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Grant
Agency: Cordis | Branch: FP7 | Program: CP-IP | Phase: EeB.NMP.2011-3 | Award Amount: 9.94M | Year: 2012

The building envelope (roof, faade and basements) is the key element to address in order to achieve the energy efficiency in the retrofitting of buildings, where the faade represent the largest part of the heat transmission surface and includes a number of critical components (like windows, balconies, ventilation units,etc) and thermal bridge phenomena. The present project aims to develop an energy efficient integrated system composed by an innovative concept, built on composite materials, and advanced multifunctional panels with technological modules integrated in the faade for building envelope retrofitting. The following solutions will be developed: - Innovative faade concept for retrofitting based on new industrialized constructive system integrating advanced multifunctional panels, technological modules and installations; allowing personalized configurations for each faade typology, orientation and local climate conditions, always using standardized panels and technological modules. It will be cost effective in service life, with low maintenance, easy assembly and disassembly. - Energy Efficient panels and modules integrated in the faade will include a particular technology for reducing energy demand of the building or for supplying energy by means of RES; two new energy efficient modules will be developed: Advanced Passive Solar Protector and Energy Absorption auto mobile unit, Advanced Passive Solar Collector and Ventilation Module. - A set of flexible, lightweight and cost-effective structural panels, easy to be industrialized and assembled, made of composite materials (FRP - Fibre Reinforced Polymer). The solution will be demonstrated in a real building in Spain, in a region with a continental climate, where extreme conditions in summer up to (>35C) and in winter (<0C), covering the different seasons. The building will be monitored before and after the retrofitting with the new Retrofitting system to evaluate the performance solutions.


Grant
Agency: Cordis | Branch: FP7 | Program: BSG-SME | Phase: SME-2012-1 | Award Amount: 1.30M | Year: 2013

Modular construction is used in housing and residential buildings because it is fast to construct and of high quality. This proposal provides the research necessary to extend two types of modular building systems into high-rise building applications where means of providing stability and in some areas, seismic resistance are very important. In addition, the proposal will lead to quantification of the sustainability benefits and acoustic performance, that affect the use of modular construction in the residential building sector. With this information, it is possible to develop design guidance to support the use of these modular systems and to create new markets in high-rise and mixed use buildings. The research will involve full-scale physical tests on modules and on groups of modules, and supprted by finite element analyses as well as on -site measurements of performance. The tests will cover the basic structural performance of the modules and their connections and in particular, their robustness to removal of supports. This will aslso simulate the loss of support and tying action in seismic events. The structural guidance will be presented in the form of application rules to Eurocode 3. Case studies and architectural information will be presented to support the use of the modular systems in practice. This will extend to building typologies using the developed modular systems. seminars and other dissemination activities will be carried out to exploit the results of this research and to create market awareness.


Srinivasan V.,Advanced Simulation Technologies | Greif D.,A-D Technologies | Basara B.,AVL List GmbH
Quenching Control and Distortion - Proceedings of the 6th International Quenching and Control of Distortion Conference, Including the 4th International Distortion Engineering Conference | Year: 2012

In this article, discussions pertaining to a robust computational methodology to simulate the immersion quenching heat treatment process are presented. Computational Fluid Dynamics (CFD) study carried out using the commercial CFD code AVL FIRE® v2011, performs coupled computations encompassing both the fluid domain, containing the quench bath, and the immersing solid structure(s) through a novel interface coupling procedure, which allows data exchange such as of phase change rates, convection coefficients, heat fluxes etc across the domain boundaries. In the fluid domain, the boiling multiphase flow, triggered by the dipping hot solid part into a sub-cooled liquid bath, is handled using an Eulerian multi-fluid method. The ensuing heat and mass transfer effects are modeled based on the different boiling modes, film or nucleate boiling regime, prevalent in the system. In the solid domain, solutions to the energy equation provide the necessary temperature evolution dynamics. Separate computational domains constructed for the quenched solid part(s) and the fluid (quenchant) flow are numerically coupled at the interface of the solid-fluid boundaries leading to a tightly coupled multi-domain system. The discussed quenching procedure is applied to a wide variety of quenching scenarios involving immersion cooling of trapezoidal blocks, engine cylinder heads and other complex structures. Results in the form of temperature evolution in the solids, volume fraction distribution in the fluid domain are compared with the experimental recordings, wherever available. Elaborate descriptions of the numerical and physical models employed in the procedure are provided. Extended applications of the current modeling procedure are also noted. Copyright © 2012 ASM International® All rights reserved.


