Acta Polytechnica最新文献_第5页

Parametric study of the energy potential of a building’s envelope with integrated energy-active elements 具有集成能量有源元件的建筑围护结构能量势能的参数研究

IF 0.8

Acta Polytechnica Pub Date : 2022-12-31 DOI: 10.14311/ap.2022.62.0595

D. Kalús, Daniela Koudelková, Veronika Mučková, Martin Sokol, Mária Kurčová, P. Šťastný

{"title":"Parametric study of the energy potential of a building’s envelope with integrated energy-active elements","authors":"D. Kalús, Daniela Koudelková, Veronika Mučková, Martin Sokol, Mária Kurčová, P. Šťastný","doi":"10.14311/ap.2022.62.0595","DOIUrl":"https://doi.org/10.14311/ap.2022.62.0595","url":null,"abstract":"Building structures with integrated energy-active elements (BSIEAE) present a progressive alternative for building construction with multifunctional energy functions. The aim was to determine the energy potential of a building envelope with integrated energy-active elements in the function of direct-heating, semi-accumulation and accumulation of large-area radiant heating. The research methodology consists in an analysis of building structures with energy-active elements, creation of mathematical-physical models based on the simplified definition of heat and mass transfer in radiant large-area heating, and a parametric study of the energy potential of individual variants of technical solutions. The results indicate that the increase in heat loss due to the location of the tubes in the structure closer to the exterior is negligible for Variant II, semi-accumulation heating, and Variant III, accumulation heating, as compared to Variant I, direct heating, it is below 1 % of the total delivered heat flux. The direct heat flux to the heated room is 89.17 %, 73.36 %, and 58.46 % of the total heat flux for Variant I, Variant II and Variant III, respectively. For Variant II and Variant III, the heat storage accounts for 14.84 %, and 29.86 % of the total heat flux, respectively. Variants II and III appear to be promising in terms of heat/cool accumulation with an assumption of lower energy demand (at least 10 %) than for low inertia walls. We plan to extend these simplified parametric studies with dynamic computer simulations to optimise the design and composition of the panels with integrated energy-active elements.","PeriodicalId":45804,"journal":{"name":"Acta Polytechnica","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2022-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47015626","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: 1

Design and simulation of a bearing housing aerospace component from titanium alloy (Ti6Al4V) for additive manufacturing 用于增材制造的钛合金(Ti6Al4V)航空部件轴承座的设计与仿真

IF 0.8

Acta Polytechnica Pub Date : 2022-12-31 DOI: 10.14311/ap.2022.62.0639

Moses Oyesola, K. Mpofu, I. Daniyan, N. Mathe

{"title":"Design and simulation of a bearing housing aerospace component from titanium alloy (Ti6Al4V) for additive manufacturing","authors":"Moses Oyesola, K. Mpofu, I. Daniyan, N. Mathe","doi":"10.14311/ap.2022.62.0639","DOIUrl":"https://doi.org/10.14311/ap.2022.62.0639","url":null,"abstract":"In evaluating emerging technology, such as additive manufacturing, it is important to analyse the impact of the manufacturing process on efficiency in an objective and quantifiable manner. This study deals with the design and simulation of a bearing housing made from titanium alloy (Ti6Al4V) using the selective laser melting (SLM) technique. The Finite Element Analysis (FEA) method was used for assessing the suitability of Ti6Al4V for aerospace application. The choice of Ti6Al4V is due to the comparative advantage of its strength-to-weight ratio. The implicit and explicit modules of the Abaqus software were employed for the non-linear and linear analyses of the component part. The results obtained revealed that the titanium alloy (Ti6Al4V) sufficiently meets the design, functional and service requirements of the bearing housing component produced for aerospace application. The designed bearing is suitable for a high speed and temperature application beyond 1900 K, while the maximum stress induced in the component during loading was 521 kPa. It is evident that the developed stresses do not result in a distortion or deformation of the material with yield strength in the region of 820 MPa. This work provides design data for the development of a bearing housing for AM under the technique of SLM using Ti6Al4V by reflecting the knowledge of the material behaviour under the operating conditions.","PeriodicalId":45804,"journal":{"name":"Acta Polytechnica","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2022-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44396990","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: 1

Conversion of units of length from the Czech state standard to the geodetic baseline Javoriv 将捷克国家标准的长度单位转换为Javoriv大地测量基线

