Pub Date : 2020-06-19DOI: 10.15587/1729-4061.2020.204251
A. Petrov, A. Paliy, M. Pavliuchenkov, H. Tsyhanenko, Nadiia Khobot, Ivan Vysochin, O. Yurchenko, Oleksii Ovcharenko, D. Sopov, A. Paliy
An algorithm has been developed to select rigid stops in steel-concrete beams under the action of distributed load. Concrete is connected rigidly to a steel sheet in order to perform the joint operation of the concrete and steel sheet. Such a connection in the beam is provided by rigid stops that prevent shifting efforts in the concrete and steel contact area. The efforts are determined through the turning angles between the two adjacent sections of the beam. A graph-analytical method for determining movements is used to determine the turning angles. In determining the deformations of a steel-concrete beam, the calculation is based on the reduced rigidities of cross-sections. The purpose of this study is to optimize the structure of a steel-concrete beam by selecting the rational number and arrangement of rigid stops. This optimization would allow a more rational utilization of the structure's material ‒ concrete and steel. That would reduce the cost of operations and the quantity of materials required in the production, installation, and operation of the considered structures. An earlier proposed algorithm for the selection of rigid stops in steel-concrete beams under the action of a concentrated force has been expanded for the case of an evenly distributed load. When selecting the number of rigid stops, it is assumed that the magnitude of the distributed load acting on a beam, the mechanical characteristics of materials (steel and concrete), as well as the span of the beam and the size of its cross-section, are kNown. In contrast to the beams with a concentrated force in the middle, where the forces abide by a linear law, in the beams with an evenly distributed load the efforts in a steel strip change in line with a square parabola. Therefore, while the same step has been obtained for stops, it is not possible to achieve a situation at which efforts in all stops have the same value
{"title":"Construction of an Algorithm for the Selection of Rigid Stops in Steel-Concrete Beams Under the Action of a Distributed Load","authors":"A. Petrov, A. Paliy, M. Pavliuchenkov, H. Tsyhanenko, Nadiia Khobot, Ivan Vysochin, O. Yurchenko, Oleksii Ovcharenko, D. Sopov, A. Paliy","doi":"10.15587/1729-4061.2020.204251","DOIUrl":"https://doi.org/10.15587/1729-4061.2020.204251","url":null,"abstract":"An algorithm has been developed to select rigid stops in steel-concrete beams under the action of distributed load. Concrete is connected rigidly to a steel sheet in order to perform the joint operation of the concrete and steel sheet. Such a connection in the beam is provided by rigid stops that prevent shifting efforts in the concrete and steel contact area. The efforts are determined through the turning angles between the two adjacent sections of the beam. A graph-analytical method for determining movements is used to determine the turning angles. In determining the deformations of a steel-concrete beam, the calculation is based on the reduced rigidities of cross-sections. The purpose of this study is to optimize the structure of a steel-concrete beam by selecting the rational number and arrangement of rigid stops. This optimization would allow a more rational utilization of the structure's material ‒ concrete and steel. That would reduce the cost of operations and the quantity of materials required in the production, installation, and operation of the considered structures. An earlier proposed algorithm for the selection of rigid stops in steel-concrete beams under the action of a concentrated force has been expanded for the case of an evenly distributed load. When selecting the number of rigid stops, it is assumed that the magnitude of the distributed load acting on a beam, the mechanical characteristics of materials (steel and concrete), as well as the span of the beam and the size of its cross-section, are kNown. In contrast to the beams with a concentrated force in the middle, where the forces abide by a linear law, in the beams with an evenly distributed load the efforts in a steel strip change in line with a square parabola. Therefore, while the same step has been obtained for stops, it is not possible to achieve a situation at which efforts in all stops have the same value","PeriodicalId":18300,"journal":{"name":"MatSciRN: Other Materials Processing & Manufacturing (Topic)","volume":"44 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79492754","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Vurat, Sukran Seker, Özge Lalegül-Ülker, Mahmut Parmaksiz, A. E. Elçin, Y. M. Elçin
