Pub Date : 2016-01-20DOI: 10.4172/2168-9792.1000154
Z. Hong, G. Cao, Chen Wr
With the rising cost of fossil fuels along with greenhouse gas emission such as NOx and COx, use of alternative fuels such as syngas and biofuels is intense interesting, and in the meantime using ceramic matrix composites that eliminate the need of film cooling in combustors, vanes and other hot section components to improve the efficiency of gas turbine engine and reduce the NOx and COx emission becomes increasingly attractive for green engines. However, the alternative fuels have an increased hydrogen/carbon ratio; in turn during combustion it produces more water vapor than the conventional jet fuels. The increased water vapor level will have an impact on the protective oxide scale developed on the gas turbine hot section components, particularly on those made of SiC/SiC ceramic matrix composites (CMC), leading to an accelerated degradation of the turbine components. In addition, some alternative fuels derived from biomass may contain alkali elements such as potassium, sodium and calcium, as well as chlorine, sulfur and/or phosphorus, which may result in possible corrosion of the hot section components in gas turbines, leading to premature failure during service. This paper will review some of the alternative fuels and their combustion products, the possible damages to gas turbine hot section components, as well as some potential protective coatings that may mitigate such damage
{"title":"Green Engines: Possible Damages by Firing Alternative Fuels andProtection","authors":"Z. Hong, G. Cao, Chen Wr","doi":"10.4172/2168-9792.1000154","DOIUrl":"https://doi.org/10.4172/2168-9792.1000154","url":null,"abstract":"With the rising cost of fossil fuels along with greenhouse gas emission such as NOx and COx, use of alternative fuels such as syngas and biofuels is intense interesting, and in the meantime using ceramic matrix composites that eliminate the need of film cooling in combustors, vanes and other hot section components to improve the efficiency of gas turbine engine and reduce the NOx and COx emission becomes increasingly attractive for green engines. However, the alternative fuels have an increased hydrogen/carbon ratio; in turn during combustion it produces more water vapor than the conventional jet fuels. The increased water vapor level will have an impact on the protective oxide scale developed on the gas turbine hot section components, particularly on those made of SiC/SiC ceramic matrix composites (CMC), leading to an accelerated degradation of the turbine components. In addition, some alternative fuels derived from biomass may contain alkali elements such as potassium, sodium and calcium, as well as chlorine, sulfur and/or phosphorus, which may result in possible corrosion of the hot section components in gas turbines, leading to premature failure during service. This paper will review some of the alternative fuels and their combustion products, the possible damages to gas turbine hot section components, as well as some potential protective coatings that may mitigate such damage","PeriodicalId":356774,"journal":{"name":"Journal of Aeronautics and Aerospace Engineering","volume":"316 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124474047","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 : 2015-12-25DOI: 10.4172/2168-9792.1000151
Rathinakumar, Manju Nanda, J. Jayanthi
In safety critical systems such as aerospace, it becomes more important since the non-performance of the system as per the requirement may lead to a catastrophe. Also, the work-around to modify the design as per the requirements, generate code, obtain safety clearance from the authorized agency before porting to the target is very time consuming and a cumbersome approach. In this paper, we propose a model-based approach to improve the performance of the software algorithm and optimize the pitch trim movement before porting the code to the target. The effectiveness of the approach is demonstrated with a case study of aerospacedomain. The approach encompasses the aircraft sub-system dynamics and the software which operates the sub-system. The analysis of the functionality with performance provides a high level of confidence in the software that is to be ported on to the target. The test crew can provide feedback on the overall functionality and performance of the software at the model-level. The proposed approach not only increases the efficacy of the process but also provides higher safety assurance earlier in the process. Pitch-trim is a critical sub-system of the aircraft which is modeled and the improved software algorithm is incorporated into the model for analyzing the overall functionality and performance of the sub-system. Based on the model simulation and analysis result, the changes in the algorithm were made and finally ported onto the target. The performance and functionality of the pitch-trim sub-system on the aircraft was as per the simulation analysis results indicating the correctness of the model and the proposed approach.
