Dentro do conceito de "Edifício Inteligente", que tem como objetivo a otimização da infra-estrutura física e do ambiente em relação a aspectos de produtividade e comportamentais, este trabalho apresenta uma metodologia para modelagem e simulação de estratégias de gerenciamento de sistemas de ar condicionado onde focaliza-se a integração do ar condicionado com os demais sistemas de um edifício. Para tanto introduz-se uma abordagem híbrida onde são considerados aspectos de Sistemas a Eventos Discretos e de Sistemas de Variáveis Contínuas. Como estudo de caso apresenta-se a modelagem do sistema de ar condicionado do Prédio dos Ambulatórios do Hospital das Clínicas da Faculdade de Medicina de São Paulo, para o qual se aplica o método proposto para análise do tratamento de perturbações no sistema de ar condicionado resultantes de variações da carga térmica. / Considering "Intelligent Buildings", which have as one of its purpose to improve its structure and environment in order maximise the effectiveness of its occupants, this work introduce a methodology for modelling and simulation of HVAC systems. The focus is on the integration of the HVAC system with other building systems. A hybrid approach is introduced to consider both discrete and continuous aspects. As case study, we present the models for the Ambulatory Building of Hospital of the Medical School of São Paulo University. Particularly, the proposed methodology is used to analyse if the response of the HVAC system to thermal load variations can be enhanced, improving the thermal comfort, when integration between systems is considered.

This thesis analyses a specific type of energy usage system, “energy usage in hotels”, and how this system behaves. In order to evaluate the current state of energy use in hotels, an energy audit questionnaire was developed and conducted among 31,5% of hotels on the Adriatic coast. The energy audit was used as a tool to set a benchmark for energy consumption in hotels and to identify opportunities for increased energy efficiency measures in HVAC systems. The analysis has shown that the average energy consumption in hotels on the Adriatic coast is in the range of 159 to 180 kWh/m2 and 162 to 225 kWh/m2 for seasonal and non seasonal hotels respectively. In order to establish a relationship between different independent variables in the hotels (total floor area and number of rooms) and dependent variables, such as electricity and oil consumption, mathematical statistical methods, such as correlation and regression analysis, were implemented. The objective of this thesis was also to develop - from an energy, environmental and economical points of view - a methodology for the design and retrofit of HVAC systems in the hotels on the Adriatic coast. The methodology named HOTECO is based on a system thinking approach. With respect to the technological aspects, the first step was to analyse conventional HVAC system designs and to compare it with the three most promising alternative HVAC systems utilizing renewable energy sources for a typical hotel. Computer modelling in TRNSYS was used to assess energy consumption. TRNSYS software has been used for simulations for a number of years, is internationally recognized, and has been validated and verified. It was concluded that energy and environmental savings in hotels on the Adriatic coast could be achieved using readily available technologies. The HOTECO methodology also demonstrated a framework that supports decision making iv regarding system selection and operational strategies to limit environmental impact from HVAC systems in hotels. Four scenarios for energy consumption in hotels on the Adriatic coast with regards to current state of energy systems and improved retrofit solutions utilizing renewable energy source were given. / QC 20100929

Udržovaní vnitřních klimatických podmínek tak, aby byly v souladu s tepelným komfortem lidí, je klíčovou otázkou pro řízení systémů vytápění, větrání a klimatizace (HVAC systémy). Počítačové modelování nabízí virtuální prostředí pro simulaci vnitřních i vnějších podmínek a s jeho pomocí je možné navrhnout řešení pro řízení technických zařízení budov. Tento proces vyžaduje pochopení těchto prostředí z fyzikálního a matematického hlediska tak, aby bylo možné fyzikální procesy daných prostředí prezentovat pomocí vztahů a rovnic odrážejících jejích různé parametry. Simulační proces dále nabízí možnost popsat interakci mezi těmito modely a jejich chování v čase, dává výchozí reprezentace těchto prostředí, a umožňuje pochopení jejich chování před přenosem těchto modelů do reálných aplikací. Simulace umožnuje respektovat, a ovlivňovat jejích chování přes kontrolu navržených modelů. MATLAB/SIMULINK software má pokročilé schopnosti pro simulace systémů HVAC, a to vytvořením širokého pracovního prostředí pro designéry v závislosti na vývoji matematických modelů a jejích simulace pomocí SIMULINK, aby výsledky mohly být slučitelné s požadovanými výstupy. Tato dizertační práce se zaměřuje na proces modelování vnitřního prostředí v budovách, aby bylo možné pochopit chování klíčových parametrů, které mají vliv na tepelnou pohodu obyvatel či uživatelů, matematické modely vnitřního prostředí posluchárny byly navržené speciálně pro tři základní parametry: koncentrace oxidu uhličitého, teplota vzduchu a relativní vlhkost. Změny chování těchto parametrů v průběhu času jsou simulovány a poté strategie kontroly návrhu těchto parametrů může je udržet ve vhodných rozmezích komfortních pro obyvatele či uživatele, i když změny venkovního klimatu, tepelné a hmotnostní zatíží interiér. Pomocí matematických metod, některé optimalizační metody byly navrženy za účelem snížení spotřeby energie bez vlivu na mezní hodnoty těchto parametrů. Proces validace modelu se provádí porovnáním výsledků s reálnými výstupy monitoringu Honeywell Enterprise Buildings Integrator systémem (EBI) nainstalován v areálu univerzity.