Srinivasan V.,Advanced Simulation Technologies | Wang D.M.,Advanced Simulation Technologies
Journal of ASTM International | Year: 2011

In this paper, we discuss the development of a new mass transfer model to simulate the thermal and phase change characteristics encountered by binary mixtures during a flow boiling process. The constructed boiling mass transfer model, based on detailed empirical analysis of the heat transfer coefficients pertinent to binary systems and fully implemented within the commercial computational fluid dynamics code AVL FIRE®, is exercised within a multi-fluid framework along with an interfacial area transport modeling procedure to study the heat and mass transfer characteristics of boiling flows inside a rectangular duct. Turbulence in the fluidic system and those generated by the bubbly flow are treated using an advanced k-ζ-f model. The simulation results, comprising of flow variables such as volume fraction, fluidic velocities, temperature and the resultant heat flux generated on the heated wall section, clearly monitors the suppression in heat transfer coefficients with enhancement in flow convection. Competing mechanisms such as phase change process and turbulent convection are identified to influence the heat transfer characteristics. In particular, the varying influence of the mass transfer effects on the heat flux characteristics with alteration in wall temperature is well demonstrated. For example, under low convection velocities, phase change dominates the heat removal from the wall with distinct bubbly flow activity in the boiling regions, while a considerable reduction in bubble dynamics and the phase change contribution towards heat removal with an increase in convection velocities can be clearly extracted. Comparisons of the predicted heat transfer coefficients for varying wall superheat and varying fluidic velocity indicate a very good agreement with experimental data wherever available. A description of the flow field inclusive of interfacial area and number density distribution is provided. The current model can be easily extended to simulate multi-phase flow in complex systems such as a cooling water jacket for automotive applications. Copyright © 2011 by ASTM International.


Saric S.,Advanced Simulation Technologies | Basara B.,Advanced Simulation Technologies
SAE International Journal of Engines | Year: 2015

The present work improves performance of the wall heat transfer model of Han and Reitz employing advanced turbulence modeling and formulating a compressible wall function in the framework of hybrid wall treatment. Some ambiguities related to the originally published model of Han and Reitz are discussed in order to provide a basis for the present modeling approach. A hybrid heat transfer model formulation relies on the k-ζ-f turbulence model which is capable of capturing turbulent stress anisotropy near wall and predicting heat transfer with more fidelity. The model is validated against spark ignition (SI) engine heat transfer measurements. Predicted wall heat flux evolutions on the cylinder head exhibit very good agreement with the experimental data, being superior to similar numerical predictions available in the published literature. In particular, extension of the flame-wall interaction effects, usually considered only in the first near-wall cell, to some of wall-adjacent cells, is found to be important for capturing evolution of the wall heat fluxes and improving model performance with respect to mesh sensitivity. © 2015 SAE International.


Srinivasan V.,Avl Powertrain Engineering | MingWang D.,Avl Powertrain Engineering | Greif D.,Advanced Simulation Technologies | Suffa M.,Advanced Simulation Technologies
Journal of ASTM International | Year: 2011

In this paper, we present the results of the numerical computations carried out to simulate the direct immersion quenching process of several test pieces such as (1) trapezoidal block, (2) hollow block, and (3) engine-cylinder head using a recently developed and implemented quenching simulation methodology within the commercial computational fluid dynamics code AVL FIREVR v2009. Numerical coupling between the simulation domains, involving the fluid and the solid metal region, are achieved through an AVL code coupling interface (ACCI) feature. While mass, momentum, and energy equations utilizing a multi-fluid framework are employed in the fluid domain, only an energy equation is exercised to establish the variation in the thermal field in the solid region. With this coupled approach, both the phasic effects such as bubble dynamics inclusive of clustering and their disposition, vapor pocket generation in the fluid domain, and the temperature field modification in the solid zone are captured very effectively in a concurrent manner. The results presented in this study include comprehensive descriptions of the flow field information and the temperature pattern in the solid at different time instants. A scrutiny of the registered temperature readings at different monitoring locations with the numerical results generates an overall very good agreement for all the cases presented. The computed information adjudges the presence of intense non-uniformity in the temperature distribution within the solid region which is of grave importance in evaluating the stress and fatigue patterns generated in the quenched object. In summary, the capability of the quenching model in simulating a real-time quenching application process and the efficiency in reducing the overall model size by the application of the ACCI procedure are well demonstrated © 2011 by ASTM International.


