Afin de lutter contre les allergies alimentaires, la société pharmaceutique DBV Technologies propose un patch épicutané permettant un traitement efficace, la plateforme Viaskin ®.Pour envisager de nouveaux moyens de production de ce patch, nous avons étudié dans cette thèse le procédé d'aérospray (AS).Pour cela, nous avons développé des modèles numériques des différentes parties spatiales de l'AS.Dans un premier temps, nous étudions le cône de liquide formé à la sortie de buse d'AS. L'approche diphasique est traitée à l'aide de la méthode de champ de phase (dite à interface diffuse), dans laquelle l'équation de Cahn-Hilliard gouverne la fonctionnelle d'interface.Deux régimes principaux sont identifiés : le régime Stationnaire Dynamique, où le cône de liquide est stable, et le régime Transitoire, où sa dynamique est périodique.Dans ce second régime, les résultats du modèle ont montré une évolution discontinue de la période d'oscillation du cône en fonction du débit liquide. Nous avons corrélé ce phénomène avec des oscillations capillaires du cône, et comparé avec succès les résultats des simulations numériques aux résultats expérimentaux.Dans un second temps, la fragmentation du jet de liquide produit par le cône est étudiée numériquement, et comparée aux résultats d'analyses de stabilité linéaire produites dans la littérature. Le modèle proposé est une méthode utilisant un maillage mobile, à interface nette.Nous avons montré que la taille des gouttelettes produites variait peu en fonction de la pression de gaz appliquée.L'ensemble des travaux permet de comprendre les phénomènes physiques sous-jacents à l'AS, et à sélectionner dans une optique industrielle les modes optimaux de fonctionnement. / In order to fight against food allergies, the pharmaceutical company DBV Technologies offers an epicutaneous patch for effective treatment, the Viaskin ® platform.To consider new ways of producing this patch, we studied in this thesis the aerospray (AS) process.For this, we have developed numerical models of the different spatial parts of the AS.First, we study the cone of liquid formed at the nozzle exit of AS. The two-phase approach is processed using the so-called diffuse interface phase field method, in which the Cahn-Hilliard equation governs the interface functional.Two main regimes are identified: the Stationary Dynamic flow regime, where the liquid cone is stable, and the Transient regime, where its motion is periodic.In this second regime, the results of the model showed a discontinuous evolution of the oscillation period of the cone as a function of the liquid flow. We have correlated this phenomenon with capillary oscillations of the cone, and successfully compared the results of the numerical simulations to the experimental results.In a second time, the fragmentation of the liquid jet produced by the cone is studied numerically, and compared to the results of linear stability analyzes produced in the literature. The proposed model is a method using a mobile mesh, with a net interface.We have shown that the size of droplets produced varies little according to the applied gas pressure.All of this work improves the understanding of the physical phenomena underlying the AS, and to select from an industrial point of view the optimal modes of operation.

This thesis develops adaptive simulation control techniques that differentiate between competing system configurations. Here, a system is a real world environment under analysis. In this context, proposed modifications to a system denoted by different configurations are evaluated using large-scale hybrid simulation. Adaptive control techniques, using ranking and selection methods, compare the relative worth of competing configurations and use these comparisons to control the number of required simulation observations. Adaptive techniques necessitate embedded statistical computations suitable for the variety of data found in detailed simulations, including hybrid and agent-based simulations. These embedded statistical computations apply efficient sampling methods to collect data from simulations running on a network of workstations. The National Airspace System provides a test case for the application of these techniques to the analysis and design of complex systems, implemented here in the Reconfigurable Flight Simulator, a large-scale hybrid simulation. Implications of these techniques for the use of simulation as a design activity are also presented.

The topic of this dissertation was the use of distributed computing to improve the modeling of the interaction between passenger cars and trucks. The two main focus areas were the development of a methodology to combine microscopic traffic simulation programs with driving simulator programs, and the application of a prototype distributed traffic simulation to study the impact of the length of an impeding vehicle on passing behavior. The methodology was motivated by the need to provide an easier way to create calibrated traffic flows in driving simulations and to capture vehicle behavior within microscopic traffic simulations. The original design for the prototype was to establish a two-way, real time exchange of vehicle data, however problems were encountered that imposed limitations on its development and use. The passing study was motivated by the possible changes in federal truck size and weight regulations and the current inconsistency between the passing sight distance criteria for the design of two lane highways and the marking of no-passing zones. Test drivers made passing maneuvers around impeding vehicles that differed in length and speed. The main effects of the impeding vehicle length were found to be significant for the time and distance in the left lane, and the start and end gap distances. Passing equations were formulated based on the mechanics of the passing maneuver and included behavior variables for calibration. Through a sensitivity analysis, it was shown that increases in vehicle speeds, vehicle length, and gap distance increased the distance traveled in the left lane, while increases in the speed difference and speed gain decreased the distance traveled in the left lane. The passing equations were calibrated using the current AASHTO values and used to predict the impact of increased vehicle lengths on the time and distance in the left lane. The passing equations are valuable for evaluating passing sight distance criteria and observed passing behavior.

No description available.