While periodontal (PD) disease is among principal causes of tooth loss worldwide, regulation of concomitant soft and mineralized PD tissues, and PD pathogenesis have not been completely clarified yet. Besides, relevant pre-clinical models and in vitro platforms have limitations in accurately simulating human physiology. A periodontium-on-a-chip, emulating PD ligament-alveolar bone (PDL-AB) biointerface has not been developed to date. In this study, we have harnessed three-dimensional bioprinting (3DP) technology for developing such a system for the first time. PDL was modelled by using gelatin methacryloyl (Gel-MA) bioink for bioprinting human periodontal ligament fibroblasts. On the side, AB was modelled by using a composite bioink comprised of Gel-MA and hydroxyapatite-magnetic iron oxide nanoparticles (Gel-MA/HAp-MNPs) for bioprinting human osteoblasts. MNPs were incorporated to bring magnetic properties to the mineralized layer for use in prospective orthodontic mechanotransduction studies. The 3DP parameters of the composite microtissue were optimized; the physical, chemical, rheological, mechanical, and thermal properties of the constructs were assessed. Finally, preliminary evaluation of the model drug tetracycline interactions was performed. Thus, the effects of the tetracyclines on PDL-AB have clinical significance for treating PD diseases. This periodontium-on-a-chip model represents a reproducible in vitro platform for studying processes of healthy and diseased human PDL.
{"title":"3D-Bioprinted Human Periodontal/Osteoblastic Microfluidic Tissue-on-A-Chip System and Evaluation of Model Drug Interactions","authors":"M. Vurat, Sukran Seker, Özge Lalegül-Ülker, Mahmut Parmaksiz, A. E. Elçin, Y. M. Elçin","doi":"10.2139/ssrn.3622631","DOIUrl":"https://doi.org/10.2139/ssrn.3622631","url":null,"abstract":"While periodontal (PD) disease is among principal causes of tooth loss worldwide, regulation of concomitant soft and mineralized PD tissues, and PD pathogenesis have not been completely clarified yet. Besides, relevant pre-clinical models and in vitro platforms have limitations in accurately simulating human physiology. A periodontium-on-a-chip, emulating PD ligament-alveolar bone (PDL-AB) biointerface has not been developed to date. In this study, we have harnessed three-dimensional bioprinting (3DP) technology for developing such a system for the first time. PDL was modelled by using gelatin methacryloyl (Gel-MA) bioink for bioprinting human periodontal ligament fibroblasts. On the side, AB was modelled by using a composite bioink comprised of Gel-MA and hydroxyapatite-magnetic iron oxide nanoparticles (Gel-MA/HAp-MNPs) for bioprinting human osteoblasts. MNPs were incorporated to bring magnetic properties to the mineralized layer for use in prospective orthodontic mechanotransduction studies. The 3DP parameters of the composite microtissue were optimized; the physical, chemical, rheological, mechanical, and thermal properties of the constructs were assessed. Finally, preliminary evaluation of the model drug tetracycline interactions was performed. Thus, the effects of the tetracyclines on PDL-AB have clinical significance for treating PD diseases. This periodontium-on-a-chip model represents a reproducible in vitro platform for studying processes of healthy and diseased human PDL.","PeriodicalId":18300,"journal":{"name":"MatSciRN: Other Materials Processing & Manufacturing (Topic)","volume":"60 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91234063","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-06-19DOI: 10.15587/1729-4061.2020.203551
O. Slavinska, A. Bubela, Oleksandr Chechuha, L. Bondarenko
To date, there are virtually no experimental studies of drainage structures. The object of the presented study is a road structure with transverse shallow drainage arranged in wet sections of roads. In order to determine the drainage intensity of the drainage structure, an experiment was performed on a special installation for modeling the road structure depending on the properties of filler materials. Parameters of the installation make it possible to arrange a structure that corresponds to real conditions, that is, the parameters of a road of category III and study the processes of formation of the filtration flow in the drainage trench which is impossible with real objects. The laboratory installation was used to study operating conditions of drainage structures: a layer of crushed stone of 20–40 mm fraction and two types of transverse shallow drains with different filler materials in the trench. In the process of a series of experimental studies, the volume of water drained from the trench and drainage time was measured. According