Business dynamics have generally been driven by the ability to create and provide value to customers. Value has evolved over time having meanings from merely price to something that actually creates a competitive advantage. Nevertheless, with the fast change in market conditions, it has become relevant to understand value, how it is originated, how customers perceive it and strategies to delineate it in order to fulfil customer needs in frontier technology environments. This thesis aims to research on how value is perceived in indoor air quality and heating, ventilating and air conditioning technologies, what customers look for and what the drivers are to originate value. The study is supported in empirical data obtained through four semi-structured interviews from customers with experience in these fields working in companies in Europe. After the research, the findings in terms of value entail several factors. Customers approach value by means of performance, however, at the same time this represents a constraint since it is important to balance performance over price. The value promise is also key to comply with customer expectations and current regulations in place. Moreover, due to the fact that locations are different and the type of buildings too, flexibility is another way to adopt value especially because these technologies are expected to have long lifespans and hence, it is important to consider changes in the future. The results also suggest that sustainable value can be found, improving people’s health, reducing environmental impacts and creating key partnerships corresponding to the triple bottom line of sustainability. Finally, some discussions are given in terms of barriers to create value such as the lack of incentives or low capital to invest, followed by a trend of energy saving systems to optimize and improve current conditions in this market.

High Temperature Cooling, HTC, is a thermal conditioning strategy, which aims to reducemixing and transfer heat losses. Cooling capacity strongly depends on heat transfer coefficientsand offers a great response and several advantages in terms of efficiency and sustainability.Among the advantages, there is evidence that HTC offers an increment of energy efficiency ofHVAC systems, provision of healthier and more comfortable indoor climate and provide widepotentials for the applications of renewable. This principle leads to a higher energy efficiency ofwater-based radiant cooling systems.This paper intends to focus on the research of the thermal capacity and performance of a newalternative. This is where Cooling Radiant Ceiling Panels, CRCP, becomes a major innovationwithin the sector and begin to take on certain relevance. The cooling capacity curve of thisparticular CRCP panels has been only measured in an idealized room environment according toDIN EN 14240. Thus, further studies of this key parameter through climate chamber testingand Computational Fluid Dynamics simulations, CFD, are necessary. CFD particularly focuseson fluids in motion, their behavior and their influences in complex processes such as heat transfer.The fluid motion can be described through fundamental mathematical equations and it isbecoming widely used within the building sector.Two different cases are going to be investigated. The first case will determine the mostoptimal peripheral gap to enhance cooling performance through Natural Convection, NC. Thisstudy states the existence of a peripheral gap around the panels has proven to be inefficientin terms of enhancing natural convection in the climate chamber. The second case is aboutcalculating the cooling capacity as a function of the internal heat loads. The cooling capacity ofthe CRCP panels followed an expected behavior. The R-squared factor of the linear regressionwas found to be 0.986, hence, it does not affect the performance of the CRCP panels dependingon the inclusion of the IHLs.This thesis provides the necessary information for the implementation of CRCP panels anddifferent possible operating environments, including considerations, limitations and recommendationsfor future implementation of this strategy.

This investigation studied the level of knowledge that principals have concerning the maintenance of their schools. A questionnaire was developed to address three research questions. These research questions were: (1) what is the extent that facilities maintenance is an important issue for school principals? (2) in what specific areas of facilities maintenance do principals lack knowledge? and (3) in what specific areas does the lack of facilities maintenance knowledge by principals exceed 30%? A questionnaire was developed to gather data to analyze comparative relationships to the research questions. Data indicated that principals do believe facilities maintenance is an important issue. Reponses to the questionnaire indicated most principals have a general understanding of facilities maintenance in its broadest sense. However, the data supported that most principals lack knowledge concerning the specific facilities maintenance information and issues. Recommendations were made to address the lack of knowledge principals have concerning facilities maintenance. Recommendations were also made for additional research in the area of the principal's knowledge concerning facilities maintenance.

