains limited in cases of complete central denervation. Conclusions: The integration and combination of DBS, BSI, and EES represent a transformational approach to treating and restoring function in patients with SCI. While further research is needed to optimize these strategies, these advancements hold immense potential for improving the quality of life in SCI patients and advancing the field of neuromodulation. Full article
(This article belongs to the Special Issue Emerging Trends in Brain Stimulation)
11 pages, 6934 KiB  
Case Report
Calcifications of the Knee’s Medial Compartment: A Case Report and Literature Review on the Adductor Magnus Tendon as an Uncommon Location and the Role of Ultrasound-Guided Lavage
by Elena Jiménez-Herranz, Joao Vitor de Castro Fernandes, Juan José Ramos-Álvarez, Federico Del-Castillo-Díez, André Pedrinelli, Sofia Alvariza-Ciancio, Cristian Solís-Mencía and Federico Del-Castillo-González
Diagnostics 2025, 15(5), 534; https://doi.org/10.3390/diagnostics15050534 - 22 Feb 2025
Viewed by 1123
Abstract
Background: This paper examines the diverse etiologies of medial knee pain, emphasizing the prevalence of calcification-related pathologies, such as Pellegrini–Stieda Syndrome (PSS), particularly in the medial collateral ligament (MCL) and adjacent structures. Furthermore, we present a case of calcification of the distal adductor [...] Read more.
Background: This paper examines the diverse etiologies of medial knee pain, emphasizing the prevalence of calcification-related pathologies, such as Pellegrini–Stieda Syndrome (PSS), particularly in the medial collateral ligament (MCL) and adjacent structures. Furthermore, we present a case of calcification of the distal adductor magnus tendon (DAMT) insertion into the femoral condyle of the knee and describe its treatment using ultrasound-guided percutaneous lavage (UGPL). A narrative review was conducted based on a single case; it underscores the importance of accurate diagnosis using magnetic resonance imaging (MRI) to differentiate between various calcific conditions, guiding appropriate treatment strategies. Case Presentation: A 70-year-old patient presenting with severe medial knee pain, with a duration of 4 days, and functional impotence underwent X-ray, ultrasound, and magnetic resonance imaging (MRI) examinations, revealing calcification in the DAMT. Treatment consisted of UGPL. The patient’s pain level was assessed using the visual analog scale (VAS) initially and after 30 days of treatment. Upon initial assessment, the patient reported a VAS score of 9 out of 10. After 30 days of completing the treatment, the symptoms ceased. Follow-up imaging (X-ray, ultrasound, and MRI) showed only very tiny fragments of calcification remaining. Conclusions: UGPL is an effective technique for treating calcific tendinopathy of the DAMT insertion into the medial femoral condyle of the knee, offering significant pain relief and functional improvement. This case highlights the importance of considering this rare condition in the differential diagnosis of medial knee pain. Full article
(This article belongs to the Section Medical Imaging and Theranostics)
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16 pages, 1919 KiB  
Article
Soil Water Capacity and Pore Size Distribution in Different Soil Tillage Systems in the Spring Barley Crop
by Aušra Sinkevičienė, Inesa Sinkevičiūtė, Karolina Jackevičienė, Kęstutis Romaneckas, Jovita Balandaitė, Augustas Sederevičius and Rasa Kimbirauskienė
Land 2024, 13(12), 2198; https://doi.org/10.3390/land13122198 - 16 Dec 2024
Viewed by 762
Abstract
Barley is an important cereal crop with versatile uses: barley grains are part of the human diet and are also used for animal feed, while the potential to use barley for ethanol production provides this grain with a promising bioenergy potential. As scientific [...] Read more.