Srinivasan V.,Advanced Simulation Technologies
ASME 2011 International Mechanical Engineering Congress and Exposition, IMECE 2011 | Year: 2011

In this paper, the development of a new mass transfer model to simulate the thermal and phase change characteristics encountered by binary mixtures during flow boiling process is discussed. A new boiling mass transfer model based on detailed bubble dynamic effects, inclusive of local bubble shear, drag and buoyancy dynamics, has been developed and full implemented within the commercial CFD code AVL FIRE v2010. In the present study the phasic mass, momentum and energy equations are solved in a segregated fashion in conjunction with an interfacial area transport and a number density equation to study the heat and mass transfer characteristics of binary flow boiling inside a rectangular duct. Turbulence in the fluidic system and those generated by the bubbly flow are treated using an advanced k-ζ-f model. The simulation results comprising of flow variables such as volume fraction, fluidic velocities and temperature and the resultant heat flux generated on the heated wall section clearly monitors the suppression in heat transfer coefficients with enhancement in flow convection. Competing mechanisms such as phase change process and turbulent convection are identified to influence the heat transfer characteristics. In particular, the varying influence of the mass transfer effects on the heat flux characteristics with alteration in wall temperature is well demonstrated. Comparisons of the predicted heat transfer coefficients for varying wall superheat and varying fluidic velocity indicates a very good agreement with experimental data, wherever available. Description of the flow field inclusive of interfacial area and number density distribution is provided. The current model can be easily extended to simulate multiphase flow in complex systems such as a cooling water jacket for automotive applications. Copyright © 2011 by ASME.


Srinivasan V.,Advanced Simulation Technologies
ASME 2011 International Mechanical Engineering Congress and Exposition, IMECE 2011 | Year: 2011

In this article, a fixed-grid finite volume approach to simulate the convection-dominated solidification/melting process is presented. An Eulerian multi - fluid modeling approach is employed to track the phase change interface by obtaining solutions to governing volume fraction, momentum and energy transport equations. The liquid-solid interfacial phase transfer effects are modeled using a novel mass transfer function incorporating the latent heat modification due to the phase change process. The alterations in the local phasic fractions and the resultant cellular latent heat is correctly realized using a source term approach within a homogeneous enthalpy modeling framework. The model fully implemented within the commercial CFD code AVL FIRE® V2010 is tested and validated using a (1) classical 1D Stefan's problem (2) melting of gallium (3) tin solidification scenario. In addition to the mass, momentum and energy solutions, transport of species within multi-component liquids is made possible, thereby allowing means for efficient and accurate coupling between the temperature and concentration fields within the system. Description of the phase change fronts, the local velocity and temperature fields are discussed in detail. Results from the simulations are compared against experimental data wherever available. Discussions pertaining to the applicability of the model and its robustness are elaborated within the article. Copyright © 2011 by ASME.


Srinivasan V.,Advanced Simulation Technologies | Kopun R.,A-D Technologies
American Society of Mechanical Engineers, Fluids Engineering Division (Publication) FEDSM | Year: 2012

In this paper, we discuss the implementation and testing of a novel boiling mass transfer model to simulate the thermal and phase transformation behavior, generated due to boiling of binary mixtures, using the commercial CFD code AVL FIRE® v2011. The phase change model, based on detailed bubble dynamics effects, is solved in conjunction with incompressible phasic momentum, turbulence and energy equations in a segregated fashion, to study the flow boiling process inside a rectangular duct. Full three dimensional validation studies including the effect of flow velocity and exit pressure conditions, acting on a wide range of operating wall (superheat) temperatures, clearly shows the suppression of heat and mass transfer coefficients with enhancement in flow convection. Competing mechanisms such as phase change process and turbulent convection are identified to influence the heat transfer characteristics. In particular, the varying influence of the mass transfer effects on the heat flux characteristics with alteration in wall temperature is well demonstrated. Comparisons of the predicted total heat flux, computed as the sum of the convection and phase change components, indicate a very good agreement with experimental data, wherever available. Description of the flow field inclusive of phasic fraction, temperature and velocity field provides extensive details of the multiphase behavior of the boiling flow. Some preliminary results on the phase change work flow to model heat transfer in cooling jackets, for automotive applications, is also discussed. Copyright © 2012 by ASME.

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