cost estimation method for gas turbine in conceptual design phase

Abstract Introduction of new gas turbine machines on market is a complex project that requires optimization of different performance parameters such as power, efficiency, maintenance plan, product cost and life. The ability to control cost and impact on performances and life strongly decreases from conceptual to detailed design phase. Actually, 80 % of product's cost and performances are committed based on decisions made in conceptual design. This Paper describes a systematic procedure to estimate the cost of multiple design alternatives during conceptual design phase, comparing different cross sections for gas turbine solutions. Examples of parametric costing tool for part family will be described, to show the approach that allows to estimate costs in conceptual design phase, when detailed design has not been developed and lack of information is a daily topic. The idea is to be able to read design information of each part from an enhanced cross section and enter parametric costing tool to have a preliminary cost estimation in conceptual phase. Doing that for each part or module present, it will be possible to estimate total cost of the product. The scope is to create an internal database where the whole know-how and best practices are stored. This database can be examined in early program stages, to reduce time to market and avoid pursuing solutions that would not be viable or convenient, in a sort of digital twin approach. Another positive aspect pursued and presented, is the positive impact on engineering productivity, that directly reflects on program development cost

A Computational Framework for Designing Interleaved Workflow and Groupware Tasks

Organizations are adopting a variety of process coordination tools such as groupware and workflow management systems to support seamless process execution and streamline individual and group knowledge worker activities. Such process support systems are being deployed in organizations in an ad hoc manner without any overall guiding process design principles leading to additional costly overheads of systems modeling and software maintenance without the requisite benefits. This paper presents a conceptual framework illustrating a structured approach to organizational process design, providing effective task coordination and information management to address some of the relevant issues. Contributions of the research discussed in this paper include: a) a declarative AI planning based representation formalism to describe both individual and group activities, b) a structured top-down design process that enables the design of group and individual activities in an explicit manner, c) computational procedures to automate the generation of process design alternatives, role assignment to tasks, and support the detailed design of group activities. The feasibility of the integrated representation is evaluated based on extant literature on process models and case studies. The benefits of the formalism are evaluated by prototyping intelligent build-time tools for process design, and utilize the same in the design of processes for tasks such as new product development, requirements analysis, and drug discovery. This paper summarizes the work done so far as well as ongoing work by the author as a part of his doctoral dissertation

Development of an approach and tool to improve the conceptual design process of the wing box structure of low-subsonic transport aircraft

To produce a better airframe design, it is imperative to investigate the problems of design and manufacturing integration early on at the conceptual design stage. A new design approach and support tool is required which will aid the designer in future product development. This is a particular necessity in the current context of increasing complexity and challenging economic situations. The present work focuses on the development of a design approach and design aids for designing metallic wingbox structures of low-subsonic transport aircraft with small wing sweepback angles. Its aims are two-fold: to assist in producing alternative structural concepts, and to capture the effects of new materials and manufacturing processes on weight and cost. It will form the basis for selecting the structural concept at the early stage of the design process. The target users of this design approach and tools are relatively inexperienced structural designers and students. The developed process and tools are quite general in their application as they use stand-alone modules which can be employed separately or jointly with existing techniques and tools used by industry, research centres and academia. A comparison of the result from the developed analytical tools against a detailed study undertaken by an aircraft company on the original configuration was made. It showed stress analysis and sizing results that were within a 10% margin. A case study was performed to investigate the reduction of Direct Operating Cost (DOC) of a turboprop transport aircraft by redesigning the wingbox structure. Weight reductions of wing box structure of 16% were achieved using new configurations and advanced metallic materials. The purchase price of the aircraft could also be reduced through use of cheaper labour and new manufacturing processes. These cost savings, if converted into DOC reductions, are only 0.36% of DOC due to fuel saving and 0.25% of DOC due to manufacturing cost reduction for the wingbox structure only. It is obvious that the overall DOC reduction is the result of the total impact of relative DOC effects due to fuel cost saving, material prices, labour rates, and manufacturing process improvements. Within the range of the calculated parameter values, the overall DOC reductions could be as much as 0.61% relative DOC. It appears that fuel prices, material cost and labour rates give greater impacts on DOC than high speed machining processes. Due to the use of advanced aluminium, maintenance cost is also predicted to be less. It has better fatigue life and fracture toughness than the standard aluminium and therefore will increase the aircraft maintenance periods for inspection and repair due to slower crack damage growth. This cost saving will contribute in reducing the life cycle cost of the aircraft. In addition, the number of crack stoppers could be reduced, therefore minimising weight and manufacturing cost. These benefits however have not been analysed

Application of context knowledge in supporting conceptual design decision making

Conceptual design is the most important phase of the product life cycle as the decisions taken at conceptual design stage affect the downstream phases (manufacture, assembly, use, maintenance, and disposal) in terms of cost, quality and function performed by the product. This research takes a holistic view by incorporating the knowledge related to the whole context (from the viewpoint of product, user, product's life cycle and environment in which the product operates) of a design problem for the consideration of the designer to make an informed decision making at the conceptual design stage. The design context knowledge comprising knowledge from these different viewpoints is formalised and a new model and corresponding computational framework is proposed to support conceptual design decision making using this formalised context knowledge. Using a case study, this paper shows the proof of the concept by selecting one concept among different design alternatives using design context knowledge thereby proactively supporting conceptual design decision making for an informed and effective decision making

Capturing, classification and concept generation for automated maintenance tasks

Maintenance is an efficient and cost effective way to keep the function of the product available during the product lifecycle. Automating maintenance may drive down costs and improve performance time; however capturing the necessary information required to perform certain maintenance tasks and later building automated platforms to undertake them is very difficult. This paper looks at the creation of a novel methodology tasked with firstly the capture and classification of maintenance tasks and finally conceptual design of platforms for automating maintenance

An Ontology for Product-Service Systems

Industries are transforming their business strategy from a product-centric to a more service-centric nature by bundling products and services into integrated solutions to enhance the relationship between their customers. Since Product- Service Systems design research is currently at a rudimentary stage, the development of a robust ontology for this area would be helpful. The advantages of a standardized ontology are that it could help researchers and practitioners to communicate their views without ambiguity and thus encourage the conception and implementation of useful methods and tools. In this paper, an initial structure of a PSS ontology from the design perspective is proposed and evaluated

Integrating IVHM and Asset Design

Integrated Vehicle Health Management (IVHM) describes a set of capabilities that enable effective and efficient maintenance and operation of the target vehicle. It accounts for the collection of data, conducting analysis, and supporting the decision-making process for sustainment and operation. The design of IVHM systems endeavours to account for all causes of failure in a disciplined, systems engineering, manner. With industry striving to reduce through-life cost, IVHM is a powerful tool to give forewarning of impending failure and hence control over the outcome. Benefits have been realised from this approach across a number of different sectors but, hindering our ability to realise further benefit from this maturing technology, is the fact that IVHM is still treated as added on to the design of the asset, rather than being a sub-system in its own right, fully integrated with the asset design. The elevation and integration of IVHM in this way will enable architectures to be chosen that accommodate health ready sub-systems from the supply chain and design trade-offs to be made, to name but two major benefits. Barriers to IVHM being integrated with the asset design are examined in this paper. The paper presents progress in overcoming them, and suggests potential solutions for those that remain. It addresses the IVHM system design from a systems engineering perspective and the integration with the asset design will be described within an industrial design process