to the study results, based on the methods of mathematical statistics, unified equations of the correlation-regression model concerning the mode of operation of the drainage structure were constructed depending on initial soil moisture in the roadbed. According to the results of experimental studies, one of the main indicators of work of shallow drainage structures which depends on the properties of materials of trenches fillers, that is, the drainage intensity was determined. It was found that in contrast to the structure with a PVC pipe filled with coarse sand, the drainage structure with a crushed stone core in the trench worked in one mode of the formed flow. The work of the structure with the pipe is divided into short-term and long-term modes depending on the drainage intensity. The obtained regression dependences enable forecasting of the amount of water drained by the proposed drainage structures in a certain period for field conditions
{"title":"The Intensity of Water Removal From Shallow Drainage Systems Considering the Properties of Filler Materials","authors":"O. Slavinska, A. Bubela, Oleksandr Chechuha, L. Bondarenko","doi":"10.15587/1729-4061.2020.203551","DOIUrl":"https://doi.org/10.15587/1729-4061.2020.203551","url":null,"abstract":"To date, there are virtually no experimental studies of drainage structures. The object of the presented study is a road structure with transverse shallow drainage arranged in wet sections of roads. In order to determine the drainage intensity of the drainage structure, an experiment was performed on a special installation for modeling the road structure depending on the properties of filler materials. Parameters of the installation make it possible to arrange a structure that corresponds to real conditions, that is, the parameters of a road of category III and study the processes of formation of the filtration flow in the drainage trench which is impossible with real objects. The laboratory installation was used to study operating conditions of drainage structures: a layer of crushed stone of 20–40 mm fraction and two types of transverse shallow drains with different filler materials in the trench. In the process of a series of experimental studies, the volume of water drained from the trench and drainage time was measured. According to the study results, based on the methods of mathematical statistics, unified equations of the correlation-regression model concerning the mode of operation of the drainage structure were constructed depending on initial soil moisture in the roadbed. According to the results of experimental studies, one of the main indicators of work of shallow drainage structures which depends on the properties of materials of trenches fillers, that is, the drainage intensity was determined. It was found that in contrast to the structure with a PVC pipe filled with coarse sand, the drainage structure with a crushed stone core in the trench worked in one mode of the formed flow. The work of the structure with the pipe is divided into short-term and long-term modes depending on the drainage intensity. The obtained regression dependences enable forecasting of the amount of water drained by the proposed drainage structures in a certain period for field conditions","PeriodicalId":18300,"journal":{"name":"MatSciRN: Other Materials Processing & Manufacturing (Topic)","volume":"5 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81453466","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-06-19DOI: 10.15587/1729-4061.2020.204780
Volodymyr Shmyrov, V. Merkulov, V. Loginov
In order to create new competitive advantages for the medium-haul aircraft An-148 and An-158, the application of the D-436-148FM engine for these aircraft has been considered. This would expand the operational range of aircraft flights, reduce noise on the ground, and harmful emissions from the engine. A distinctive feature is the achieved thrust of the engine D-436-148FM undera maximum emergency mode, 19.4 % higher than the thrust of the engine D-436-148D. That was made possible by optimizing the fan, improving the combustion chamber, and turbine cascade. The required amount of bench and flight tests has been performed. The engine certification is currently being completed. Specialists at the Antonov State Enterprise and Ivchenko-Progress State Enterprise studied the issue of installing the D-436-148FM engine on the An-148 and An-158 aircraft family. No changes to the design of the engine and aircraft are required. The engine is mounted on the same pylons without changes to the nacelle and engine bonnets. Energy-dependent systems associated with the engine have been investigated. There is no need for the fundamental changes in