WSEAS Transactions on Applied and Theoretical Mechanics最新文献_第2页

Energy Efficiency Analysis of Natural Convection Heat Transfer in Concentric Annulus with Interior and Exterior Grooves 带有内部和外部凹槽的同心环中自然对流传热的能效分析

WSEAS Transactions on Applied and Theoretical Mechanics Pub Date : 2023-12-07 DOI: 10.37394/232011.2023.18.25

K. B. Abdelmlek, F. B. Nejma

{"title":"Energy Efficiency Analysis of Natural Convection Heat Transfer in Concentric Annulus with Interior and Exterior Grooves","authors":"K. B. Abdelmlek, F. B. Nejma","doi":"10.37394/232011.2023.18.25","DOIUrl":"https://doi.org/10.37394/232011.2023.18.25","url":null,"abstract":"This study is a numerical investigation of the convective heat transfer in motionless concentric annulus composed of two horizontal cylinders, one of which is grooved. The inner cylinder is kept at hot temperature Th and the outer one is kept at cold temperature Tc. The aim of this paper is to analyze the effect of the groove on thermal and dynamic behavior in the annulus when the groove is located on the hot cylinder (inner groove), and when it is located on the cold cylinder (exterior groove). To observe the effect the inner and outer groove on the flow structure and on the heat transfer rate, the groove is positioned at ϕ0=-90̊, -45̊, 0 ̊, 45 ̊, and 90̊. Moreover, the groove size (f) and the radius ratio (e) of the annulus have been changed to investigate their effects on heat transfer rate as well as on the energy efficiency of the process. The results show that the heat transfer rate rises up with the increase of Rayleigh number. It is seen that; in the case of the inner groove; the heat transfer rate reaches a maximum at ϕ0=40̊, whatever the groove size. Furthermore, the energy efficiency of the process is maximum when the inner groove is positioned at ϕ0=90̊, and it increases well with the increase of f. On the other hand, in the case of the exterior groove, the heat transfer rate is practically close to that of non-grooved annulus for f<0.7. A decrease of 34% of the energy efficiency is noticed with the increase of the size of the groove to f=0.7. Our results would be very useful for manufacturers who are looking for increasing the energy efficiency of their process, or also who need to boost or decrease the heat transfer rate depending on the objective of their process.","PeriodicalId":53603,"journal":{"name":"WSEAS Transactions on Applied and Theoretical Mechanics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-12-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138593635","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}

引用次数: 0

Derivation of Key Characteristics of Columns in Frames with Sway 带摇摆框架中柱的关键特性推导

WSEAS Transactions on Applied and Theoretical Mechanics Pub Date : 2023-11-14 DOI: 10.37394/232011.2023.18.24

Jostein Hellesland

{"title":"Derivation of Key Characteristics of Columns in Frames with Sway","authors":"Jostein Hellesland","doi":"10.37394/232011.2023.18.24","DOIUrl":"https://doi.org/10.37394/232011.2023.18.24","url":null,"abstract":"The paper paper examines columns of elastic frames that are able to displace laterally under axial load. Columns on the same level (story) of such frames may contribute to lateral support (stability) or require lateral support (supported columns). In the former case, maximum moments will occur at column ends, but may occur between column ends in the latter case. The column response, including the formation of moments and shears, is often complicated, often calling for approximate analysis methods and information that presently may not be readily available. Main attention of the paper is paid to providing results that will be helpful in providing, in a rather simple manner, improved understanding of column mechanics, and that may be helpful also as a supplement to full second-order analyses. Towards this goal, the major objective of the paper is threefold: (i) to identify characteristic points, or behavioral“landmarks” in the axial load-moment solution space, through the study of rotationally restrained elastic columns and two-column panels with sidesway; (ii) to derive simple, novel, closed-form expressions for these, thereby providing a tool simplifying the establishment of the variation of end and maximum moments versus axial load; (iii) to identify to what extent isolated (single) column analyses may adequately represent horizontally interacting columns, and potential unwinding, in frames.","PeriodicalId":53603,"journal":{"name":"WSEAS Transactions on Applied and Theoretical Mechanics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134954221","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}

引用次数: 0

Modelling of Crack Formation and Growth using FEM for Selected Structural Materials at Static Loading 选定结构材料在静载荷作用下裂纹形成和扩展的有限元模拟

WSEAS Transactions on Applied and Theoretical Mechanics Pub Date : 2023-11-01 DOI: 10.37394/232011.2023.18.23