Automatic control techniques have been widely employed in industry to increase efficiency and profitability of the processes. However, reliability on automation increases the susceptibility of the system to faults in major control equipment such as actuators and sensors. This realization has motivated design of frameworks for fault detection and isolation (FDI) and fault tolerant control (FTC). The success of these FDI and FTC mechanisms is contingent on their ability to handle complexities associated with process systems such as nonlinearity, uncertainty, high dimensionality and the resulting effects of the existence of complexity in system structure such as faults that cannot be isolated. Motivated by the above considerations, this thesis considers the problem of fault diagnosis and fault tolerant control for complex process systems. First, an FDI framework is designed that can detect and confine possible locations for faults that cannot be isolated. Next, the problem of simultaneous actuator and sensor fault diagnosis for nonlinear uncertain systems. The key idea is to design FDI filters in a way they account for the impact of uncertainty explicitly. This work then considers the problem of simultaneous fault diagnosis in nonlinear uncertain networked systems. FDI is achieved using a distributed architecture, comprised of a bank of local FDI (LFDI) schemes that communicate with each other. The efficacy of the proposed FDI methodologies is shown via application to a number of chemical process examples. Finally, an integrated framework is proposed for fault diagnosis and fault tolerant control of variable air volume (VAV) boxes, a common component of heating, ventilation and air conditioning (HVAC) systems as an industrial case study of complex systems. The advantages of the proposed framework are diagnosing multiple faults and handling faults in stuck dampers using a safe parking strategy with energy saving capability. / Thesis / Doctor of Philosophy (PhD) / Automation is the key to increase efficiency and profitability of the processes. However, as the level of automation increases, major control equipment are more prone to faults. Thus, fault detection and isolation (FDI) and fault tolerant control (FTC) frameworks are required for fault handling. Fault handling, however, can only be efficiently achieved if the designed FDI and FTC frameworks are able to deal with complexities arising in process systems such as nonlinearity, uncertainty, high dimensionality and the resulting effects of the existence of complexity in system structure such as faults that cannot be isolated. This motivates design of FDI and FTC frameworks for complex process systems. First, FDI frameworks are presented that can diagnose faults in the presence of complexities mentioned above. Then, an integrated framework is designed for diagnosing and handling faults of heating, ventilation and air conditioning (HVAC) systems as an industrial case study of complex process systems.