related systems for the engine’s operational modes according to the Aircraft Flight Manual. An engineering analysis of the comparison of flight-technical and flight-landing characteristics of the An-158 aircraft equipped with the engines D-436-148D and D-436-148FM has been performed. The data were obtained from the flight tests of the An-158 certified aircraft, taking into consideration the wind tunnel studies, flight tests of the An-178 aircraft, data from the An-158 Flight Manual, and the altitude and speed performance of the D-436-148D and D-436-148FM engines. The altitude and speed characteristics of the D-436-148FM engine, which have been calculated, were confirmed by the flight tests of the An-178 aircraft. A feasibility study of engine replacement has been carried out, based on the comparison of the technical and economic characteristics of the An-158 aircraft equipped with the D-436-148D engine and D-436-148FM operated in various atmospheric conditions. The principle of creating a family of aircraft of transport category of different configurations and purposes, based on a single engine, has been proposed
{"title":"Principle of Modernization of the Aircraft An-148, An-158, and An-178 for Improving Their Fuel Efficiency and Increasing Competitiveness","authors":"Volodymyr Shmyrov, V. Merkulov, V. Loginov","doi":"10.15587/1729-4061.2020.204780","DOIUrl":"https://doi.org/10.15587/1729-4061.2020.204780","url":null,"abstract":"In order to create new competitive advantages for the medium-haul aircraft An-148 and An-158, the application of the D-436-148FM engine for these aircraft has been considered. This would expand the operational range of aircraft flights, reduce noise on the ground, and harmful emissions from the engine. A distinctive feature is the achieved thrust of the engine D-436-148FM undera maximum emergency mode, 19.4 % higher than the thrust of the engine D-436-148D. That was made possible by optimizing the fan, improving the combustion chamber, and turbine cascade. The required amount of bench and flight tests has been performed. The engine certification is currently being completed. Specialists at the Antonov State Enterprise and Ivchenko-Progress State Enterprise studied the issue of installing the D-436-148FM engine on the An-148 and An-158 aircraft family. No changes to the design of the engine and aircraft are required. The engine is mounted on the same pylons without changes to the nacelle and engine bonnets. Energy-dependent systems associated with the engine have been investigated. There is no need for the fundamental changes in related systems for the engine’s operational modes according to the Aircraft Flight Manual. An engineering analysis of the comparison of flight-technical and flight-landing characteristics of the An-158 aircraft equipped with the engines D-436-148D and D-436-148FM has been performed. The data were obtained from the flight tests of the An-158 certified aircraft, taking into consideration the wind tunnel studies, flight tests of the An-178 aircraft, data from the An-158 Flight Manual, and the altitude and speed performance of the D-436-148D and D-436-148FM engines. The altitude and speed characteristics of the D-436-148FM engine, which have been calculated, were confirmed by the flight tests of the An-178 aircraft. A feasibility study of engine replacement has been carried out, based on the comparison of the technical and economic characteristics of the An-158 aircraft equipped with the D-436-148D engine and D-436-148FM operated in various atmospheric conditions. The principle of creating a family of aircraft of transport category of different configurations and purposes, based on a single engine, has been proposed","PeriodicalId":18300,"journal":{"name":"MatSciRN: Other Materials Processing & Manufacturing (Topic)","volume":"40 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85065826","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract We report a mesoscale toughening mechanism in polymer nanocomposites that is distinct from previously reported ones. Fractography analysis of epoxy composites with nano-silica additives reveals a stochastic dispersion of nanofiller clusters which creates mesoscale stiffness heterogeneity as confirmed by nanoindentation testing. To analyze the effect of heterogeneity, a finite element model where a crack grows through heterogeneous material was created. Simulations and experimental results indicate that inducing stiffness heterogeneity increases toughness by modification of the crack tip fields. Our results indicate that mesoscale toughening (induced by the nanoparticle additives) plays a significant role in influencing fracture toughness in nanocomposite materials.