{"title":"Optimization of Aircraft Pitch Trim Rate of Movement Using Model BasedApproach and Improving the Software Algorithm","authors":"Rathinakumar, Manju Nanda, J. Jayanthi","doi":"10.4172/2168-9792.1000151","DOIUrl":"https://doi.org/10.4172/2168-9792.1000151","url":null,"abstract":"In safety critical systems such as aerospace, it becomes more important since the non-performance of the system as per the requirement may lead to a catastrophe. Also, the work-around to modify the design as per the requirements, generate code, obtain safety clearance from the authorized agency before porting to the target is very time consuming and a cumbersome approach. In this paper, we propose a model-based approach to improve the performance of the software algorithm and optimize the pitch trim movement before porting the code to the target. The effectiveness of the approach is demonstrated with a case study of aerospacedomain. The approach encompasses the aircraft sub-system dynamics and the software which operates the sub-system. The analysis of the functionality with performance provides a high level of confidence in the software that is to be ported on to the target. The test crew can provide feedback on the overall functionality and performance of the software at the model-level. The proposed approach not only increases the efficacy of the process but also provides higher safety assurance earlier in the process. Pitch-trim is a critical sub-system of the aircraft which is modeled and the improved software algorithm is incorporated into the model for analyzing the overall functionality and performance of the sub-system. Based on the model simulation and analysis result, the changes in the algorithm were made and finally ported onto the target. The performance and functionality of the pitch-trim sub-system on the aircraft was as per the simulation analysis results indicating the correctness of the model and the proposed approach.","PeriodicalId":356774,"journal":{"name":"Journal of Aeronautics and Aerospace Engineering","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126564330","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 : 2015-12-25DOI: 10.4172/2168-9792.1000152
Y. ShagaiyaDaniel
This paper considers the theoretical problem of hydrodynamic and slips boundary conditions over an exponential stretching sheet in the presence of radiation and heat generation/absorption. Similarity solutions are obtained from the governing boundary layer equations for different various of slip parameters, exponential parameter, magnetic field parameter, radiation parameter, heat source parameter, thermophoretic parameter and porosity parameter. The resulting couple system of equations which is highly nonlinear ordinary differential equations are solved semianalytically using homotopy analysis method (HAM). Numerical results are obtained for non-dimensional governing parameters on skin friction, heat and mass transfer coefficient in the presence of suction. Comparison with published results seen in literature is in perfect agreement.
{"title":"Hydromagnetic Nanofluid Flow in the Presence of Radiation and HeatGeneration/Absorption Past an Exponential Stretching Sheet with SlipBoundary Conditions Using HAM","authors":"Y. ShagaiyaDaniel","doi":"10.4172/2168-9792.1000152","DOIUrl":"https://doi.org/10.4172/2168-9792.1000152","url":null,"abstract":"This paper considers the theoretical problem of hydrodynamic and slips boundary conditions over an exponential stretching sheet in the presence of radiation and heat generation/absorption. Similarity solutions are obtained from the governing boundary layer equations for different various of slip parameters, exponential parameter, magnetic field parameter, radiation parameter, heat source parameter, thermophoretic parameter and porosity parameter. The resulting couple system of equations which is highly nonlinear ordinary differential equations are solved semianalytically using homotopy analysis method (HAM). Numerical results are obtained for non-dimensional governing parameters on skin friction, heat and mass transfer coefficient in the presence of suction. Comparison with published results seen in literature is in perfect agreement.","PeriodicalId":356774,"journal":{"name":"Journal of Aeronautics and Aerospace Engineering","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115489968","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 : 2015-12-20DOI: 10.4172/2168-9792.1000153
G. Cheng, Y. Ito, C. Yen‐Sen, W. Ten-See
The objective of this study was to develop an efficient and accurate computational methodology to predict detailed thermo-fluid environments of a single flow element in a hypothetical solid-core nuclear thermal thrust chamber assembly. Several numerical and multi-physics thermo-fluid models, such as chemical reactions, turbulence, conjugate heat transfer, porosity, and power generation, were incorporated into an unstructured-grid, pressure-based computational fluid dynamics solver used in this investigation. A secondary objective was to develop a porosity model for simulation of the whole solid-core nuclear thermal engine without resolving thousands of flow channels inside the solid core. Detailed numerical simulations of a single flow element with different power generation profiles were conducted to investigate the root cause of a phenomenon called mid-section corrosion that severely damaged the flow element assembly of early solid-core reactors. Under the assumptions employed in this effort and for the first time, the result demonstrated flow choking in the flow element. The possibility of flow choking in part of the flow element indicated a potential coolant mass flow imbalance, which could lead to a high local thermal gradient in coolant-starved flow elements and possibly the eventual mid-section corrosion.
