scholarly journals Study of reinforcement design h-profile of aircraft wing spar

AEROjournal ◽  
2020 ◽  
Vol 16 (2) ◽  
pp. 9-14
Author(s):  
Pavol Pecho ◽  
◽  
Paulína Magdolenová ◽  
Michal Hrúz ◽  
Pavel Kováčik ◽  
...  

In today's world, with ever-increasing safety requirements, there is a growing demand to maintain or reduce production costs. In aviation, in addition to factors like weight and related variables such as resistance to vibration, corrosion, temperature and other are also considered. The task of this paper is to analyse unconventional designs of wing beams with respect to the current requirements of the aviation industry. In the article, the authors analyse the possibilities of design modification either by adding ribs to the profile, or by changing the cross-section of the profile itself. In practice, such design changes would increase weight, production time and finances, but also increase strength and thus safety. All proposed changes were subjected to strength analyses by FEM (Finite element method) computer simulations. The article output is the selection of suitable designs for further observation and experimental verification to ensure comprehensive results for the possibility of implementation in practice. Despite the non-traditional shapes of the proposed wing beam cross-sections, the authors assume that traditional beam shapes will be gradually modified more efficiently.

2015 ◽  
Vol 3 (2) ◽  
pp. 111-122
Author(s):  
Владислав Клочков ◽  
Vladislav Klochkov

The problems of choice of enterprises-recipients of scarce investment resources for the projects of production capacities modernization are considered. The enterprises’ management shows their opportunistic behavior, seeking to request the excess investment amount. Investment projects often do not have economic justification, and new-built modern production facility will not be used efficiently. At the same time, more careful selection of recipients leads to delay in modernization projects’ implementation, reducing the potential savings in production costs. In the paper we propose simple methods of assessing losses arising from restricted rationality of the resources’ dispatchers in the allocation of funds to enterprises that are unable to ensure effective capacity utilization, as well as losses due to the time lag in the decision making. This allows you to develop cost-justified recommendations for improving the processes of decision making. All models are designed to use only available statistical information. The calculations are performed taking into account economic specificities of the aviation industry, but the proposed approaches can be adapted to other industries that are experiencing similar management problems.


2017 ◽  
Vol 56 (5) ◽  
pp. 959-972 ◽  
Author(s):  
Christian Krogh ◽  
Mathias H. Jungersen ◽  
Erik Lund ◽  
Esben Lindgaard

Nafta-Gaz ◽  
2021 ◽  
Vol 77 (3) ◽  
pp. 208-214
Author(s):  
Michał Pajda ◽  
◽  
Wojciech Mazela ◽  

The aim of the work was to present the issue of eco-efficiency, based on the PN-EN ISO 14045:2012 standard in relation to the production of fatty acid methyl esters (FAME). The ecoefficiency analysis takes into account economic and environmental aspects in the improvement of products and processes / technologies. Eco-efficiency considers the product and technology throughout the life cycle, from the construction phase, through use to decommissioning. The impact on the natural environment is assessed on the basis of: consumption of energy, materials, dust and gas emissions, waste and sewage. Total costs include: production costs, raw material costs, costs during the use phase including maintenance, repair and operating costs, product disposal or recycling. The eco-efficiency analysis is helpful in making decisions regarding the selection of a new product or designing a new technology, and enables the selection of the variant that is the most economical and has the least possible impact on the natural environment. These issues are particularly important in the case of biofuels. The rapid growth of their production and the European Union’s policy, which aims to increase the share of energy from renewable sources, cause concerns of many experts regarding the threats related to the production of biofuels, both for the environment and food security. In particular, efforts are made to minimize the amount of waste and residues by implementing the idea of a circular economy. This approach promotes the development of new technologies that are more environmentally friendly. Due to the regulations set out in the RED and RED II Directives, there is a chance that the biofuels will have a less negative impact on the environment. This results from the obligation to certify compliance with the sustainability criteria, which is carried out by voluntary systems recognized by the European Commission, such as the KZR INiG System.


2021 ◽  
Vol 42 (6supl2) ◽  
pp. 4059-4072
Author(s):  
Marcos Paulo Gonçalves de Rezende ◽  
◽  
Paulo Luiz Souza Carneiro ◽  
Riccardo Moretti ◽  
Johnny Iglesias Mendes Araujo ◽  
...  