{"title":"Heterogeneity-Induced Mesoscale Toughening in Polymer Nanocomposites","authors":"Mithil Kamble, A. Lakhnot, N. Koratkar, C. Picu","doi":"10.2139/ssrn.3539233","DOIUrl":"https://doi.org/10.2139/ssrn.3539233","url":null,"abstract":"Abstract We report a mesoscale toughening mechanism in polymer nanocomposites that is distinct from previously reported ones. Fractography analysis of epoxy composites with nano-silica additives reveals a stochastic dispersion of nanofiller clusters which creates mesoscale stiffness heterogeneity as confirmed by nanoindentation testing. To analyze the effect of heterogeneity, a finite element model where a crack grows through heterogeneous material was created. Simulations and experimental results indicate that inducing stiffness heterogeneity increases toughness by modification of the crack tip fields. Our results indicate that mesoscale toughening (induced by the nanoparticle additives) plays a significant role in influencing fracture toughness in nanocomposite materials.","PeriodicalId":18300,"journal":{"name":"MatSciRN: Other Materials Processing & Manufacturing (Topic)","volume":"36 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78556137","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mayank Doshi, S. Udawant, Datta Devkule, Prof. Santosh Gadekar
Microcontroller based thermoelectric cooling is presented in this paper. The developed prototype uses thermoelectric cooling and forced air cooling for the battery thermal management system. The liquid coolant methods have some adverse effects on battery life and the electric functionality of the overall charging system. There may be the possibility of liquid coolant getting in contact with the battery during the heat extraction operation. Heat is removed from the condenser side of the thermoelectric liquid casing using a motor-operated fan. The entire cooling operation is automatic as it involves the Arduino microcontroller for switching off the thermoelectric cell. LCD display enables data acquisition for future developments. The fast and accurate switching is possible using Arduino microcontroller. The test result presents that cooling is taken place with a reasonable amount of heat extraction from the container.
{"title":"Microcontroller Based Thermoelectric Cooling For Electric Vehicle Battery Charging Application","authors":"Mayank Doshi, S. Udawant, Datta Devkule, Prof. Santosh Gadekar","doi":"10.2139/ssrn.3645352","DOIUrl":"https://doi.org/10.2139/ssrn.3645352","url":null,"abstract":"Microcontroller based thermoelectric cooling is presented in this paper. The developed prototype uses thermoelectric cooling and forced air cooling for the battery thermal management system. The liquid coolant methods have some adverse effects on battery life and the electric functionality of the overall charging system. There may be the possibility of liquid coolant getting in contact with the battery during the heat extraction operation. Heat is removed from the condenser side of the thermoelectric liquid casing using a motor-operated fan. The entire cooling operation is automatic as it involves the Arduino microcontroller for switching off the thermoelectric cell. LCD display enables data acquisition for future developments. The fast and accurate switching is possible using Arduino microcontroller. The test result presents that cooling is taken place with a reasonable amount of heat extraction from the container.","PeriodicalId":18300,"journal":{"name":"MatSciRN: Other Materials Processing & Manufacturing (Topic)","volume":"17 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89634556","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract Fatigue resistance is a crucial requirement to the novel high-entropy alloys when they come to engineering applications, as many metal structures used in practice are failed by cyclic loading. Here, a thorough analysis of the information on the low-cycle fatigue, high-cycle fatigue, crack-growth rates, and fatigue mechanisms in the high-entropy alloy literature unveils a guideline through which the discovery and design of fatigue-resistant high-entropy alloys can be facilitated. Overall, multi-phase alloys, particularly the metastable ones, are favorable to fatigue resistance over single-phase alloys. Suggestions are proposed in the end to accelerate the discovery and design of candidates for fatigue-resistant applications.
