Couplage des transferts de chaleur par convection, chaleur sensible et latente dans un système solaire intégré

Les besoins en chauffage et climatisation ont été fortement réduits dans les constructions dites passives (label PassivHaus en Allemagne ou Minergie en Suisse). Un des moyens d'améliorer encore les performances énergétiques de l'enveloppe est de développer des enveloppes hybrides, utilisées pour la protection, l'isolation, comme capteur d'énergie, capable de la stocker et de la distribuer tout autour de l'enveloppe. Une cellule test a été construite à l'échelle 1:1 et est présentée ici. Il s'agit d'une enceinte de 40m3 délimitée par une enveloppe entièrement ventilée et intégrant des matériaux à changement de phase (MCP). La comparaison des résultats expérimentaux et numériques obtenus grâce à l'outil de simulation développé dans l'environnement TRNSys montre une bonne concordance du modèle pour des configurations en convection forcée. Des améliorations restent à apporter en convection naturelle ainsi que sur les dynamiques de transition de phase des MCP

Annex 65, Long-Term Performance of Super-Insulating-Materials in Building Components and Systems. Report of Subtask I: State of the Art and Case Studies

The objective of this subtask I is to present the main characteristic of SIM (Super Insulating Materials) compared to traditional materials.Two main SIM are considered:- VIP (Vacuum Insulation Panel)- APM (Advanced Porous Materials).Moreover, the present report provides an up-to-date catalogue of commercially available materials & components with technical description and data of each product and information about the application domains and the implementation rules.An overview on all the application areas such as external & internal wall insulation, roofs, floors, ceilings …are investigated through a few case studies.Finally, preliminary results about Life Cycle Assessment of SIM are presented at the end of the report

Annex 65, Long-Term Performance of Super-Insulating-Materials in Building Components and Systems. Report of Subtask III: Practical Applications – Retrofitting at the Building Scale – Field scale