IF 0.8

Acta Polytechnica Pub Date : 2022-12-31 DOI: 10.14311/ap.2022.62.0618

J. Lechner, N. Kosarev, Igor Sergeevich Trevoho

{"title":"Conversion of units of length from the Czech state standard to the geodetic baseline Javoriv","authors":"J. Lechner, N. Kosarev, Igor Sergeevich Trevoho","doi":"10.14311/ap.2022.62.0618","DOIUrl":"https://doi.org/10.14311/ap.2022.62.0618","url":null,"abstract":"Modern society cannot do without high quality geospatial data. This need constantly strengthens with the growth of the information society and the emerging cyber society. Validity and quality of geospatial data is strongly connected to the level of its metrological service. It is necessary to conduct National metrological comparisons, in order to maintain an effective measuring infrastructure both inside a single country and in the whole Europe. The main result of such a comparison is a validation of actual values of key parameters of state standards.The article presents results of a conversion of unit of length of the state standard of the Czech Republic to the geodetic baseline Javoriv (Ukraine), as performed by the staff of the Research Institute of Geodesy, Topography and Cartography (RIGTC). The conversion was realised in cooperation with Lviv Polytechnic National University (Ukraine). High-precision measuring equipment used during the conversion includes: the Leica AT401 laser tracker and the Leica Nova MS50 electronic total station.A comparison of the measured length sections of the geodetic baseline Javoriv, performed by VUGTK employees, with the measurement results performed on a geodetic baseline Javoriv by specialists of the National Science Center (NSC) Institute of Metrology, gave a very good consistency. This is a sign of high quality results of comparative international measurement. It is planned to continue with the common efforts in the field of comparative international measurements between the Czech Republic and Ukraine in order to determine the actual values of the length sections of the geodetic baseline Javoriv.","PeriodicalId":45804,"journal":{"name":"Acta Polytechnica","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2022-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49503240","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

IF 0.8

Acta Polytechnica Pub Date : 2022-12-31 DOI: 10.14311/ap.2022.62.0654

Linda Veselá

{"title":"Recommended procedure for headroom design according to geometric parameters of building structures","authors":"Linda Veselá","doi":"10.14311/ap.2022.62.0654","DOIUrl":"https://doi.org/10.14311/ap.2022.62.0654","url":null,"abstract":"The system of Czech technical standards for geometric accuracy assumes that the designer determines the functional geometric parameters for a specific building. By calculation, he verifies them in the so-called “geometric plan” in the project documentation. The functional geometric parameters should be determined primarily for critical elements, i.e. for structures whose geometric accuracy is important for the execution of subsequent works, such as technologies requiring high precision and specific structures. The assumption is that designers will incorporate variations in geometric accuracy primarily in the development of the spatial parameters of the structures, which should ensure that the dimensional requirements for the completed structures will be met. One of these parameters is headroom. The design of headroom must respect the minimum height requirements prescribed by legislation, and where appropriate, by technical standards. At the same time, the design must respect the technological possibilities of the construction of individual structures – geometric deviations. To comply with the dimensional requirements for the completed structures, the geometric accuracy deviations should be determined in accordance with the requirements of the technical standards for the execution of the individual parts of the building structures and/or for their design. The aim of this article is to establish a calculation procedure for determining the safe design clearance so that the requirements of the legislation are met after implementation. The increase is determined based on a calculation procedure of the limiting geometric deviations that may affect the resulting headroom.","PeriodicalId":45804,"journal":{"name":"Acta Polytechnica","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2022-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42764969","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 Novel Study of Dielectric Properties of Discs Fabricated from Nanopowder of Calcined Clams, Periwinkle, and Oyster Shells 煅烧蛤壳、长春花壳和牡蛎壳纳米粉末制备圆盘介电性能的新研究

IF 0.8

Acta Polytechnica Pub Date : 2022-12-01 DOI: 10.1007/s41050-022-00039-z

S. Etuk, Adebayo Olusakin Adeniran, U. Robert, A. Akankpo, O. Agbasi

引用次数: 0

Oil Supply Chain Integrated Planning based on Holonic Agents and Constraint Programming 基于完整代理和约束规划的石油供应链集成规划

IF 0.8

Acta Polytechnica Pub Date : 2022-11-01 DOI: 10.1007/s41050-022-00038-0

F. Marcellino, Jaime Simão Sichman

引用次数: 0

Experimental study of the torsional effect for yarn break load test of polymeric multifilaments 高分子多长丝断裂载荷试验扭转效应的实验研究