{"title":"Discovery and Design of Fatigue-Resistant High-Entropy Alloys","authors":"Weidong Li, Shuying Chen, P. Liaw","doi":"10.2139/ssrn.3603423","DOIUrl":"https://doi.org/10.2139/ssrn.3603423","url":null,"abstract":"Abstract Fatigue resistance is a crucial requirement to the novel high-entropy alloys when they come to engineering applications, as many metal structures used in practice are failed by cyclic loading. Here, a thorough analysis of the information on the low-cycle fatigue, high-cycle fatigue, crack-growth rates, and fatigue mechanisms in the high-entropy alloy literature unveils a guideline through which the discovery and design of fatigue-resistant high-entropy alloys can be facilitated. Overall, multi-phase alloys, particularly the metastable ones, are favorable to fatigue resistance over single-phase alloys. Suggestions are proposed in the end to accelerate the discovery and design of candidates for fatigue-resistant applications.","PeriodicalId":18300,"journal":{"name":"MatSciRN: Other Materials Processing & Manufacturing (Topic)","volume":"4 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-05-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89979710","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-05-18DOI: 10.3846/AVIATION.2020.12815
Swamy Naidu Venkata Neigapula, S. Maddula, Vasishta Bhargava Nukala
Aerodynamic performance of aircraft wings vary with flight path conditions and depend on efficiency of high lift systems. In this work, a study on high lift devices and mechanisms that aim to increase maximum lift coefficient and reduce drag on commercial aircraft wings is discussed. Typically, such extensions are provided to main airfoil along span wise direction of wing and can increase lift coefficient by more than 100% during operation. Increasing the no of trailing edge flaps in chord wise direction could result in 100% increment in lift coefficient at a given angle of attack but leading edge slats improve lift by delaying the flow separation near stall angle of attack. Different combinations of trailing edge flaps used by Airbus, Boeing and McDonnel Douglas manufacturers are explained along with kinematic mechanisms to deploy them. The surface pressure distribution for 30P30N airfoil is evaluated using 2D vortex panel method and effects of chord wise boundary layer flow transitions on aerodynamic lift generation is discussed. The results showed better agreements with experiment data for high Reynolds number (9 million) flow conditions near stall angle of attack.
{"title":"A Study of High Lift Aerodynamic Devices on Commercial Aircrafts","authors":"Swamy Naidu Venkata Neigapula, S. Maddula, Vasishta Bhargava Nukala","doi":"10.3846/AVIATION.2020.12815","DOIUrl":"https://doi.org/10.3846/AVIATION.2020.12815","url":null,"abstract":"Aerodynamic performance of aircraft wings vary with flight path conditions and depend on efficiency of high lift systems. In this work, a study on high lift devices and mechanisms that aim to increase maximum lift coefficient and reduce drag on commercial aircraft wings is discussed. Typically, such extensions are provided to main airfoil along span wise direction of wing and can increase lift coefficient by more than 100% during operation. Increasing the no of trailing edge flaps in chord wise direction could result in 100% increment in lift coefficient at a given angle of attack but leading edge slats improve lift by delaying the flow separation near stall angle of attack. Different combinations of trailing edge flaps used by Airbus, Boeing and McDonnel Douglas manufacturers are explained along with kinematic mechanisms to deploy them. The surface pressure distribution for 30P30N airfoil is evaluated using 2D vortex panel method and effects of chord wise boundary layer flow transitions on aerodynamic lift generation is discussed. The results showed better agreements with experiment data for high Reynolds number (9 million) flow conditions near stall angle of attack.","PeriodicalId":18300,"journal":{"name":"MatSciRN: Other Materials Processing & Manufacturing (Topic)","volume":"122 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-05-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79516138","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The expansive soil obtained from Baure in Yamaltu Deba Local Government Area was rich in clay mineral (montmorillonite), unstable and difficult to use for construction purposes. The soil treated with up to 