More than 80% of the energy consumption will be influenced by the existing building stock. Accordingly, building renovation has a high priority in many countries. Furthermore, several studies have shown that the most efficient way to curb the energy consumption in the building sector (new & existing) remain the reduction of the heat loss by improving the insulation of the building envelope (roof, floor, wall & windows). All since the first oil crisis in 1973-1974, the national building regulations require improvement of the thermal performance of the building envelope to significantly reduce the energy use for space heating. Following the regulations, the energy efficiency of new buildings has improved. In Europe, targeting to an average U-value close to 0.2 W/m2\ub7K is optimal. Using traditional insulation materials this means an insulation thickness of about 20 cm. Thus, the thickness of internal and/or external insulation layers becomes a major issue of concern for retrofitting projects and even for new building projects in cities. Therefore, there is a growing interest in the so-called super-insulating materials (SIM). The scope of the present work covers two different types of SIMs:• Advanced Porous Materials (APM), where the gaseous heat transfer is hindered significantly by the fine structure in the sub-micrometre range, and• Vacuum Insulation Panels (VIP), where the contribution of gaseous conductivity to the total heat transfer is suppressed by evacuation.For Advanced Porous Materials (APM) one might distinguish between• porous silica e.g. based on fumed silica, and• aerogels.For Vacuum Insulation Panels (VIP) one might distinguish between:• different core materials: fumed silica, glass fibre, PU, EPS, others;• different envelopes: metalized film, aluminium laminate, stainless steel, glass, or combinations;• with or without a getter and/or a desiccant.The objective of this Annex 65 Subtask 3 report is to define the application areas of SIM and to describe the conditions of the intended use of the products. Indeed, it’s clear that the requested performance of the SIM will strongly depend on the temperature, humidity and load conditions. For building applications, storage, handling and implementation requirements are also described. Common and specific numerical calculations will be performed at the building scale to assess the impact of SIM on the performance of the building envelope.SIM was used in almost all building components with different environmental condition (boundary condition) and in different climate zone. The moisture and temperature conditions in building components can cause moisture/temperature induced stresses and the stresses can cause damage in sensitive super insulation material e.g. VIPs. Thus, to convince the conservative market of construction, it needs, in addition to laboratory measurements, real condition/environmental measurements of commercially realized objects (new buildings as well as refurbishments) under several years of operation.The long-term performance of super insulation materials has to be determined based on case studies in field and laboratory. Full scale experiments provide knowledge of practical and technical difficulties as well as data for service life estimation. For certain conclusions to be drawn from the case studies, monitoring is essential. Unfortunately, monitoring is only performed in few case studies. In this report these experiences are gathered and evaluated from a long-term performance perspective.APMs have been commercially successful in the building industry in niche applications typically with space restrictions since the early 2000s. Therefore, over the last years, a number of state-of-the-art reviews have focused on applications of advanced porous materials, such as aerogels, used as thermal insulation in buildings. VIPs, on the other hand, have also been used in other applications than buildings, such as refrigerators and transport boxes. The different applications areas have been identified by numerous researchers. However, in most studies of VIPs available in the literature, it was only the thermal performance of the assembly that was investigated. However, also the moisture performance is important to consider since changes to existing structures will influence the risk for moisture damages.In the Annex, the gathered case studies cover a wider range of SIM i.e. aerogel blankets, AB, (7 case studies), silica-based boards, SB, (3 case studies) and VIP (22 case studies). The aim was to gather information from projects where SIMs were used in different assemblies. Some of the projects have been monitored, i.e. sensors were installed to monitor the temperature, relative humidity or heat flux through the assemblies, while only three have been followed up, i.e. where a third party have analysed the results of the monitoring. The case studies are presented and specific and general conclusions from each application are made.The case studies showed that aerogel blankets are possible to install in up to five layers (50 mm) without too much difficulty. The evaluations showed that the performance of the aerogel blankets was maintained over the evaluation period. For VIPs, it is difficult to evaluate the performance when installed in the wall. In one of the case studies in the report, the external air space made it impossible to identify the different panels by thermography. Only indirect methods, like evaluation of the measured temperatures in the wall, can be used to follow the long-term performance of the panels. In another case study, hybrid insulated district heating pipes were installed at two locations in a district heating system with temperatures up to 90\ub0C. Measurements during the period 2012 to 2015 showed no sign of deterioration of the VIPs and the temperature profile over the pipes was constant. An existing masonry wall was insulated with VIP-foam sandwich (XPS-VIP-XPS). It showed satisfactory and promising performance for a period of six years (2011-present). The analysis of the data obtained from continuous temperature monitoring across each insulation layer indicated the aging of VIP remains insignificant.In the framework of IEA EBC Annex 65 a common simulation-based procedure was introduced with the scope to identify potential critical hygrothermal working conditions of the SIM, which were identified as main drivers of the ageing effect. The study highlights that some physical phenomena (such as thermal bridging effects, the influence of temperature on the thermal conductivity and the decay of performance over time depending on the severity of the boundaryconditions) should be carefully evaluated during the design phase in order to prevent the mismatch between expected/predicted and the actual thermal performance.As general guidelines to mitigate the severity of the operating conditions of VIP, a list of recommendation are in the following summarised:• For the external wall insulation with VIP in solar exposed fa\ue7ade, the adoption of ventilated air layer could dramatically reduce the severity of the VIP operating conditions. Alternatively, light finishing colour are warmly encouraged to mitigate the surface temperature.• The protection of VIP with thin traditional insulation layer is always encouraged.• The application of VIP behind heater determines high value of surface temperature field which could potentially lead to a fast degradation of the panel. A possible solution to mitigate the severity of the boundary conditions could be the coupling of VIP with a radiant barrier, or the protection of VIP with thin insulation layer when it is possible.• In roof application, light colour (cool roof), performant water proof membrane, ventilated airspace and gravel covering layer (flat roof) represent effective solutions to mitigate the severe exposure.• In presence of wall subjected to high driving rain, it is preferable to adopt ventilated fa\ue7ade working as rain-screen to prevent the water absorption.Furthermore, to provide designers, engineers, contractors and builders with guidelines for the applications of vacuum insulation panels (VIPs) and Advanced Porous Materials (APMs) examples are given of methods that may be used to verify the quality and thermal performance of SIMs after installation. A comprehensive account of transport, handling, installation and quality check precures are presented. The main purpose of the descriptions is to promote safe transport, handling and installation. In the case of VIPs the primary issue is that of protecting the panels whereas the main concern for APMs is the safety in handling of the material.During the work of the Annex several questions regarding the long-term performance of SIMs on the building scale have been identified and discussed. Four main challenges were identified:• Knowledge and awareness among designers concerning using SIM• Conservative construction market• Cost versus performance• Long-term performance of SIMsFinally, SIMs for building applications have been developed in the recent decades. Theoretical considerations and first practical tests showed that VIP, especially those with fumed silica core, are expected to fulfil the requirements on durability in building applications for more than 25 years. Both VIPs and APMs have been successfully installed over the past 15 years in buildings. However, real experience from practical applications exceeding 15 years is still lacking, especially when considering third-party monitoring and follow up of demonstrations