IF 0.8

Acta Polytechnica Pub Date : 2022-10-31 DOI: 10.14311/ap.2022.62.0538

Daniel Magalhães da Cruz, F. Clain, C. E. M. Guilherme

{"title":"Experimental study of the torsional effect for yarn break load test of polymeric multifilaments","authors":"Daniel Magalhães da Cruz, F. Clain, C. E. M. Guilherme","doi":"10.14311/ap.2022.62.0538","DOIUrl":"https://doi.org/10.14311/ap.2022.62.0538","url":null,"abstract":"Polymeric multifilaments have gained a significant interest in recent decades. In the studies of mechanical characteristics, although there are different types of tests, such as rupture, abrasion, creep, impact and fatigue, it can be said that the main mechanical characterisation is the tensile rupture strength (Yarn Break Load, YBL), which also serves as a parameter for other tests. The objective of this work is to evaluate the results of breaking strength under different torsional conditions in polymeric multifilaments and to determine optimal twists for failures. The test were carried out with the following materials: polyamide, polyester, and high modulus polyethylene (HMPE), and for torsional conditions: 0, 20, 40, 60, 120, 240, and 480 turns per metre. As a result, for these torsion groups, curves were obtained for the three materials that present an optimal point of maximum rupture value, which was also experimentally proven. The twist that optimises the breaking strength of HMPE is 38 turns per metre, 56 turns per metre for polyester, and 95 turns per metre for polyamide. The twist groups that exceed the optimal torsion have a deleterious effect on the material, where the multifilament ceases to be homogeneous and starts to create an excessive \"spring effect\". The results found differ from the recommendation of the standard that regulates the YBL test, and thus, a relationship is built between groups of optimal torsion and linear density that provides evidence that the increase in linear density causes the optimal torsion for rupture to also increase, while the standard places a condition of 30 turns per metre for linear densities greater than 2200 dtex, and 60 turns per metre for linear densities less than 2200 dtex. In addition to optimal torsion values, this conclusion is paramount, the test procedure makes a general recommendation that does not optimise the breaking strength.","PeriodicalId":45804,"journal":{"name":"Acta Polytechnica","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2022-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41509711","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: 1

The engineering performance of eco-friendly concretes containing diatomite fly ash and ground granulated blast furnace slag 硅藻土粉煤灰与磨粒矿渣环保型混凝土的工程性能

IF 0.8

Acta Polytechnica Pub Date : 2022-10-31 DOI: 10.14311/ap.2022.62.0505

H. Y. Aruntas, Erkan Yıldız, G. Kaplan

{"title":"The engineering performance of eco-friendly concretes containing diatomite fly ash and ground granulated blast furnace slag","authors":"H. Y. Aruntas, Erkan Yıldız, G. Kaplan","doi":"10.14311/ap.2022.62.0505","DOIUrl":"https://doi.org/10.14311/ap.2022.62.0505","url":null,"abstract":"Approximately 10 % of CO2 is emitted from an ordinary Portland cement production. In cement and concrete production, CO2 emissions can be greatly reduced by using Supplementary Cementitious Materials (SCMs). In addition, the microstructure and durability properties of concrete are greatly improved when silica-rich SCMs are used. In this study, Eco-Friendly concrete design was carried out using three different SCMs. Diatomite, ground granulated blast furnace (GGBFS) and fly ash (FA) were used as the SCM in the concrete mixtures. SCMs were used instead of cement at ratios of 5, 10, 15, and 20 wt %. When diatomite was used at the rate of 20 %, the standard consistency water increased 1.7 times as compared to the reference mixture. With the increase in the replacement ratio, the final setting times of the pastes increased. The high active SiO2 content of diatomite shortened the initial setting time and increased the compressive strength. The use of 5 % diatomite reduced the slump value by 57 % as compared to the reference mixture. The slump and Ve-Be tests of GGBFS and FA mixtures showed similar properties to the reference mixture. The 28-day compressive strength of concrete varied between 29.2–34.6 MPa. With the increase in the curing time of the concrete mixtures, up to 50 % improvements were observed in the compressive strength. Especially on the 180th day, a compressive strength of 44.1 MPa was obtained in concrete mixtures with a 10 % replacement ratio. While using the FA in the mixtures improved the abrasion properties, the opposite result was observed in the case of the GGBFS. It was observed that the mixtures with 5 % FA showed the closest properties to the reference mixture. As a result, it was determined that SCMs with different properties could be used in environmentally friendly concrete mixtures by up to a 20 % replacement ratio.","PeriodicalId":45804,"journal":{"name":"Acta Polytechnica","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2022-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48118348","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: 1

Low earth orbit nanosatellite: influence of heat dissipation on passive thermal analysis 近地轨道纳米卫星:散热对被动热分析的影响

IF 0.8

Acta Polytechnica Pub Date : 2022-10-31 DOI: 10.14311/ap.2022.62.0498

A. Akka, F. Benabdelouahab, R. Yerrou

引用次数: 0

Determination of fan design parameters for light-sport aircraft 轻型运动飞机风扇设计参数的确定

IF 0.8

Acta Polytechnica Pub Date : 2022-10-31 DOI: 10.14311/ap.2022.62.0549

J. Klesa

引用次数: 0