Barley is an important cereal crop with versatile uses: barley grains are part of the human diet and are also used for animal feed, while the potential to use barley for ethanol production provides this grain with a promising bioenergy potential. As scientific research in the field of bioenergy progresses, barley may play an even greater role in meeting the world’s future energy needs. The challenge facing today’s barley growers, and one that will undoubtedly be addressed by future generations of grain farmers, is how to grow higher yields with lower costs while minimizing damage to the soil. One way to achieve this is by using simplified tillage methods, thereby avoiding soil compaction, structural degradation, and erosion. Moreover, studies have shown that when soil is cultivated using simplified methods, crop yields may actually increase. Our research was conducted in a long-term stationary field experiment, which was located at the Vytautas Magnus University Agriculture Academy Experimental Station. The aim of the investigation was to determine the effect of conservation tillage and deep plowing systems on soil water capacity and pore size distribution in spring barley cultivation. Comparing simplified tillage systems with deep plowing (DP), it can be concluded that the no-tillage (NT) technology most significantly improved the studied indicators, while the deep plowing (DP) technology exhibited the poorest results. Full article
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17 pages, 834 KiB  
Article
The Influence of Maceration on the Biodiversity of Yeasts in the Early Winemaking Stages of White Wine from the Slovak Tokay Wine Region
by Ivana Regecová, Jana Výrostková, Boris Semjon, Viera Lovayová, Pavlina Jevinová, Zuzana Megyesy Eftimová, Martin Bartkovský, Monika Pipová and Slavomír Marcinčák
Foods 2024, 13(23), 3792; https://doi.org/10.3390/foods13233792 - 26 Nov 2024
Cited by 1 | Viewed by 901
Abstract
This study investigates the effect of maceration and different winemaking techniques on the species diversity of yeasts in white wines from the Slovak Tokay wine region, known for its traditional white wine production. Lipovina grape variety samples were divided into three groups: control [...] Read more.
This study investigates the effect of maceration and different winemaking techniques on the species diversity of yeasts in white wines from the Slovak Tokay wine region, known for its traditional white wine production. Lipovina grape variety samples were divided into three groups: control (C), macerated (M) and macerated with the addition of a yeast culture (MY). During the entire fermentation process, quantitative and qualitative microbiological analyses of the raw material and must samples were carried out, which resulted in the identification of 60 yeast isolates via the API 20 C AUX biochemical test and MALDI-TOF MS. Identification was further verified via Sanger sequencing of PCR amplicons, which confirmed the presence of less common wild yeasts in Tokay wine must samples, including Aureobasidium pullulans, Cryptococcus magnus, Torulaspora delbrueckii and Rhodotorula sp. The highest species diversity was observed in the macerated group. These findings indicate that the quality and distinctiveness of Slovak Tokay wines can be increased by careful management of the maceration process during winemaking procedures. Full article
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31 pages, 5369 KiB  
Article
Evaluation of the Effects of Body Forces and Diffusion Mechanisms on Droplet Separation in a Two-Phase Annular–Mist Flow
by Oktawia Dolna
Appl. Sci. 2024, 14(23), 10793; https://doi.org/10.3390/app142310793 - 21 Nov 2024
Viewed by 763
Abstract
For decades, studies have been conducted on the efficiency of gas purification processes with wet scrubbers, including the Venturi scrubbers, and this is the most commonly addressed issue in the field literature. The Venturi scrubber consists of a Venturi nozzle and a cyclone. [...] Read more.
