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The purpose of this paper is to present the results of the preliminary design and optimization of the air-intake system and the engine nacelle. The work was conducted as…
The purpose of this paper is to present the results of the preliminary design and optimization of the air-intake system and the engine nacelle. The work was conducted as part of an integration process of a turboprop engine in a small aircraft in a tractor configuration.
The preliminary design process was performed using a parametric, interactive design approach. The parametric model of the aircraft was developed using the PARADES™ in-house software. The model assumed a high level of freedom concerning shaping all the components of aircraft important from the point of view of the engine integration. Additionally, the software was used to control the fulfillment of design constraints and to analyze selected geometrical properties. Based on the developed parametric model, the preliminary design was conducted using the interactive design and optimization methodology. Several concepts of the engine integration were investigated in the process. All components of the aircraft propulsion system were designed simultaneously to ensure their compliance with each other.
The concepts of the engine integration were modified according to changes in the design and technological constraints in the preliminary design process. For the most promising configurations, computational fluid dynamics (CFD) computations were conducted using commercial Reynolds-averaged Navier–Stokes solver FLUENT™ (ANSYS). The simulations tested the flow around the nacelle and inside the air-delivery system which consists of the air-intake duct, the foreign-particles separator and the auxiliary ducts delivering air to the cooling and air-conditioning systems. The effect of the working propeller was modeled using the Virtual Blade Model implemented in the FLUENT code. The flow inside the air-intake system was analyzed from the point of view of minimization of pressure losses in the air-intake duct, the quality of air stream delivered to the engine compressor and the effectiveness of the foreign particles separator.
Based on results of the CFD analyses, the final concept of the turboprop engine integration has been chosen.
The presented results of preliminary design process are valuable to achieve the final goal in the ongoing project.
The objective of software development is to produce accurate, efficient, easily maintainable systems which perform reliably and meet the users' needs as effectively as possible. However, this objective is still not being achieved in most installations. During the last ten years many good methodologies for programming have been introduced and it is generally agreed that the use of almost any of these solves most, if not all, of the problems encountered during programming. But methodologies for commercial systems design have not become so well established, although it is generally recognised that many systems are poorly designed and that this causes problems in later development stages and subsequent maintenance. The design problem has been highlighted since programming has improved so much through the use of new techniques.
Examines the conceptual design of robotic assembly systems inconjunction with the analysis and optimization of the product and processdesign. Explains how an integral…
Examines the conceptual design of robotic assembly systems in conjunction with the analysis and optimization of the product and process design. Explains how an integral assembly model is utilised to study the relationships between assembly variables which play a role in each stage of the design process. Outlines the characteristics and benefits of the concentric design process and explains the total productivity concept. Concludes that the integral assembly model, which underlies the concentric design process, provides the opportunity to store product, process and system data and can therefore be considered as a reference model for product development and process planning as well as for the design and analysis of assembly systems.
For me, the human side of work is the most important aspect in any consideration of jobs and organizations. Hospital organizations, for example, are made up of people…
For me, the human side of work is the most important aspect in any consideration of jobs and organizations. Hospital organizations, for example, are made up of people, their jobs are, of course, done by people, and the results of that work are for people — whether they be direct recipients such as patients, or customers; or whether they be the indirect recipients such as the community, or the employees themselves. The dilemma is highlighted by asking, why do we so often separate the effects of work on the humans involved in its production, from the effects on humans as recipients of its end result? I will posit that if work is consciously designed as a meaningful activity for the people involved in its production, then chances are good that its product will also better suit its human users. That is, there is a systemic relationship between the quality of working life and the quality of the product of that work. In so saying however we must likewise acknowledge the importance of the technical requirements of the work — for having meaning to the people involved is not enough. Work that is meaningfully arranged, both for the humans involved in its execution and for its technical requirements, typically results in a higher quality product and, not infrequently, in greater productivity as well. In our experience results are frequently accompanied by lowered absenteeism and turnover and greater feelings of satisfaction with the work activity. Work system design, or socio‐technical system design, is a powerful approach to this human side of work — work that is meaningful in both that human sense, as well as the technical sense.