The selection of animals with lower production costs can be achieved by using feed efficiency and growth curve information. Kleiber ratio (KR) is an alternative option for discriminating against the animals that have the greatest weight gain about their final weight. Alternative feed efficiency and growth curves for ostriches of the African Black (AB) and Red Neck (RN) breeds and their crossbreeds (CB) were investigated using KR and Gompertz equation. Univariate and multivariate analyses were used. The highest adult weight was identified in the RN and CB. AB was more precocious than the RN and CB individuals. Only AB animals reached 75% of their mature weight at one year of age. At 180 days, AB showed better KR. AB was different from the others, mainly for KR at 90 days and 180 days. Considering multivariate analysis, AB animals were different from the others, regardless of sex, mainly for KR at 90 days and KR at 180 days. Other subgroups separated the animals by sex. In a market preferring animals of minor structure (smaller cuts) and greater precocity, it would be suitable to opt for AB. When animals with greater body structure (larger cuts) are desired, males RN and CR is the best option, however, it will be slaughtered with greater age and lower value for KR (may generate a bigger production cost ). It is possible to obtain animals with precocity and high KR, being well represented by the AB breed.


2019 ◽  
Vol 5 (4) ◽  
pp. 73-95
Author(s):  
Nikolai A. Senkin ◽  
Aleksandr S. Filimonov ◽  
Kirill E. Kharitonov ◽  
Vitaliy V. Yakovlev ◽  
Elizaveta O. Bondareva ◽  
...  

As part of student research at the St. Petersburg University of architecture and construction, alternative proposals are being developed for the creation of a circumferential high-speed highway with a total length of 147.2 km. Тhe scheme is proposed in the form of a polygon with HUB in the nodes and consists of three main parts: 1 above-ground (62.6 km), 2 above-water (29.6 km) and 3 surface-underground (55.0 km). The main tracks are located in a four-tube steel beam, each tube of which is organized by the technology of vacuum tube transport with a pressure of 10% of the normal for high-speed passenger trains on a magnetic levitation cushion using a linear traction motor (Maglev system). The rail base of the 1520 mm gauge is located along the entire length of the track, both in parking lots, acceleration and braking zones, and on the main high-speed sections for movement with a maximum speed of 500 km per hour. The main direction of research was the development of load-bearing structures that provide the necessary functionality, reliability and safety of structures. In order to reduce the noise impact on the metropolis, overcome numerous artificial and natural obstacles, improve anti-terrorist protection, the main level of the rail track for the above-ground and above-water structures was adopted at +88.00 in the Baltic elevation system. Calculations of variants with determination of internal forces in elements and movements of nodes with use of the program complex SCAD Office 21.1are executed, when accounting for the full range of loads taking into account dynamic effects and non-linearity. The selection of cross-sections of elements according to the method of limit states according to the current norms is carried out. The advantage of the arch-cable-stayed variant with a span of 360 m in strength, stability, stiffness and vertical size (height of supports) is shown. The continuation of research and design work on this topic should lead to the emergence of a district high-speed transport system at the borders of communication between St. Petersburg and the Leningrad region with passenger traffic, quite comparable to the metro line. Aim: To develop a district high-speed transport system at the borders of St. Petersburg and Leningrad region with passenger traffic comparable to the metro line. Materials and Methods: Using the software package "SCAD Office 21.1", the trestle structures are calculated for the combination of operating loads, forces and influences, including the consideration of dynamic aspects and nonlinearity, as well as the selection of cross-sections of elements by the method of limit states. To determine the optimal trestle structures of high-speed highways, namely high-rise and long-length metal structures supporting the overpass beam, calculations with the selection of cross sections of four variants of cable-stayed systems (arch-cable-stayed; cable-stayed rod with inclined cables and steel lattice pylons; the same, steel pipe-concrete pylons; cable-stayed rod system with suspensions according to the patent US5950543 (A). Results: the results of the trial design adopted arch-cable option with a span of 360 m according to the criterion of metal consumption, the consumption of steel amounted to 20.9 tons per 1 m length of highway. Conclusion: the estimated volume of passenger traffic per day for the four-track high-speed line will be 280 thousand passengers, and 102 million passengers per year, which is quite comparable to this figure for the metro line.