For decades, studies have been conducted on the efficiency of gas purification processes with wet scrubbers, including the Venturi scrubbers, and this is the most commonly addressed issue in the field literature. The Venturi scrubber consists of a Venturi nozzle and a cyclone. The article addresses the empirical and analytical studies on the annular–mist flow regime that exists in the throat of the Venturi nozzle with a square cross-section. The uniform distribution of droplets over the cross-section area of the Venturi’s throat strongly correlates with the efficiency of the gas cleaning process using Venturi scrubbers. Due to the above, studies on the physics of the phenomena that affect the quantity of small droplets present in the core of the flow are highly justified. The influence of body forces and diffusive mechanisms impacting the number of droplets in the core flow were investigated to tackle the problem in question. Consequently, the fractions of droplets susceptible to turbulent or inertial–turbulent diffusion mechanisms can now be predicted using the outcomes of the research carried out. The droplets were divided into three fractions that differed by their sizes as follows: airborne droplets I confirm thar italic can be removed in all cases. (dd 10 µm), medium-sized droplets (dd 20 µm), and largest droplets (dd = (50–150) µm). The estimation of diffusion coefficients εd,M,εd,ref and stopping distances sM,sref of all fractions of droplets was carried out with the inclusion εd,M,sM and exclusion εd,ref,sref of the Magnus lift force M in equations of both the droplet’s stopping distance and its diffusion coefficient. The outcomes revealed that the inclusion of the M force translates significantly to the growth in values of εd,M,sM compared to εd,ref,sref. Hence, it was concluded that the M force impacts the increase in the speed of the diffusion of the droplets with dd 16.45 µm, which is favorable. Hence, the inertial–turbulent diffusion of larger droplets and the turbulent diffusion of medium ones seem to be supported by the M force. The local velocity gradient, which varied within the region of the flow’s hydraulic stabilization also impacted the mass content of droplets with diameter dd 10 µm in the core of the flow. As the flow development progressed, the number of droplets measured at n = 5 Hz varied nonlinearly up to the point where the boundary layer thickness reached the channel radius. The quantity of small droplets in the main flow was significantly influenced by turbulence intensity (Tu). The desired high number of small droplets in the core of the flow (mist flow) was estimated empirically, and it was achieved when gas flows at high speed and has a mean value of Tu. The former benefits the efficiency of gas purification. Investigations on the effects of body forces of inertia of the continuous phase on the separation of droplets with diameters of a few microns and sub-microns from the flow were performed by employing two channel elbows, namely e4 and e1. The curved channels were subsequently mounted at the end of the straight channel (SCh2). The curvature angle (α) of the e4 and e1 equaled 90 °C and 30 °C, respectively. The number of droplets existing in the mist flow was higher in value, as desired, when the e4 was used, unlike e1. Two-dimensional flow fields of the mist have been obtained using the Particle Imaging Velocimetry (PIV) technique and analyzed further. Topas LAP 332 Aerosol Spectrometer was used for the determination of droplet (dd 40 µm) size distribution (DSD) and particle concentrations, while the Droplet Size Analyzer D Kamika Instruments (DSA) was exploited to ascertain DSD of droplets with diameter dd>40 µm. Full article
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19 pages, 3195 KiB  
Article
Development of an Optimized Non-Linear Model for Precise Dew Point Estimation in Variable Environmental Conditions
by José Antonio Hernandez-Torres, Juan P. Torreglosa, Reyes Sanchez-Herrera, Aldo Bischi and Andrea Baccioli
Appl. Sci. 2024, 14(22), 10508; https://doi.org/10.3390/app142210508 - 14 Nov 2024
Viewed by 1278
Abstract
Accurate dew point estimation is crucial for measuring water condensation in various fields such as environmental studies, agronomy, or water harvesting, among others. Despite the numerous models and equations developed over time, including empirical and machine learning approaches, they often involve trade-offs between [...] Read more.
Accurate dew point estimation is crucial for measuring water condensation in various fields such as environmental studies, agronomy, or water harvesting, among others. Despite the numerous models and equations developed over time, including empirical and machine learning approaches, they often involve trade-offs between accuracy, simplicity, and computational cost. A major limitation of the current approaches is the lack of balance among these three factors, limiting their practical applications under diverse conditions. This research addresses these key challenges by developing a new, streamlined equation for dew point estimation. Using the Magnus–Tetens equation, deemed as the most reliable equation, as a benchmark, and by applying a process of non-linear regression fitting and parametric optimization, a new equation was derived. The results demonstrate high accuracy with a streamlined implementation, validated through extensive data and computational simulations. This study highlights the importance of accurate dew point modeling, especially under variable environmental conditions, provides a reliable solution to existing limitations, paving the way for enhanced efficiency in related processes and research endeavors, and offers researchers and practitioners a practical tool for more effective modeling of water condensation phenomena. Full article
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25 pages, 13851 KiB  
Article
The Generation Mechanism of the Side Force and Yawing Moment of a Rotating Missile with Wrap-Around Fins
by Zheng Yong, Juanmian Lei and Jintao Yin
Aerospace 2024, 11(9), 765; https://doi.org/10.3390/aerospace11090765 - 18 Sep 2024
Cited by 1 | Viewed by 1729
Abstract
The rotation of a missile generates a side force perpendicular to the plane containing the attack angle and produces a yawing moment that tilts the body out of the plane, significantly affecting the flight stability of rotating missiles. The non-planar asymmetry of the [...] Read more.