Vladislav Kozák, Jiří Vala

引用次数: 0

Application of Acoustic-solid Coupling Theory in New Energy Vehicle Noise Control 声固耦合理论在新能源汽车噪声控制中的应用

WSEAS Transactions on Applied and Theoretical Mechanics Pub Date : 2023-10-26 DOI: 10.37394/232011.2023.18.22

Fujun Mao

{"title":"Application of Acoustic-solid Coupling Theory in New Energy Vehicle Noise Control","authors":"Fujun Mao","doi":"10.37394/232011.2023.18.22","DOIUrl":"https://doi.org/10.37394/232011.2023.18.22","url":null,"abstract":"The development of new energy vehicles has attracted much attention due to the strong promotion and popularisation of the concept of low carbon and environmental protection, and the increasing demand for environmental protection in cars. Although these vehicles meet people’s requirements for resource and environmental protection, the noise generated during the driving process affects the comfort of the vehicle occupants and the concentration of the vehicle driver. To address this problem, the research proposes to improve the noise control technology of new energy vehicles based on acoustic-solid coupling theory and to test the practical application effect of this technology. The test results show that the maximum acceleration of vibration at the roof, floor, axle head, and spring of the new energy vehicle are 1.48 m/s2, 1.02 m/s2, 0.079 m/s2, and 0.020 m/s2 respectively, which are lower than the maximum acceleration before the use of this technology. The maximum sound pressure at the windscreen and side window glass of the new energy vehicle is 80 dB(A) and 73 dB(A) after the use of this technology. The maximum sound pressure at the driver’s ear was 62 dB(A) and 77 dB(A) when the vehicle was driven on different road surfaces, which were lower than the sound pressure values before use. In summary, the research proposes to improve the noise control technology of new energy vehicles based on the sound-solid coupling theory, which can have the effect of reducing the noise value generated by new energy vehicles and improving the comfort of users.","PeriodicalId":53603,"journal":{"name":"WSEAS Transactions on Applied and Theoretical Mechanics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134907029","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}

引用次数: 0

A Mathematical method for Calculating the Retentive Force of Ring Clasps when Designing the Removable Partial Denture Metal Frame 设计可摘局部义齿金属架时计算环卡环固位力的数学方法

WSEAS Transactions on Applied and Theoretical Mechanics Pub Date : 2023-10-23 DOI: 10.37394/232011.2023.18.21

Laith Mahmoud Abdulhadi Al-Samawi

{"title":"A Mathematical method for Calculating the Retentive Force of Ring Clasps when Designing the Removable Partial Denture Metal Frame","authors":"Laith Mahmoud Abdulhadi Al-Samawi","doi":"10.37394/232011.2023.18.21","DOIUrl":"https://doi.org/10.37394/232011.2023.18.21","url":null,"abstract":"Practically, calculating the retentive force of the clasps used as a part of removable partial dentures testing of general retention. This test is done using a universal testing machine or a pull test kit. However, these techniques aren't feasible until after designing and fabricating the framework. Therefore, a calculating method or formula based on the variables affecting the retentive force of any clasp seems necessary while developing the framework and before the final casting of the partial denture. The objective of this experiment is to determine the formula that mathematically estimates the pulling force of four-ring clasps in vitro. The experiment included the fabrication and recording of pullout forces for four types of ring clasps; then, the variables were identified and related to the retentive force mathematically. An equation was generated to count the retentive force for the four clasps and assess the precision of the results. In addition, the retentive arm sizes were correlated to the pulling forces using the Pearson coefficient. In conclusion, a new mathematical method was presented to the profession using simple math. The method is a practical and simple way to enhance the selection of clasps concerning their retentive force in addition to the other design factors. Therefore, additional tools for creating the removable partial denture with a bio-protective concept were displayed, and further research should be done to analyze the force generated by other clasps to make a global system to be added to the software for designing the partial dental framework.","PeriodicalId":53603,"journal":{"name":"WSEAS Transactions on Applied and Theoretical Mechanics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135412634","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}

引用次数: 0

Addressing the Primary and Subharmonic Resonances of the Swing Equation 求解摆动方程的主谐波和次谐波共振

WSEAS Transactions on Applied and Theoretical Mechanics Pub Date : 2023-10-13 DOI: 10.37394/232011.2023.18.19