12% palm kernel shell ash (PKSA an agro – waste) by weight of dry soil to improve index properties and compaction characteristics of the soil using PKSA. Index tests were carried out to classify the natural soil, while the moisture-density relationships were determined by compaction tests on the natural and treated soils using three energy levels viz, British Standard light (BSL), West African Standard (WAS) and British Standard heavy (BSH). BCS used in the study was classified as A-7-5 (20) using the American Association of State Highway and Transportation Officials (AASHTO) and CH group in the Unified Soil Classification System (USCS). Tests results show that specific gravity of the soil increased from 2.29 for the natural to 2.34 at 12% treatment. Liquid limit decreased from 76.2% for natural to 73.4% at 10% PKSA content. Plastic limit increased from 40% for the natural soil to 47.1% at 12% PKSA content treatment. Maximum dry density (MDD) values decreased from 1.44Mg/m3, 1.5Mg/m3 and 1.65Mg/m3 for the natural soil to 1.38Mg/m3 at 10%, 1.45Mg/m3 at 10% and 1.56Mg/m3 at 6% PKSA content for BSL, WAS and BSH compaction energy levels respectively. On the other hand, optimum moisture content (OMC) value decreased from 28.5% and 22.4% for the natural soil to 22.4% and 21.0% at 12% PKSA content for BSL and WAS energies respectively while the value for BSH energy increased from 18.2% to 19.0% at 8% PKSA content. Results show that PKSA is suitable for the improvement of the index properties and compaction characteristics of BCS; and its beneficial use will reduce the attendant disposal problem on the environment.
{"title":"Improvement of the Index and Compaction Characteristics of Black Cotton Soil with Palm Kernel Shell Ash","authors":"Oluwatudimu, O. E., Sadeeq, J. A., O. K. J.","doi":"10.31033/ijemr.10.2.14","DOIUrl":"https://doi.org/10.31033/ijemr.10.2.14","url":null,"abstract":"The expansive soil obtained from Baure in Yamaltu Deba Local Government Area was rich in clay mineral (montmorillonite), unstable and difficult to use for construction purposes. The soil treated with up to 12% palm kernel shell ash (PKSA an agro – waste) by weight of dry soil to improve index properties and compaction characteristics of the soil using PKSA. Index tests were carried out to classify the natural soil, while the moisture-density relationships were determined by compaction tests on the natural and treated soils using three energy levels viz, British Standard light (BSL), West African Standard (WAS) and British Standard heavy (BSH). BCS used in the study was classified as A-7-5 (20) using the American Association of State Highway and Transportation Officials (AASHTO) and CH group in the Unified Soil Classification System (USCS). Tests results show that specific gravity of the soil increased from 2.29 for the natural to 2.34 at 12% treatment. Liquid limit decreased from 76.2% for natural to 73.4% at 10% PKSA content. Plastic limit increased from 40% for the natural soil to 47.1% at 12% PKSA content treatment. Maximum dry density (MDD) values decreased from 1.44Mg/m3, 1.5Mg/m3 and 1.65Mg/m3 for the natural soil to 1.38Mg/m3 at 10%, 1.45Mg/m3 at 10% and 1.56Mg/m3 at 6% PKSA content for BSL, WAS and BSH compaction energy levels respectively. On the other hand, optimum moisture content (OMC) value decreased from 28.5% and 22.4% for the natural soil to 22.4% and 21.0% at 12% PKSA content for BSL and WAS energies respectively while the value for BSH energy increased from 18.2% to 19.0% at 8% PKSA content. Results show that PKSA is suitable for the improvement of the index properties and compaction characteristics of BCS; and its beneficial use will reduce the attendant disposal problem on the environment.","PeriodicalId":18300,"journal":{"name":"MatSciRN: Other Materials Processing & Manufacturing (Topic)","volume":"117 22 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84285236","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-04-30DOI: 10.15587/1729-4061.2020.201540
A. V. Sagalovych, V. Popov, V. Sagalovych, S. Dudnik, Roman Popenchuk