The rotation of a missile generates a side force perpendicular to the plane containing the attack angle and produces a yawing moment that tilts the body out of the plane, significantly affecting the flight stability of rotating missiles. The non-planar asymmetry of the wrap-around-fin rotating missile determines its more complex rotational effects. This study utilizes the dual time-step method to solve the unsteady Navier–Stokes equations, investigating the characteristics of the side force and yawing moment of the wrap-around-fin rotating missile under supersonic conditions and uncovering the mechanism behind the generation of the side force and yawing moment. The results reveal that the side force and yawing moment of the wrap-around-fin missile are composed of static values and induced values from rotation. The static side force and yawing moment of the wrap-around-fin missile are not zero, while those of the flat-plate-fin missile are zero. This difference is primarily caused by the non-axisymmetric nature of the wrap-around fin, resulting in the static side force and yawing moment of the wrap-around-fin missile being 40% greater than those of the flat-plate-fin missile. The rotation of the missile increases the effective angle of attack on the convex surface of the fin and decreases it on the concave surface, leading to an imbalance in the pressure changes on the windward and leeward sides. This is the main reason for the generation of the induced side force and yawing moment due to rotation. The induced values from rotation vary linearly with the rotation rate, and their magnitudes can be several times those of the static values. Full article
(This article belongs to the Section Aeronautics)
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18 pages, 7719 KiB  
Article
Numerical Simulation to Investigate the Effect of Adding a Fixed Blade to a Magnus Wind Turbine
by Ainura Dyusembaeva, Nazgul Tanasheva, Ardak Tussypbayeva, Asem Bakhtybekova, Zhibek Kutumova, Sholpan Kyzdarbekova and Almat Mukhamedrakhim
Energies 2024, 17(16), 4054; https://doi.org/10.3390/en17164054 - 15 Aug 2024
Cited by 2 | Viewed by 1229
Abstract
The investigation of aerodynamics and the establishment of flow patterns around finite-length cylinders with various end shapes in a free, boundless air flow with longitudinal and transverse flow over a wide range of geometric and regime parameters is sketchy and does not have [...] Read more.
The investigation of aerodynamics and the establishment of flow patterns around finite-length cylinders with various end shapes in a free, boundless air flow with longitudinal and transverse flow over a wide range of geometric and regime parameters is sketchy and does not have a wide range of geometric and regime parameters. This, in turn, affects the entire aerodynamics of the streamlined body. This paper considers the numerical simulation of a wind turbine made of combined blades. CFD (computational fluid dynamics) methods based on the realisable k-ε turbulence model were used in the study. The results on the influence of the position of the fixed blade on the angle of inclination are obtained (0°, 15°, 30°, 45°, and 60°). The authors found that the pressure of a fixed blade at an optimal angle increases the power coefficient Cp by 35–40%. The dependence of the Cp power coefficient on the rotational speed (speed coefficient) for a three-bladed wind turbine was also established, and it was determined that the maximum value of Cp = 0.28 at Z = 4.9. Based on the results obtained, it was determined that the wind turbine has a maximum power coefficient at an angle of inclination of 0 degrees. Full article
(This article belongs to the Section A3: Wind, Wave and Tidal Energy)
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15 pages, 1022 KiB  
Article
Long-Term Effect of Tillage Systems on Planosol Physical Properties, CO2 Emissions and Spring Barley Productivity
by Aušra Sinkevičienė, Kęstutis Romaneckas, Karolina Jackevičienė, Toma Petrikaitė, Jovita Balandaitė and Rasa Kimbirauskienė
Land 2024, 13(8), 1289; https://doi.org/10.3390/land13081289 - 15 Aug 2024
Cited by 1 | Viewed by 1243
Abstract
As the population grows, more food is needed to keep the food supply chain running smoothly. For many years, intensive farming systems have been used to meet this need. Currently, due to intense climate change and other global natural problems, there is a [...] Read more.