Anastasia Sofroniou, Bhairavi Premnath

{"title":"Addressing the Primary and Subharmonic Resonances of the Swing Equation","authors":"Anastasia Sofroniou, Bhairavi Premnath","doi":"10.37394/232011.2023.18.19","DOIUrl":"https://doi.org/10.37394/232011.2023.18.19","url":null,"abstract":"A research investigation is undertaken to gain a more comprehensive understanding of the primary and subharmonic resonances exhibited by the swing equation. The occurrence of the primary resonance is characterised by amplified oscillatory reactions, voltage instability, and the possibility for system failure. The phenomenon of subharmonic resonance arises when the frequency of disturbance is a whole-number fraction of the natural frequency. This results in the occurrence of low-frequency oscillations and the potential for detrimental effects on equipment. The objective of this study is to expand upon the current literature regarding the impacts of primary resonance and enhance comprehension of subharmonic resonance in relation to the stability of a specific power system model. The analytical and numerical tools are utilised to investigate the fundamental principles of this resonant-related problem, aiming to provide an effective control solution. This choice is driven by the model’s complex nonlinear dynamical behaviour, which offers valuable insights for further analysis. This analysis includes the Floquet Method, the Method of strained parameters, and the concept of tangent instability in order to provide an extension to existing literature relating to primary and subharmonic resonances, taking into account the dynamic and bifurcation characteristics of the swing equation. This objective will be achieved through the utilisation of both analytical and numerical methods, enabling the identification of specific indicators of chaos that can contribute to the safe operation of real-world scenarios.","PeriodicalId":53603,"journal":{"name":"WSEAS Transactions on Applied and Theoretical Mechanics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135858512","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}

引用次数: 0

Torsion of the Truncated Hollow Orthotropic Elastic Body of Rotation 截断空心正交各向异性旋转弹性体的扭转

WSEAS Transactions on Applied and Theoretical Mechanics Pub Date : 2023-10-13 DOI: 10.37394/232011.2023.18.18

István Ecsedi, Attila Baksa, Marwen Habbachi

引用次数: 0

Methodology for 3D Scanning of Objects 物体三维扫描方法学

WSEAS Transactions on Applied and Theoretical Mechanics Pub Date : 2023-10-13 DOI: 10.37394/232011.2023.18.20

Miglena Paneva, Peter Panev, Nikolay Stoimenov, Stanislav Gyoshev

引用次数: 0

Finding the Weight Difference of a Rectangular Structure with a Parabolic Arc for Mathematical Models Made of Steel and other Composite Materials 用钢和其他复合材料制作的数学模型求带抛物线的矩形结构的重量差

WSEAS Transactions on Applied and Theoretical Mechanics Pub Date : 2023-09-28 DOI: 10.37394/232011.2023.18.17

Tymor Abed Alsttar Sediqer, Emad Toma Karash, Jamal Nayief Sultan, Majid Khaleel Najem

{"title":"Finding the Weight Difference of a Rectangular Structure with a Parabolic Arc for Mathematical Models Made of Steel and other Composite Materials","authors":"Tymor Abed Alsttar Sediqer, Emad Toma Karash, Jamal Nayief Sultan, Majid Khaleel Najem","doi":"10.37394/232011.2023.18.17","DOIUrl":"https://doi.org/10.37394/232011.2023.18.17","url":null,"abstract":"The most popular materials for lightweight constructions, including building and aircraft structures, industrial, military, and aerospace technology, are armored composites. Composites made of carbon fiber are typically employed in lightweight applications. The ANSYS program was used to produce four mathematical models. Steel is used in the construction of the first and second versions whereas composite materials are used in the third and fourth variants. To find all the deformations, stresses, and strains that appear on the four models, as well as to calculate the weights of those four structures and compare them, these four models were tested with the ANSYS 15.0 program to obtain equal deformation resistance for all models under the influence of different loads. The results show that the composite models had lower strains, stresses, and deformations than the steel models. Among other results, it was discovered that the weight of the third model made of composite materials decreased by (32.72%) compared to the steel-based first model, and after doing the necessary calculations and assessing the results, the fourth model made of composite materials' weight was reduced by (19.21%) when compared to the second model made of steel.","PeriodicalId":53603,"journal":{"name":"WSEAS Transactions on Applied and Theoretical Mechanics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135387893","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}

引用次数: 0

Experimental Determination of Grinding Parameters using a Ball Mill with Innovative Lifters 采用新型提升装置的球磨机磨削参数的实验确定

WSEAS Transactions on Applied and Theoretical Mechanics Pub Date : 2023-09-25 DOI: 10.37394/232011.2023.18.16

Miglena Paneva, Peter Panev, Nikolay Stoimenov

引用次数: 0