It is important to provide building performance feedback to the designer as early as possible in the design process. However, many aspects of building performance are…
It is important to provide building performance feedback to the designer as early as possible in the design process. However, many aspects of building performance are significantly affected by the design of the building’s technical systems (e.g., heating, airconditioning), which are typically configured in detail only in the later stages of design. The challenge is thus to find a method to use detailed simulation tools even during the early stages of design when values for many of the variables for the building’s technical systems are not yet available. In this paper, we demonstrate how this problem can be partially solved by use of differential representation for building and technical system, homology‐based automatic mapping of relevant information from the building to the technical system representation, and generative design agents which, with a minimal user‐input, can design and model the technical system. We conclude the paper with illustrative examples of detailed performance analysis of complex buildings and their heating, ventilation, and air‐conditioning systems, performed in early stages of design.
The development of reconfigurable modular production systems is one of the crucial factors for manufacturers to sustain their competitive advantage in areas such as…
The development of reconfigurable modular production systems is one of the crucial factors for manufacturers to sustain their competitive advantage in areas such as precision assembly. To ensure the effective and cost efficient configuration and successive reconfigurations it is of critical importance to involve all stakeholders in the decision‐making process. The reported research is targeting the development of an integrated Web‐enabled decision‐making environment that supports some of the key assembly system engineering stages from user requirement specification to system implementation. The focus is on the design of assembly workstations based on detailed process requirements with a target of developing highly efficient and cost‐effective solutions. The paper presents an application framework for collaborative distributed design supported by domain ontologies and is illustrated using an industrial case study.
To set‐up a specific design procedure for the smart unmanned aerial vehicle (UAV) fuel supply system which has been developed by Korean Aerospace Research Institute, and…
To set‐up a specific design procedure for the smart unmanned aerial vehicle (UAV) fuel supply system which has been developed by Korean Aerospace Research Institute, and to design it preliminarily with the fuel system requirement and target reliabilities.
The fuel system layout and fuel tank were determined through consideration of total fuel volume, fuel flow rate, reliability, weight, centre of gravity, etc. In sizing of components such as booster pumps, jet pumps, piping system, vent subsystem, refuelling and defuelling subsystem, engine fuel flow requirement, pressure loss, component failure rate, weight and centre of gravity were considered. Finally, the reliability analysis of the preliminary designed fuel system was carried out.
According to the reliability analysis and weight estimation results, it was confirmed that the proposed fuel system agreed well with the design specifications and target reliabilities required by the vehicle system.
In current preliminary design phase, the most important consideration is the reliability of the fuel system. Therefore, the weight estimation of the designed fuel system to meet this reliability requirement could not meet partially the system's requirements. In the next design step, the proper fuel system for weight reduction will be performed through an optimization process between weight and reliability.
A specific design procedure components' sizing to meet system requirement target reliability for UAV vertical take‐off/landing was proposed.
Introduces the need for engineering knowledge management tools for storing past solutions and expert knowledge for the design of automatic precision machinery. The design…
Introduces the need for engineering knowledge management tools for storing past solutions and expert knowledge for the design of automatic precision machinery. The design of this type of machine, which is heavily utilised in modern manufacturing industry, is very complex, time‐consuming and potentially expensive. Describes the design and functionality of a novel computer aided rapid prototyping tool named Schemebuilder. The design is traced from its philosophical origins in the “Theory of domains” and how this can be used by the designer with the aid of the computer. The application of this underlining methodology for the design of precision machinery employing feedback control systems is also described. Finally an example is shown for the design of a control system for precise position control of a glass bottle making machine.
It has been suggested that “space and artifacts constitute systems of communication which organizations build up within themselves” (Gagliardi, 1992a, b, p. vi) and…
It has been suggested that “space and artifacts constitute systems of communication which organizations build up within themselves” (Gagliardi, 1992a, b, p. vi) and reflect the cultural life within that organization. This is a study of how the “landscape” of a public library (“Library X”), as an information retrieval system, relates to the values of the people who created it. The efforts here are geared towards understanding the physical instantiation of institutional culture and, more specifically, institutional values as they are reflected through the artifact.