Au cours des deux dernières décennies, la prise de conscience du changement climatique et des conséquences du réchauffement climatique a incité diverses institutions à prendre de nouvelles directives. Ces directives portent principalement sur le contrôle des émissions des gaz à effet de serre, sur l'utilisation des ressources énergétiques non conventionnelles et l'optimisation de la consommation d'énergie dans les systèmes existants. L'Union européenne a proposé de nombreux projets dans le cadre du 7e PCRD pour réaliser jusqu'à 20% d’économies d'énergie d’ici 2020. En particulier, selon la directive sur l'efficacité énergétique, les bâtiments sont majoritairement responsables de 40% des dépenses énergétiques en Europe et de 36% des émissions de CO2 ; c’est la raison pour laquelle un ensemble d’initiatives européennes dans le cadre du 7ième PCRD favorise l'utilisation de technologie intelligente dans les bâtiments et rationalise les règles existantes. Energy IN TIME est l'un des projets axés sur l'élaboration d'une méthode de contrôle basée sur la simulation intelligente de l'énergie qui permettra de réduire la consommation des bâtiments non résidentiels. Ce mémoire de thèse propose plusieurs solutions novatrices pour réaliser les objectifs du projet mandaté à l'Université de Lorraine. Les solutions développées dans le cadre de ce projet devraient être validées sur différents sites européens de démonstration. Une première partie présente l'analyse détaillée de ces sites de démonstration et leurs contraintes respectives. Un cadre général correspondant à la construction type de ces sites a été élaboré pour simuler leur comportement. Ce cadre de construction de référence sert de banc d'essai pour la validation des solutions proposées dans ce travail de thèse. Sur la base de la conception de la structure de construction de référence, nous présentons une formulation de contrôle économique utilisant un modèle de contrôle prédictif minimisant la consommation d'énergie. Ce contrôle optimal possède des propriétés de contrôle conscientes de la maintenance. En outre, comme les bâtiments sont des systèmes complexes, les occurrences de pannes peuvent entraîner une détérioration de l'efficacité énergétique ainsi que du confort thermique pour les occupants à l'intérieur des bâtiments. Pour résoudre ce problème, nous avons élaboré une stratégie de diagnostic des dysfonctionnements et une stratégie de contrôle adaptatif des défauts basé sur le modèle économique ; les résultats en simulation ont été obtenus sur le bâtiment de référence. En outre, l'application des solutions proposées peut permettre de relever des défis ambitieux en particulier dans le cas de bâtiments à grande échelle. Dans la partie finale de cette thèse, nous nous concentrons sur le contrôle économique des bâtiments à grande échelle en formulant une approche novatrice du contrôle prédictif de mode réparti. Cette formule de contrôle distribué présente de nombreux avantages tels que l'atténuation de la propagation des défauts, la flexibilité dans la maintenance du bâtiment et les stratégies simplifiées de contrôle du plug-and-play. Enfin, une attention particulière est accordée au problème d'estimation des mesures dont le nombre est limité sur des bâtiments à grande échelle. Les techniques d'estimation avancées proposées sont basées sur les méthodologies de l'horizon mobile. Leur efficacité est démontrée sur les systèmes de construction de référence / Since the last two decades, there has been a growing awareness about the climate change and global warming that has instigated several Directorate initiatives from various administrations. These initiatives mainly deal with controlling greenhouse gas emissions, use of non-conventional energy resources and optimization of energy consumption in the existing systems. The European Union has proposed numerous projects under FP7 framework to achieve the energy savings up to 20% by the year 2020. Especially, stated by the Energy Efficiency Directive, buildings are majorly responsible for 40% of energy resources in Europe and 36% of CO2 emission. Hence a class of projects in the FP7 framework promotes the use of smart technology in the buildings and the streamline existing rules. Energy IN TIME is one of the projects focused on developing a Smart Energy Simulation Based Control method which will reduce the energy consumption in the operational stage of existing non-residential buildings. Essentially, this thesis proposes several novel solutions to fulfill the project objectives assigned to the University of Lorraine. The developed solutions under this project should be validated on the demonstration sites from various European locations. We design a general benchmark building framework to emulate the behavior of demonstration sites. This benchmark building framework serves as a test bench for the validation of proposed solutions given in this thesis work. Based on the design of benchmark building layout, we present an economic control formulation using model predictive control minimizing the energy consumption. This optimal control has maintenance-aware control properties. Furthermore, as in buildings, fault occurrences may result in deteriorating the energy efficiency as well as the thermal comfort for the occupants inside the buildings. To address this issue, we design a fault diagnosis and fault adaptive control techniques based on the model predictive control and demonstrate the simulation results on the benchmark building. Moreover, the application of these proposed solutions may face great challenges in case of large-scale buildings. Therefore, in the final part of this thesis, we concentrate on the economic control of large-scale buildings by formulating a novel approach of distributed model predictive control. This distributed control formulation holds numerous advantages such as fault propagation mitigation, flexibility in the building maintenance and simplified plug-and-play control strategies, etc... Finally, a particular attention is paid to the estimation problem under limited measurements in large-scale buildings. The suggested advanced estimation techniques are based on the moving horizon methodologies and are demonstrated on the benchmark building systems

The Facility Manager of a laboratory environment continuously walks a fine line between safe and economical operation of that facility. The primary responsibility of the laboratory is to provide a safe environment for personnel while optimizing the space for experiment. Energy efficiency is not a necessary goal. Laboratories typically require HVAC systems utilizing 100% outside air to protect the occupants. Facilities demanding the basic design requirement of 100% outside air can result in annual energy costs 4 to 5 times greater than that of the typical office building requiring 20 CFM per person. With energy costs typically representing a substantial part of an organizations operating budget is it prudent for facility managers to seek opportunities to reduce these costs. The intent of this research is to show that participation of a knowledgeable Facility Manager, during the initial design phase of a laboratory facility, can result in a finished product capable of easily incorporating a variety of energy efficiency technologies. The scope of this research is limited to smaller chemical laboratories supported with less than 20,000 CFM of comfort air. When the Facility Manager actively participates in the design process for laboratory environments there is potential for increased HVAC energy efficiency. A substantial portion of this research has been conducted from the authors daily experience and responsibility for a small chemical laboratory. Additional data was collected using personal interviews among industry experts and fellow colleagues working in the Atlanta metropolitan area with significant laboratory experience. This research focused on the mechanical systems supporting laboratories as they represent the largest percentage in first costs, energy consumption, and offer the greatest opportunity for energy reduction. The results of this research are intended to provide guidance to Facility Managers to incorporate cost effective energy recovery systems in either new construction or at a future date. The results of this research project the impact of energy consumption in a small chemical laboratory from the hypothetical installation of a customized energy recovery system.