Author(s):  
Ю.В. Брянская ◽  
А.Э. Тен ◽  
Н.Т. Джумагулова ◽  
Г.Н. Громов

В условиях интенсивного развития новых отечественных и зарубежных технологий, материалов и оборудования, применяемых для защиты окружающей природной среды от загрязнений техногенного происхождения, особую актуальность приобретают разработки новых систем отвода и очистки поверхностных сточных вод. Эти системы позволяют использовать последние достижения отраслевой науки и оптимизировать алгоритм выполнения операций и практических приемов их гидравлического расчета. Примером является инновационная система отвода поверхностных сточных вод АСО Qmax, которая относится к открытой системе каналов (лотков) для сбора и отведения поверхностных сточных вод, формирующихся при выпадении атмосферных осадков. Однако широкому применению данного вида конструкций в России препятствует отсутствие методики их гидравлического расчета, в том числе таблиц для подбора сечений (диаметров) каналов, которая бы удовлетворяла требованиям российской нормативно-методической базы проектирования систем отведения поверхностных сточных вод. В этой связи предметом данной статьи явилась оценка гидравлических характеристик трубопроводов, каналов (лотков) системы водоотвода АСО Qmax. Приведены результаты теоретических и экспериментальных исследований гидравлических характеристик системы АСО Qmaxс учетом адаптации для российских условий и нормативных требований, а также обоснование рекомендуемых параметров для их использования. In the context of the intensive development of new domestic and foreign technologies, materials and equipment used to protect the environment from anthropogenic pollution, the development of advanced systems for surface runoff removal and treatment is of special actuality. These systems provide for using the latest achievements of the sectoral science and optimizing the algorithm for performing operations and practical methods for the hydraulic calculations. An example of the innovative surface runoff disposal system is ASO Qmax, that refers to an open system of channels for the collection and disposal of surface runoff formed during precipitation. However, the widespread use of these facilities in Russia is hampered by the lack of a method for the hydraulic calculations, including tables for the selection of cross-sections (diameters) of channels that meet the requirements of the Russian guidelines and regulations for the design of surface runoff disposal systems. In this regard, the subject of this paper is the estimation of the hydraulic characteristics of pipelines, channels of ASO Qmax drainage system. The results of theoretical and experimental studies of the hydraulic characteristics of ASO Qmax system with account of the adaptation for the Russian conditions and regulatory requirements, as well as the justification of the recommended parameters for their use are presented.


Author(s):  
Sebastien Faucou ◽  
Francoise Simonot-Lion ◽  
Yvon Trinquet

The embedded electronic architecture of a modern vehicle is a distributed system composed of several tenths of nodes. The development of these systems relies on a cooperative process involving several partners (carmakers and several suppliers). In such highly competitive domain, three main factors have to be taken into account: the design and production costs, the performance, comfort, and quality of driving, and several stringent safety requirements. In order to fulfill these requirements in such a context, it is vital for the different stakeholders to master the effects of the different sources of complexity. One way to reach this goal is to provide them with a common modeling language capable of representing the system at all its design steps and a common reference architecture in terms of components and organization. This chapter illustrates this approach. It focuses on EAST-ADL, an architecture description language dedicated to the automotive domain. Its links to the reference architecture defined by the AUTOSAR consortium are given. The chapter focuses especially on the ability offered by EAST-ADL to support the validation and verification (V&V) activities in order to fulfill the safety requirements.


Author(s):  
James T. Allison

Modifying the design of an existing system to meet the needs of a new task is a common activity in mechatronic system development. Often engineers seek to meet requirements for the new task via control design changes alone, but in many cases new requirements are impossible to meet using control design only; physical system design modifications must be considered. Plant-Limited Co-Design (PLCD) is a design methodology for meeting new requirements at minimum cost through limited physical system (plant) design changes in concert with control system redesign. The most influential plant changes are identified to narrow the set of candidate plant changes. PLCD provides quantitative evidence to support strategic plant design modification decisions, including tradeoff analyses of redesign cost and requirement violation. In this article the design of a counterbalanced robotic manipulator is used to illustrate successful PLCD application. A baseline system design is obtained that exploits synergy between manipulator passive dynamics and control to minimize energy consumption for a specific pick-and-place task. The baseline design cannot meet requirements for a second pick-and-place task through control design changes alone. A limited set of plant design changes is identified using sensitivity analysis, and the PLCD result meets the new requirements at a cost significantly less than complete system redesign.


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