{"title":"Numerical Study of Single Flow Element in a Nuclear Thermal Thrust Chamber","authors":"G. Cheng, Y. Ito, C. Yen‐Sen, W. Ten-See","doi":"10.4172/2168-9792.1000153","DOIUrl":"https://doi.org/10.4172/2168-9792.1000153","url":null,"abstract":"The objective of this study was to develop an efficient and accurate computational methodology to predict detailed thermo-fluid environments of a single flow element in a hypothetical solid-core nuclear thermal thrust chamber assembly. Several numerical and multi-physics thermo-fluid models, such as chemical reactions, turbulence, conjugate heat transfer, porosity, and power generation, were incorporated into an unstructured-grid, pressure-based computational fluid dynamics solver used in this investigation. A secondary objective was to develop a porosity model for simulation of the whole solid-core nuclear thermal engine without resolving thousands of flow channels inside the solid core. Detailed numerical simulations of a single flow element with different power generation profiles were conducted to investigate the root cause of a phenomenon called mid-section corrosion that severely damaged the flow element assembly of early solid-core reactors. Under the assumptions employed in this effort and for the first time, the result demonstrated flow choking in the flow element. The possibility of flow choking in part of the flow element indicated a potential coolant mass flow imbalance, which could lead to a high local thermal gradient in coolant-starved flow elements and possibly the eventual mid-section corrosion.","PeriodicalId":356774,"journal":{"name":"Journal of Aeronautics and Aerospace Engineering","volume":"47 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123362605","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 : 2015-12-20DOI: 10.4172/2168-9792.1000150
Y. Menail, A. Mahi, M. Assarar
This paper presents the experimental results of the influence of water ageing after mechanical on glassfiber composites, compared with Kevlar-fiber composites. The tested specimens were subjected to fatigue during various numbers of cycles (100 to 50000). After that, they were immersed into tap water and simulated seawater for different periods (4, 20 and 40 days). Next, the tensile tests were made on the unaged and aged samples in order to determine the evolution of the strength and stiffness under local interactions of the water absorption and fatigue. The obtained results showed that tensile characteristics were clearly affected by the immersion treatment and fatigue loading. In fact, the residual stiffness and residual strength decreased when the immersion time and cycle number of fatigue increased, indicating that the studied composites have experienced some forms of mechanical damage
{"title":"Effect of Fatigue Testing and Aquatic Environment on the TensileProperties of Glass and Kevlar Fibers Reinforced Epoxy Composites","authors":"Y. Menail, A. Mahi, M. Assarar","doi":"10.4172/2168-9792.1000150","DOIUrl":"https://doi.org/10.4172/2168-9792.1000150","url":null,"abstract":"This paper presents the experimental results of the influence of water ageing after mechanical on glassfiber composites, compared with Kevlar-fiber composites. The tested specimens were subjected to fatigue during various numbers of cycles (100 to 50000). After that, they were immersed into tap water and simulated seawater for different periods (4, 20 and 40 days). Next, the tensile tests were made on the unaged and aged samples in order to determine the evolution of the strength and stiffness under local interactions of the water absorption and fatigue. The obtained results showed that tensile characteristics were clearly affected by the immersion treatment and fatigue loading. In fact, the residual stiffness and residual strength decreased when the immersion time and cycle number of fatigue increased, indicating that the studied composites have experienced some forms of mechanical damage","PeriodicalId":356774,"journal":{"name":"Journal of Aeronautics and Aerospace Engineering","volume":"114 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132883719","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 : 2015-11-28DOI: 10.4172/2168-9792.1000148
W. Harasani
The scope of the present work was to design, build and fly test a solar UAV, Sun Falcon 2 for long endurance day and night flight operations. A software program was written to design the UAV with appropriate aerodynamic attributes, power requirements and other flight mission constraints to keep the vehicle airborne for multi day and night operations. More specifically the design called for an least 12 hours of endurance during the day with solar panels deployed to absorb sufficient daylight energy to top up the on board batteries for the complete subsequent night flight mission. With Sun radiation levels averaging at about 6003 W/m2 during the Saudi day it was not too difficult to conform to multi day and night design requirements. The prototype Sun Falcon 2 has already been built and flight tested with satisfactory performance records satisfying the design criteria.