Noise control in the heating, ventilation and air-conditioning (HVAC) systems is one of the critical design parameters in measuring the occupant comfort. The noise generated by air-handling units propagates through the ducts in the axial as well as transverse direction. Noise radiated in the transverse direction from the duct walls excited by the internal sound field is called the breakout noise. An analytical formulation has been developed in this thesis in order to predict the breakout noise by incorporating three-dimensional effects along with the acoustical and structural wave coupling phenomena. The first step in the breakout noise prediction is to calculate the interior acoustic response and flexural vibration displacement of the compliant walls. Dynamic interaction between the internal acoustic subsystem and flexible structural subsystem has been expressed in terms of the modal characteristics of the uncoupled response of the acoustic and structural sub-systems. Solutions of the inhomogeneous wave equation are rearranged in terms of impedance and mobility, and the equations describing the complete system are expressed in terms of matrices, which result in a compact matrix formulation. Examples of the formulation are a rectangular cavity with one flexible wall and a rectangular cavity with four-flexible walls. The formulation is modified to incorporate complex boundary conditions by means of appropriate Green’s functions. It is implemented for flexible wall duct using the modified cavity Green’s function. Another objective of the present investigation is to understand the coupling phenomenon and its effect on the compliant wall vibration displacement. The developed three-dimensional analytical analysis of the breakout noise is convenient to implement on the computer, and also to extend the sub-system level model to the system level model in order to analyze a complex acoustic-structural system for the breakout noise problem. The extent of coupling is calculated using a transfer factor based on the uncoupled natural frequencies of the acoustic and structural subsystems. It is observed from the free vibration analysis that a coupling between the cavity and the flexible panel exists in the vicinity of an uncoupled acoustic natural frequency. If a strong coupling occurs between an acoustic mode and a panel mode, then damping of structural subsystem would control it. The cavity volume changes stiffness of the panel, which in turn affects noise radiation in the stiffness-controlled region. The second step is to calculate the sound power radiated from complaint wall. The wall vibration velocity is a linear combination of the uncoupled flexural modes of the structural subsystem. It is substituted into the Rayleigh integral and Kirchhoff– Helmholtz (KH) integral formulation to predict the sound pressure radiated by the vibrating duct wall. The radiated sound power can be obtained by integrating the acoustic intensity over the surface of the flexible duct wall making use of appropriate expressions for radiation impedance. The radiation impedance terms involve a quadruple integral. Evaluation of this integral is quite complex and poses formidable computational challenges. These have been overcome by means of a co-ordinate transformation. Sound power radiation from flexible walls of the plenum and duct walls has been calculated using an equivalent plate model. Analytical results are corroborated with numerical models. The second part of thesis deals with a one-dimensional model to predict the breakout noise from a thin rectangular duct with different end conditions like anechoic termination, rigid-end termination, and the open-end termination. This model incorporates acoustic reflection effects in the duct internal sound field by using standing wave pattern by means of the transfer matrix approach. A one-dimensional prediction method based on the four-pole parameters has been developed to evaluate the lagged duct performance in terms of the breakout noise reduction. Radiation impedance of a duct is calculated by three different methods: (i) finite line source model (ii) finite cylinder model, and (iii) equivalent plate model based on fundamental bending mode of the duct. It is observed that the proposed model that uses the equivalent plate model for the lagged duct and the line source model for the bare duct is appropriate to predict the transverse insertion loss of the lagging, particularly at the lower frequencies that are of primary interest for reducing the breakout noise of rectangular ducts. The bare duct breakout noise results are compared with those of the corresponding 3-D analytical models. It shows that the one-dimensional model captures the overall mean pattern of breakout noise very well. The third part of the thesis examines the internal acoustic field and thence the transmission loss (TL) of a rectangular expansion chamber, the inlet and outlet of which are situated at arbitrary locations of the chamber; i.e., the sidewall or the face of the chamber. The four-pole parameters have been expressed in terms of an appropriate Green’s function of a rectangular cavity with homogeneous boundary conditions. A transfer matrix formulation has been developed for the yielding-wall rectangular chambers by considering structural-acoustic coupling. It may be combined readily with the transfer matrices of the other constituent elements upstream and downstream in order to compute the overall transmission loss or insertion loss. Wherever applicable, parametric studies have been conducted to evolve the design guidelines for minimizing the breakout noise from the HVAC ducts, plenums and cavities.