A holistic approach integrating all aspects of building design directly affected by its energy performance is necessary for supporting decision-making throughout the design process. In this work, a ...decision-support methodology for the energy design of buildings is proposed, considering the three dimensions of the concept of sustainability, and adapted to the level of information detail available in the early design stages. The 4 modules composing this methodology are (i) a set of 36 key design variables defining the building design, (ii) a set of 16 indicators covering environmental, economic and user comfort aspects of building performance affected by energy-related design decisions, (iii) a calculation method for the performance indicators composed of 7 simulation models, and (iv) a knowledge base of building elements, energy sources and meteorological data. The methodology is primarily aimed to assist architects and engineers who participate in the design of office buildings in a French context.
•We present an experimental pilot of Latent Heat Thermal Energy Storage (LHTES) system.•We couple a thermal model of the LHTES system with a BPS software package.•We compare experimental measurements ...and numerical simulations to validate co-simulation approach.
Air cooling systems that make use of the energy storage potential of the latent heat of Phase Change Materials (PCMs) are alternatives to conventional air-conditioning units for maintaining indoor comfort in summer in light-weight buildings. However, the functioning of such systems is closely linked to the ambient climatic conditions and to the spatial and energy specifications of the buildings to be cooled. For a better understanding of their performance in situ, a thermal co-simulation of a Latent Heat Thermal Energy Storage (LHTES) system and of an existing wooden building is proposed. The performance of this co-simulation is demonstrated by comparing results with experimental results from tests on a building which incorporates an LHTES system. This performance analysis, conducted using Normalised Mean Bias Error (NMBE) and Coefficient of Variation of the Root Mean Square Error (CV(RMSE)), demonstrates the viability of integrating co-simulation to facilitate the LHTES system design process.
Nowadays, patents are more than an industrial property protection, they constitute a considerable source of information. Several approaches deal with the extraction of pertinent information from ...patents, some of them translate that information into useful knowledge for problem-solving purposes. However, very few methods use a physical approach and a consistent analysis of the main function in the problem definition phase. This paper proposes a new method to inspire designers with ideas and analogous solutions. The objective is to contribute to solve complex technical problems by exploiting knowledge found in patent documents. The method is divided into three sections: problem definition, research and analysis, and innovation. The first two sections use iteratively a knowledge base formed by pertinent keywords related to the problem context, physical keywords from functional decomposition and physical analysis, and technological keywords recovered through patent analysis. In the third section, interesting patents are classified in a structured discovery matrix from the physical phenomena involved which are crossed in accordance with the related techniques found. The method is supported by a physical effects database of energy conversion and by evolution trends of technical systems. A deep offshore biphasic separator illustrates the method.
The aim of this study is to propose a variational method of tolerancing analysis using a multiphysical approach. This method is based on operations on polytopes (Minkowski sum and intersection) and ...can be used to validate geometric specifications, contact specifications and thermomechanical specifications.
The first part describes how thermomechanical strains are integrated into a tolerancing analysis tool, based on operations on polytopes. In the second part correlations are defined between two turbine performance criteria, leakage section and risk of touching, and two geometric conditions respectively.
In the third part, the influence of design choices is described, in particular the influence of the shape of the parts and the behaviour of the joints on the thermomechanical operating regime of the turbine.
Two turbine architectures are considered in relation to the same two performance criteria, and lastly the main turbine architecture results are discussed and future developments are described.
•We propose to define performance criteria to compare turbine architectures.•The performance criteria are the risk of touching and the leakage section.•The comparison process is based on a tolerancing analysis model.•This model integrates variability to the thermomechanical behaviour of the turbine.•This model is a variational model based on operations on polytopes.