A computer simulation model, LINKFLOW, has been developed to simulate the movement of water during various water table management practices, such as subsurface drainage, controlled drainage and subirrigation. Water movement is simulated to, or from, a buried tile drainage system through a heterogeneous and anisotropic soil to a zone of water extraction by plant roots and the atmosphere. The computer package links a newly-developed one-dimensional unsaturated ground water flow model to a three-dimensional saturated water flow model that was modified for the linkage and for simulating water flow under different water table management systems and varying climatic conditions. The movement of water is determined for a region of the field and the model can show the effectiveness of a water table management scheme to meet moisture conditions for crop growth for a wide range of soil, topographical, drain layout and weather conditions. LINKFLOW was validated and verified with measurements on subsurface drainage, controlled drainage and subirrigation systems in a corn field in southwestern Quebec. The model provides a powerful tool for the design and evaluation of water table management systems, and it can assist in developing control strategies for efficient management of water resources. LINKFLOW is unique among soil water models for the following features: (1) it can be used to simulate with varying topography; (2) it determines 3-D flows from drains in a heterogeneous, anisotropic soil; (3) it presents results in tabular format, contour map format, or 3-D surface format; and (4) it contains software routines for automated control in subirrigation. The formation of the conceptual model, numerical relations, methods of solution, validation, field verification and examples are presented.

This thesis presents a new way of combining non-linear optimization algorithms and electromagnetic transient (EMT) simulation. In this new combination, a non-linear optimization algorithm utilizes a real-time EMT simulation environment as objective function evaluator. However, as more applications of the off-line EMT simulation software implementation were made, the combination between non-linear optimization algorithms and off-line EMT simulation software revealed new need, which this research work attempts to address. The first need arose from the speed of simulation of the off-line EMT simulation software. With a certain breed of non-linear optimization algorithms, heuristics bases algorithms in particular, a large number of objective function evaluations are required before the termination or convergence criterion in the selected algorithms is satisfied. Sometimes, the number of evaluations as well as the complexity of the simulation case where the objective function is based upon translates into a very long simulation time, which goes beyond the boundary of given resources. This research work attempts to address this simulation timing issue by capitalizing on the real timeness of the simulation environment as well as utilizing the multiple instances of the simulation environment in parallel. The second need arose from the modeling requirement of the off-line EMT simulation software. In order to properly design the necessary objective function evaluator, which is largely a simulation case, a large amount of information needs to be embedded into the case. Under certain circumstances, the necessary information would not be available. Therefore, the simulation case needs to include approximations which may cause compromise in the end result. This limitation becomes more obvious when a real world device such as a commercial controller becomes involved. On the contrary, this limitation can be addressed by the real-time simulation environment because this environment can be directly interfaced with the real world device. In this way, the need for detailed information regarding the device is eliminated. This elimination would enlarge the application of the combination, between the non-linear optimization algorithm and EMT type simulation environment. The effectiveness of the proposed approach is demonstrated by various examples throughout this thesis.

No description available.

No description available.

This thesis presents a new way of combining non-linear optimization algorithms and electromagnetic transient (EMT) simulation. In this new combination, a non-linear optimization algorithm utilizes a real-time EMT simulation environment as objective function evaluator. However, as more applications of the off-line EMT simulation software implementation were made, the combination between non-linear optimization algorithms and off-line EMT simulation software revealed new need, which this research work attempts to address. The first need arose from the speed of simulation of the off-line EMT simulation software. With a certain breed of non-linear optimization algorithms, heuristics bases algorithms in particular, a large number of objective function evaluations are required before the termination or convergence criterion in the selected algorithms is satisfied. Sometimes, the number of evaluations as well as the complexity of the simulation case where the objective function is based upon translates into a very long simulation time, which goes beyond the boundary of given resources. This research work attempts to address this simulation timing issue by capitalizing on the real timeness of the simulation environment as well as utilizing the multiple instances of the simulation environment in parallel. The second need arose from the modeling requirement of the off-line EMT simulation software. In order to properly design the necessary objective function evaluator, which is largely a simulation case, a large amount of information needs to be embedded into the case. Under certain circumstances, the necessary information would not be available. Therefore, the simulation case needs to include approximations which may cause compromise in the end result. This limitation becomes more obvious when a real world device such as a commercial controller becomes involved. On the contrary, this limitation can be addressed by the real-time simulation environment because this environment can be directly interfaced with the real world device. In this way, the need for detailed information regarding the device is eliminated. This elimination would enlarge the application of the combination, between the non-linear optimization algorithm and EMT type simulation environment. The effectiveness of the proposed approach is demonstrated by various examples throughout this thesis.

Digital simulation is a useful tool in many scientific areas. Interactive simulation can provide the user with a better appreciation of a problem area. With the introduction of large scale integrated circuits and in particular the advent of the microprocessor, a large amount of computing power is available at low cost. The aim of this project therefore was to investigate the feasibility of producing a minimum cost, easy to use, interactive digital simulation system. A hardware microcomputer system was constructed to test simulation program concepts and an interactive program was designed and developed for this system. By the use of a set of commands and subsequent interactive dialogue, the program allows the user to enter and perform simulation tasks. The simulation program is unusual in that it does not require a sophisticated operating system or other system programs such as compilers. The program does not require any backup memory devices such as magnetic disc or tape and indeed could be stored in ROM or EPROM. The program is designed to be flexible and extendable and could be easily modified to run with a variety of hardware configurations. The highly interactive nature of the system means that its operation requires very little programming experience. The microcomputer hardware system uses two microprocessors together with specially designed interfaces. One was dedicated to the implementation of the simulation equations, and the other provided an input/output capability including a low cost CRT display.