Un enfoque integral para propiciar cursos abiertos on line desde la Universidad Nacional de Córdoba

Este proyecto de investigación aplicada da continuidad a las acciones iniciadas en el bienio anterior. Se orienta a la construcción de un prototipo MOOC, en un contexto ya institucionalizado para su desarrollo. Desarrolla acciones de formación de investigadores en tecnologías novedosas como: procesos de digitalización, blockchain, sistemas software, plataformas educativas y herramientas del campo de la Inteligencia Artificial; para coadyuvar a los diferentes enfoques requeridos en el contexto tecnológico actual caracterizado por sus vertiginosos cambios y el aprendizaje colaborativo. Avanza hacia la construcción de propuestas creativas para atender a la articulación entre niveles medio y universitario, por una parte al Ciclo General de Conocimientos Básicos (CGCB) por otra, específicamente en Matemática para Ingeniería en la Universidad Nacional de Córdoba (UNC). Profundiza en el conocimiento del modelo del estudiante, en sus características socioeconómicas, académicas y cognitivas, mediante el uso de Tecnologías Inteligentes de Explotación de la Información (TIEI), no sólo para mejorar los procesos de aprendizaje y evaluación, sino descubrir patrones de comportamiento relevantes para procesos decisionales en la gestión de Educación Superior (ES). Por último, desarrolla actividades interdisciplinarias que posibilitan mejores servicios a la sociedad con la finalidad última de facilitar la apropiación del conocimiento y la tecnología en ES.Eje: Tecnología Informática Aplicada en Educación.Red de Universidades con Carreras en Informátic

Un enfoque integral para propiciar cursos abiertos on line desde la Universidad Nacional de Córdoba

Este proyecto de investigación aplicada da continuidad a las acciones iniciadas en el bienio anterior. Se orienta a la construcción de un prototipo MOOC, en un contexto ya institucionalizado para su desarrollo. Desarrolla acciones de formación de investigadores en tecnologías novedosas como: procesos de digitalización, blockchain, sistemas software, plataformas educativas y herramientas del campo de la Inteligencia Artificial; para coadyuvar a los diferentes enfoques requeridos en el contexto tecnológico actual caracterizado por sus vertiginosos cambios y el aprendizaje colaborativo. Avanza hacia la construcción de propuestas creativas para atender a la articulación entre niveles medio y universitario, por una parte al Ciclo General de Conocimientos Básicos (CGCB) por otra, específicamente en Matemática para Ingeniería en la Universidad Nacional de Córdoba (UNC). Profundiza en el conocimiento del modelo del estudiante, en sus características socioeconómicas, académicas y cognitivas, mediante el uso de Tecnologías Inteligentes de Explotación de la Información (TIEI), no sólo para mejorar los procesos de aprendizaje y evaluación, sino descubrir patrones de comportamiento relevantes para procesos decisionales en la gestión de Educación Superior (ES). Por último, desarrolla actividades interdisciplinarias que posibilitan mejores servicios a la sociedad con la finalidad última de facilitar la apropiación del conocimiento y la tecnología en ES.Eje: Tecnología Informática Aplicada en Educación.Red de Universidades con Carreras en Informátic

Un enfoque integral para propiciar cursos abiertos on line desde la Universidad Nacional de Córdoba

Este proyecto de investigación aplicada da continuidad a las acciones iniciadas en el bienio anterior. Se orienta a la construcción de un prototipo MOOC, en un contexto ya institucionalizado para su desarrollo. Desarrolla acciones de formación de investigadores en tecnologías novedosas como: procesos de digitalización, blockchain, sistemas software, plataformas educativas y herramientas del campo de la Inteligencia Artificial; para coadyuvar a los diferentes enfoques requeridos en el contexto tecnológico actual caracterizado por sus vertiginosos cambios y el aprendizaje colaborativo. Avanza hacia la construcción de propuestas creativas para atender a la articulación entre niveles medio y universitario, por una parte al Ciclo General de Conocimientos Básicos (CGCB) por otra, específicamente en Matemática para Ingeniería en la Universidad Nacional de Córdoba (UNC). Profundiza en el conocimiento del modelo del estudiante, en sus características socioeconómicas, académicas y cognitivas, mediante el uso de Tecnologías Inteligentes de Explotación de la Información (TIEI), no sólo para mejorar los procesos de aprendizaje y evaluación, sino descubrir patrones de comportamiento relevantes para procesos decisionales en la gestión de Educación Superior (ES). Por último, desarrolla actividades interdisciplinarias que posibilitan mejores servicios a la sociedad con la finalidad última de facilitar la apropiación del conocimiento y la tecnología en ES.Eje: Tecnología Informática Aplicada en Educación.Red de Universidades con Carreras en Informátic