As the population grows, more food is needed to keep the food supply chain running smoothly. For many years, intensive farming systems have been used to meet this need. Currently, due to intense climate change and other global natural problems, there is a shift towards sustainable use of natural resources and simplified methods of tillage. Soil tillage intensity influences the distribution of nutrients, and soil’s physical and mechanical properties, as well as gas flows. The impact of reduced tillage on these indices in spring barley cultivation is still insufficient and requires more analysis on a global scale. This study was carried out at Vytautas Magnus University, Agriculture Academy (Lithuania) in 2022–2023. The aim of the investigation was to determine the effect of the tillage systems on the soil temperature, moisture content, CO2 respiration and concentration in spring barley cultivation. Based on a long-term tillage experiment, five tillage systems were tested: deep and shallow moldboard ploughing, deep cultivation-chiseling, shallow cultivation-chiseling, and no tillage Shallow plowing technology has been found to better conserve soil moisture and maintain higher temperatures in most cases. During almost the entire study period, the spring barley crop with deep cultivation had lower moisture content and lower soil temperature. Shallow cultivation fields in most cases increased CO2 emissions and CO2 concentration. When applying direct sowing to the uncultivated soil (10–20 cm), the concentration of CO2 decreased from 0.01 to 0.148 percent. pcs. The results show that in direct sowing fields, most cases had a positive effect on crop density. Direct sowing fields resulted in significantly lower, from 7.9 to 26.5%, grain yields of spring barley in the years studied. Full article
(This article belongs to the Special Issue Tillage Methods on Soil Properties and Crop Growth)
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10 pages, 836 KiB  
Article
Effect of Burned Multi-Crop Ashes on Faba Bean-Development Parameters
by Rita Petlickaitė, Kęstutis Romaneckas, Aušra Sinkevičienė, Marius Praspaliauskas and Algirdas Jasinskas
Plants 2024, 13(16), 2182; https://doi.org/10.3390/plants13162182 - 7 Aug 2024
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Abstract
The use of burned plant biomass ashes could help not only with respect to utilizing combustion residues, but also with respect to optimizing the nutrition of cultivated agricultural plants without harming the environment. With this aim, a pot experiment of the effects of [...] Read more.
The use of burned plant biomass ashes could help not only with respect to utilizing combustion residues, but also with respect to optimizing the nutrition of cultivated agricultural plants without harming the environment. With this aim, a pot experiment of the effects of multi-crop biomass ash on faba bean seedlings was carried out in the Academy of Agriculture of the Vytautas Magnus University (VMU). Four ash fertilization rates were tested: 1. unfertilized (N0, comparative-control treatment); 2. fertilized at a low rate (N1, 200 kg ha−1); 3. fertilized at an average rate (N2, 1000 kg ha−1); 4. fertilized at a high rate (N3, 2000 kg ha−1). Final observations showed that ash fertilization significantly increases the height of faba bean sprouts by 21–38%, the length of the roots by 10–20% and the chlorophyll concentration in the leaves by 17%. The average green biomass of faba bean sprouts consistently increased with increasing fertilization rate, from 56% to 209%. Dried biomass increased by 160–220%. With increasing ash fertilization rate, the percentage of dry matter in the roots decreased by 10–50%. We recommend fertilizing faba bean with medium (1000 kg ha−1) and high (2000 kg ha−1) ash rates, as these rates led to the largest plants with the highest productivity potential. Full article
(This article belongs to the Section Crop Physiology and Crop Production)
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