In systems design, suitably adapted physical models are required. Different modelling approaches for a solar air collector were studied in this paper. First, a classical model was produced, based on ...a linearization of the conservation of energy equations. Its resolution used traditional matrix methods. In order to improve the possibilities for use in design, the behaviour of the collector was next expressed in terms of efficiency. Lastly, simplified models constructed from the results obtained with the classical linearized model, and explicitly including the design variables of the collector, were proposed. These reduced models were then evaluated in terms of
Parsimony,
Exactness,
Precision and
Specialisation (
PEPS). It was concluded that one of them (D2), using a low number of variables and of equations, is well suited for the design of solar air collector coupled with other sub-systems in more complex devices such as solar kiln with energy storage.
►Classical model of the efficiency of a solar air collector. ►Regression of the results of numerical simulations. ►Simplified and precise model depending on a low number of design parameters.
The overwhelming majority of the work involved in the development of external medical devices, as orthoses, consists in applying the companies’ empirical knowledge. However, this non structured ...method, in some cases, may lead to incomplete, inadequate or low products quality. This fact precludes the patient to use the device for long term and consequently the rehabilitation desired effect promoted by the orthosis is compromised. Based on that, to promote a superior product quality, different knowledge from several domains should be considered and should interact in order to achieve a common goal, during the development stages. Additionally, when the development concerns medical devices, the users’ needs and users’ interface and way to use it gain a major importance. The combination of these different factors is a difficult task and is usually overlooked by the companies. This fact demonstrates the importance of the implementation of a design approach for the development of medical devices, which will permit to plan and structure each stage of the products’ development. According to that, the goal of this study was to develop an innovative design approach for the development of an articulated external medical device (articular orthoses) based on the most significant moments during the device’s usage.
The orthosis is considered a class 1 medical device which often originates from a nonstructured development process. As these devices are mainly developed by small- and medium-sized enterprises, with ...no standard research method, the result can be an unadapted device which may not respond to the user’s needs and which in the short term may be abandoned. One way to solve this problem is to define and apply standard rules and procedures throughout the development/design process. Although methodologies may solve the “empiricism” in orthosis design problems, these design strategies are not applied during orthosis development due to the particularities of this field and the difficulties in linking the required knowledge and the actors that may be present during the orthosis development. The objective of this work is to develop a methodology to structure the orthosis design process that takes into account both the device life cycle and the different stakeholders involved in the design process. A case study was used to validate the proposed methodology. It was applied to the development of an orthosis to treat a specific postural disorder called camptocormia, also known as bent spine syndrome. This disorder is characterized by the anteroflexion of the trunk and especially affects elderly people. Contrary to scoliosis, the characteristics of camptocormia are not permanent, which means that the patient is able to straighten his posture. A postural brace is used to treat this disorder which enables the patient to redress and maintain the correct upright posture of the trunk.
Due to the increasing energy use and greenhouse gas emissions related to HVAC applications in the residential sector, thermal energy storage with phase change materials has caught considerable ...attention in the last years. Their attractive storage capacity can be adapted to meet the energy needs of buildings. In this work, the design process of a prototype of an air-PCM unit is described, and the corresponding experimental tests are detailed. These experiments were carried out on a plus energy house prototype located in the Southwestern France, during the summertime of 2017. The thermal performance of this unit was assessed through indicators such as indoor air temperature, the operating time, and the Discomfort Degree Hours (DDH) within the house. The results suggest that the unit limits the indoor air temperature rise during its operation, keeping the temperature within the thermal comfort and therefore contributing to decreasing the thermal discomfort.
To improve the performance of a helicopter turboshaft engine requires optimising the energy yield of the different components, and more particularly controlling clearance between the tips of the high ...pressure turbine blades and the stator. Dimension-chain tools take into account the manufacturing dispersion of the parts and assembly defects. This ensures the interchangeability of the different components and guarantees that a turbine can carry out different service functions, as the turbine is modelled in infinitely rigid solids. However, this approach does not take thermomechanical effects into account. And yet, the different operating regimes of a helicopter engine make it indispensable that the effects caused by the thermodynamic cycle should be integrated. The aim of this article is to show how using dimension chain and thermomechanical tools can contribute to controlling clearances at the tip of a high pressure turbine blade.
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