Amélioration du confort d'été dans des bâtiments à ossature par ventilation de l'enveloppe et stockage thermique

Depuis quelques années, d'importants efforts ont été réalisés sur l'amélioration de la performance énergétique des bâtiments qui représentent le premier poste de consommation énergétique en France. Les exigences de la nouvelle réglementation thermique 2012 illustrent bien ces évolutions avec une consommation conventionnelle d'énergie primaire comprenant l'ensemble des postes (chauffage, climatisation, éclairage, ventilation, eau chaude sanitaire), déduction faite de l'électricité produite sur place, qui devra être inférieure à 50 kWh.m2.an-1 d'énergie primaire. La réponse à cette nouvelle exigence se fera par l'adoption de technologies constructives conduisant à une consommation pour le chauffage équivalente aux constructions dites passives (environ 15 kWh.m2.an-1) et dont le recours à la climatisation est limité voir inexistant. Il s'agit pour cela de limiter toutes les contributions à l'échauffement du bâtiment et éventuellement de lui adjoindre un système de rafraichissement à coefficient de performance élevé. Après avoir montré par l'exemple qu'un bâtiment à ossature à faible inertie en métropole, par sa capacité de stockage thermique limitée, est prédisposé à des problèmes de surchauffe, nous avons construit cette thèse autour de deux axes d'amélioration, dédiés aux constructions à ossature, que sont : - La limitation des charges solaires transmises au travers de l'enveloppe en faisant appel à une spécificité des constructions à ossature qu'est la présence d'un espace naturellement ventilé en sous-face du parement extérieur que nous utiliserons afin d'extraire une partie des charges solaires incidentes; - Le couplage de ces bâtiments légers à un échangeur air/masse qui contient l'inertie nécessaire au maintien des conditions de confort estivales lorsque la réduction de température nocturne le permet. Basée sur une approche numérique et expérimentale en vrai grandeur et en conditions réelles, nous proposons d'aborder tour à tour chacune de ces stratégies d'amélioration du confort qui trouvent leurs applications aussi bien en climat chaud et sec qu'en climat tropical.Building sector is the most important energy consumer in France, and one of the field where there is the highest potential for improvement. In recent years, building energy consumption has been the subject of continuously up-dated regulations aimed at reducing its impact. As an example, the latest national thermal regulation (RT 2012) makes it compulsory to respect the limits previously introduced by RT 2005 as a voluntary label, corresponding to the definition of guil{Low energy consumption buildings} (BBC); in order to get such a label, a building should have a primary energy consumption lower than 50 kWh.m2.an-1, calculated by making a balance between consumptions (heating, cooling, domestic hot water, lighting, ventilation) and local electricity production. In order to respond to this new requirement, appropriate architectural and technological solutions have to be used. As a results, heating needs should be limited to approximately 15 kWh.m2.an-1 - by improving the building insulation or by adopting passive solar techniques - and summer thermal comfort should be achieved with a minimum primary energy waste. Therefore, internal heat gains and external solar transmission must be limited and, if necessary, low energy cooling systems could be used. In the present work, we firstly studied the case of a low thermal inertia building. The simulation results show that this construction typology is subject to uncomfortable temperature swing. Afterwards, two propositions leading to the improvement of summer thermal comfort were developed. The first, dedicated to warm and humid climates, consists in limiting solar transmission through the wall by using a gap, generally integrated in a timber frame structure, to eliminate part of the absorbed heat by means of natural ventilation. Then, the increase of the building thermal inertia through the association of an air/mass storage system was assessed, which is especially suitable in warm and dry climates. Both propositions were based both on numerical studies and on experimentation performed on a full-scale test rig installed at CSTB (Scientific and Technical Centre for Building research).SAVOIE-SCD - Bib.électronique (730659901) / SudocGRENOBLE1/INP-Bib.électronique (384210012) / SudocGRENOBLE2/3-Bib.électronique (384219901) / SudocSudocFranceF

A simplified numerical method to assess the whole energy performance of residential buildings

International audienceno abstrac

A simplified numerical method to assess the whole energy performance of residential buildings

International audienceno abstrac