{"title":"Designing and Fly Testing a Long Endurance Solar Unmanned Air Vehicle","authors":"W. Harasani","doi":"10.4172/2168-9792.1000148","DOIUrl":"https://doi.org/10.4172/2168-9792.1000148","url":null,"abstract":"The scope of the present work was to design, build and fly test a solar UAV, Sun Falcon 2 for long endurance day and night flight operations. A software program was written to design the UAV with appropriate aerodynamic attributes, power requirements and other flight mission constraints to keep the vehicle airborne for multi day and night operations. More specifically the design called for an least 12 hours of endurance during the day with solar panels deployed to absorb sufficient daylight energy to top up the on board batteries for the complete subsequent night flight mission. With Sun radiation levels averaging at about 6003 W/m2 during the Saudi day it was not too difficult to conform to multi day and night design requirements. The prototype Sun Falcon 2 has already been built and flight tested with satisfactory performance records satisfying the design criteria.","PeriodicalId":356774,"journal":{"name":"Journal of Aeronautics and Aerospace Engineering","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114126004","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 : 2015-11-28DOI: 10.4172/2168-9792.1000147
M. Mirzaee, Sepideh Behroozifar
ADF or Automatic Direction Finder is one of the basic navigation machines which works based on the waves at low and medium frequencies. Tuning capacitors and selecting the appropriate circuit for each band embedded in receiver and is controlling by signals which are sending from the user from the controller section. Electromechanical systems of current receiver has reduced system performance in terms of size, weight, maintenance and accuracy of performance, and increases construction costs and the development of electronic instrumentation compared to the existing systems, the proposal design is based on electronic devices. In addition, due to the advantages of digital implementation in terms of accuracy, cost and ease of manufacturing, processing and detection of mixed signals, the choice of frequencies and the angle transmitter calculating is implemented by the digital transmitter.
{"title":"DADF (Digital Automatic Direction Finder)","authors":"M. Mirzaee, Sepideh Behroozifar","doi":"10.4172/2168-9792.1000147","DOIUrl":"https://doi.org/10.4172/2168-9792.1000147","url":null,"abstract":"ADF or Automatic Direction Finder is one of the basic navigation machines which works based on the waves at low and medium frequencies. Tuning capacitors and selecting the appropriate circuit for each band embedded in receiver and is controlling by signals which are sending from the user from the controller section. Electromechanical systems of current receiver has reduced system performance in terms of size, weight, maintenance and accuracy of performance, and increases construction costs and the development of electronic instrumentation compared to the existing systems, the proposal design is based on electronic devices. In addition, due to the advantages of digital implementation in terms of accuracy, cost and ease of manufacturing, processing and detection of mixed signals, the choice of frequencies and the angle transmitter calculating is implemented by the digital transmitter.","PeriodicalId":356774,"journal":{"name":"Journal of Aeronautics and Aerospace Engineering","volume":"67 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122062564","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 : 2015-11-28DOI: 10.4172/2168-9792.1000149
Y. Minami
The distance to a stellar system is too huge, therefore the travel to the fixed star nearest to the Earth using the present propulsion technology will require tens of thousands years. In order to overcome such a limit of the space travel between fixed stars, research and development of a new propulsion theory and navigation theory are indispensable. As a promising approach, space drive propulsion theory and Hyper-Space navigation method given by a space-time featuring an imaginary time (i.e., Time-Hole) are introduced. Space drive propulsion system is one of field propulsion system utilizing the action of the medium of strained or deformed field of space. The curvature of space plays a significant role for the propulsion theory. On the other hand, a plunging into Hyper-Space characterized by imaginary time would make the interstellar travel possible in a short time. The Hyper-Space navigation theory would allow a starship to start at any time and from any place for an interstellar travel to the farthest star systems, the whole mission time being within human lifetime. Space propulsion physics such as propulsion theory and navigation theory give us a concrete theoretical method toward galaxy exploration. This paper describes a summary of each theme (Continuum mechanics of Space-Time, Space drive propulsion, Hyper-Space navigation) published so far by author.