The process of chemical vapor deposition of Mo and Mo-С coatings was studied by means of thermal decomposition of molybdenum hexacarbonyl. The kinetics of the coating growth in the range of 480 °C–540 °C and the pressure in the reaction volume from 9 Pa to 16 Pa were explored. The dependences of coating growth rate, the magnitudes of their microhardness on the parameters of their obtaining, as well as the changes in the morphology of the coating surface, roughness, and structure, were established. The tribological properties of the obtained coatings coupled with bronze Br.Su3H3S20F0.2 were explored at the friction machine 2070 SMT-1 according to the "cube–roller" scheme in a load interval of 0.2–1.4 kN. The lubrication during determining the friction coefficients was carried out by immersion of the movable counter body into a bath with fuel TC-1, GOST 10227-86. It was necessary to conduct such research because there is insufficient information when it comes to the specific equipment and peculiarities of the object onto which a coating is applied. When developing the process of coating application on specific components, techniques, and means to ensure the uniformity of parts heating and precursor feeding to their surface were tested. As a result of the conducted studies, we obtained the regions of parameters of obtaining coatings with different structure, rate, hardness, as well as the patterns of changes in these characteristics at the change of the basic parameters of the process of obtaining such coatings. Depending on application conditions, coatings may have hardness from ~11,000 MPa to 18,000 MPa at a growth rate from 50 μm/h to 170 μm/h. The mean values of the friction coefficient of coatings with different microstructure and microhardness were 0.101 at the load of 0.2 kN and 0.077 at the load of 1.4 kN. Based on the conducted research, it was possible to develop the process of applying the metal and metal-carbide molybdenum-based CVD coatings in regards to the components of the assembly and engine construction, which can serve as the basis for the development of industrial technologies
{"title":"Development of the Chemical Vapor Deposition Process for Applying Molybdenum Coatings on the Components in Assembly and Engine Construction","authors":"A. V. Sagalovych, V. Popov, V. Sagalovych, S. Dudnik, Roman Popenchuk","doi":"10.15587/1729-4061.2020.201540","DOIUrl":"https://doi.org/10.15587/1729-4061.2020.201540","url":null,"abstract":"The process of chemical vapor deposition of Mo and Mo-С coatings was studied by means of thermal decomposition of molybdenum hexacarbonyl. The kinetics of the coating growth in the range of 480 °C–540 °C and the pressure in the reaction volume from 9 Pa to 16 Pa were explored. The dependences of coating growth rate, the magnitudes of their microhardness on the parameters of their obtaining, as well as the changes in the morphology of the coating surface, roughness, and structure, were established. The tribological properties of the obtained coatings coupled with bronze Br.Su3H3S20F0.2 were explored at the friction machine 2070 SMT-1 according to the \"cube–roller\" scheme in a load interval of 0.2–1.4 kN. The lubrication during determining the friction coefficients was carried out by immersion of the movable counter body into a bath with fuel TC-1, GOST 10227-86. It was necessary to conduct such research because there is insufficient information when it comes to the specific equipment and peculiarities of the object onto which a coating is applied. When developing the process of coating application on specific components, techniques, and means to ensure the uniformity of parts heating and precursor feeding to their surface were tested. As a result of the conducted studies, we obtained the regions of parameters of obtaining coatings with different structure, rate, hardness, as well as the patterns of changes in these characteristics at the change of the basic parameters of the process of obtaining such coatings. Depending on application conditions, coatings may have hardness from ~11,000 MPa to 18,000 MPa at a growth rate from 50 μm/h to 170 μm/h. The mean values of the friction coefficient of coatings with different microstructure and microhardness were 0.101 at the load of 0.2 kN and 0.077 at the load of 1.4 kN. Based on the conducted research, it was possible to develop the process of applying the metal and metal-carbide molybdenum-based CVD coatings in regards to the components of the assembly and engine construction, which can serve as the basis for the development of industrial technologies","PeriodicalId":18300,"journal":{"name":"MatSciRN: Other Materials Processing & Manufacturing (Topic)","volume":"60 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84012212","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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