{"title":"Space Propulsion Physics toward Galaxy Exploration","authors":"Y. Minami","doi":"10.4172/2168-9792.1000149","DOIUrl":"https://doi.org/10.4172/2168-9792.1000149","url":null,"abstract":"The distance to a stellar system is too huge, therefore the travel to the fixed star nearest to the Earth using the present propulsion technology will require tens of thousands years. In order to overcome such a limit of the space travel between fixed stars, research and development of a new propulsion theory and navigation theory are indispensable. As a promising approach, space drive propulsion theory and Hyper-Space navigation method given by a space-time featuring an imaginary time (i.e., Time-Hole) are introduced. Space drive propulsion system is one of field propulsion system utilizing the action of the medium of strained or deformed field of space. The curvature of space plays a significant role for the propulsion theory. On the other hand, a plunging into Hyper-Space characterized by imaginary time would make the interstellar travel possible in a short time. The Hyper-Space navigation theory would allow a starship to start at any time and from any place for an interstellar travel to the farthest star systems, the whole mission time being within human lifetime. Space propulsion physics such as propulsion theory and navigation theory give us a concrete theoretical method toward galaxy exploration. This paper describes a summary of each theme (Continuum mechanics of Space-Time, Space drive propulsion, Hyper-Space navigation) published so far by author.","PeriodicalId":356774,"journal":{"name":"Journal of Aeronautics and Aerospace Engineering","volume":"89 4","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120921324","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 : 2015-10-25DOI: 10.4172/2168-9792.1000146
L. Nair
Analytical solutions with the KS element equations of motion due to the combined effect of zonal harmonics J2,J3 and J4 and drag by considering an analytical oblate diurnal exponential density model when density scale height varies with altitude is obtained using series expansion method. Terms up to third terms in e, eccentricity, c, a small parameter depending on the ellipticity of the atmosphere and second order terms in μ, gradient of the scale height altitude are considered. The KS element equations are numerically integrated (NUM) through a fixed step size fourth-order Runge-Kutta-Gill method having a very small step-size of half degree in the eccentric anomaly for comparing analytically integrated (ANAL) values. After 100 revolutions, decrease in argument of perigee, ω, at perigee height = 400 kilometer, e = 0.1 and inclination i = 20 and 80 degrees, are found to be 7.42 and 39.8 degrees. At i =80 degree, the percentage error = (ANAL - NUM) / NUM after 1 and 100 revolutions are 0.61 and 2.09.
{"title":"Variation in Argument of Perigee for Near-Earth Satellite Orbits Perturbedby Earths Oblateness and Atmospheric Drag Interms of Ks Elements","authors":"L. Nair","doi":"10.4172/2168-9792.1000146","DOIUrl":"https://doi.org/10.4172/2168-9792.1000146","url":null,"abstract":"Analytical solutions with the KS element equations of motion due to the combined effect of zonal harmonics J2,J3 and J4 and drag by considering an analytical oblate diurnal exponential density model when density scale height varies with altitude is obtained using series expansion method. Terms up to third terms in e, eccentricity, c, a small parameter depending on the ellipticity of the atmosphere and second order terms in μ, gradient of the scale height altitude are considered. The KS element equations are numerically integrated (NUM) through a fixed step size fourth-order Runge-Kutta-Gill method having a very small step-size of half degree in the eccentric anomaly for comparing analytically integrated (ANAL) values. After 100 revolutions, decrease in argument of perigee, ω, at perigee height = 400 kilometer, e = 0.1 and inclination i = 20 and 80 degrees, are found to be 7.42 and 39.8 degrees. At i =80 degree, the percentage error = (ANAL - NUM) / NUM after 1 and 100 revolutions are 0.61 and 2.09.","PeriodicalId":356774,"journal":{"name":"Journal of Aeronautics and Aerospace Engineering","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124876256","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 : 2015-10-24DOI: 10.4172/2168-9792.1000145
Luiz Sampaio Athayde Junior
According to the first law of Kepler, the planets orbit the sun in elliptical path. This ellipse causes a slowdown in the world when it goes from the nearest point of the sun to the farthest point and also causes acceleration when the opposite occurs. This variation of the velocity of the planet combined with the inclination of its imaginary axis creates the analemma chart, which can be found with the overlap of the positions of the sun in a particular location always in the same timeset on a watch. The analema, in turn, describes variations in the durations of the solar day. In some dates, these variations in solar days occur in accordance with the change in velocity of the planet, but at other times, they get along perfectly Conversely, showing in some parts of the solar days year that will gradually reducing their periods as the planet decelerates and also increases periods as the planet accelerates.
{"title":"Paradoxical Variation of the Solar Day Related to Kepler/Newton System","authors":"Luiz Sampaio Athayde Junior","doi":"10.4172/2168-9792.1000145","DOIUrl":"https://doi.org/10.4172/2168-9792.1000145","url":null,"abstract":"According to the first law of Kepler, the planets orbit the sun in elliptical path. This ellipse causes a slowdown in the world when it goes from the nearest point of the sun to the farthest point and also causes acceleration when the opposite occurs. This variation of the velocity of the planet combined with the inclination of its imaginary axis creates the analemma chart, which can be found with the overlap of the positions of the sun in a particular location always in the same timeset on a watch. The analema, in turn, describes variations in the durations of the solar day. In some dates, these variations in solar days occur in accordance with the change in velocity of the planet, but at other times, they get along perfectly Conversely, showing in some parts of the solar days year that will gradually reducing their periods as the planet decelerates and also increases periods as the planet accelerates.","PeriodicalId":356774,"journal":{"name":"Journal of Aeronautics and Aerospace Engineering","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127966519","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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