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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Patient Room Design that Integrates the Personalized Ventilation System for Cross-Infection Control

Li, Jiaru 11 October 2021 (has links)
Many airborne diseases such as Coronavirus variants are spread from person to person by indoor air movement. This is of particular concern in healthcare environments such as hospitals. There is a significant body of research that suggests that indoor ventilation strategies such as personalized ventilation systems my help reduce the spread of these viruses. While there are studies related to the efficacy of air movement from personalized ventilation, there are very few studies that explore how best to integrate these systems into the design process for hospital patient rooms. This study focuses on how to integrate personalized ventilation (PV) and displacement ventilation (DPV) systems into patient room design. The aims of this study are to first, develop a procedure using the Choosing By Advantages approach to make design decisions related to the implementation for personalized ventilation and displacement ventilation in private and semi-private patient rooms to prevent cross-infection. Secondly, using this approach, design solutions are proposed for patient room layouts with PV and DPV in different locations. The study proposes the best locations and components of the PV and DPV ventilation air supply and exhaust. Further practical models/simulation rooms are required to test the impact of PV systems on patients' and nurses' daily activities. / Master of Science / Many airborne diseases such as Coronavirus variants are spread from person to person by indoor air movement. This is of particular concern in healthcare environments such as hospitals. New personalized ventilation systems place ventilation air directly at the patient bed and consequently can reduce the spread of these viruses by effectively managing in-room air movement. This study explores how best to make design decisions for the implementation of personalized ventilation systems into hospital patient rooms. Applying this decision-making approach, design solutions are proposed that integrate personalized ventilation with commonly used displacement ventilation in patient rooms.
2

Análise experimental da influência de sistema de ventilação personalizada na concentração, dispersão e remoção de partículas expiratórias em cabine de aeronave com sistema de ventilação por mistura e por deslocamento. / Experimental analysis of the influence of customized ventilation system at the concentration, dispersion and removal of expiratory particles in a aircraft cabin with ventilation system by mixing and displacement.

Felix, Victor Barbosa 25 March 2019 (has links)
As pessoas estão cada vez mais viajando de avião e, muitas vezes, em viagens longas. A qualidade do ar torna-se uma questão crucial. Uma forma de melhorar a qualidade do ar e as condições de conforto térmico dentro de uma cabine de aeronave está na utilização de novos sistemas de ventilação personalizada. O objetivo do presente trabalho consiste na análise experimental da influência de um sistema de ventilação personalizada (PV) na concentração, dispersão e remoção de partículas expiratórias em cabine de aeronave com sistema por mistura (MV) e por deslocamento (DV). Os ensaios foram realizados em um mock-up de cabine de aeronave comercial de 12 assentos, com 4 assentos por fileira. O ar foi insuflado na cabine a 18°C pelo sistema MV ou DV, correspondendo a uma leve sensação de frio, e a 24°C pelo sistema personalizado (PV), com vazão de 3,0 l/s, operando no assento próximo à fuselagem e ao corredor, alternadamente. As partículas simulando uma pessoa espirrando foram injetadas em dois pontos no fundo da cabine, respectivamente, no assento próximo à fuselagem e naquele junto do corredor, a 1,10m do piso, que corresponde à região de respiração. Foram medidas velocidades e temperaturas do ar e de partículas ao longo de toda a cabine. Os resultados mostraram que no sistema MV o sistema PV somente influenciou o escoamento do ar e a concentração de partículas no assento onde o sistema PV estava operando, com uma eficiência na remoção de partículas de até 30%. No sistema DV, por sua vez, o sistema PV apresentou eficiência de remoção de até 49% nos assentos em que estava operando. Contudo, o sistema PV pode aumentar em até 32% a concentração de partículas no assento próximo da janela quando o sistema PV estava operando no assento próximo do corredor, no sistema DV. Finalmente, os resultados mostraram resultados mais promissores do sistema PV no sistema MV, com melhoria significativa na remoção de partículas nos assentos onde está operando, sem influenciar negativamente no assento ao lado. / People are increasingly traveling by plane and often on long journeys. Air quality becomes a crucial issue. One way to improve air quality and thermal comfort conditions within an aircraft cabin is to use new personalized ventilation systems. The objective of the present work is the experimental analysis of the influence of a personalized ventilation system (PV) on the concentration, dispersion and removal of expiratory particles in aircraft cabin with mixed system (MV) and displacement (DV). The tests were performed in a 12 seat commercial aircraft cabin mock-up, with 4 seats per row. The air was inflated in the cabin at 18 ° C by the MV or DV system, corresponding to a slight cold sensation, and at 24 ° C by the custom system (PV), with a flow rate of 3.0 l / s, operating in the nearby seat the fuselage and the aisle, alternately. Particles simulating a person sneezing were injected at two points in the bottom of the cockpit, respectively, in the seat near the fuselage and next to the corridor, 1.10m from the floor, which corresponds to the breathing region. Air and particle velocities and temperatures were measured throughout the cabin. The results showed that in the MV system the PV system only influenced the air flow and the concentration of particles in the seat where the PV system was operating, with a particle removal efficiency of up to 30%. The DV system together with PV system showed removal efficiency of up to 49% in the seats in which it was operating. However, the PV system can increase particle concentration in the near-window seat by up to 32% when the PV system was operating on the seat next to the aisle in the DV system. Finally, the results showed more promising results of the PV system in the MV system, with significant improvement in particle removal in the seats where it is operating, without negatively influencing the next seat.
3

Developing a Prototypical Biophilic Localized Natural Airflow Simulator (BLNAS) for a Modular Workstation

Rabab'ah, Ikhlas Oqlah 22 April 2024 (has links)
Doctor of Philosophy / Architects have long been focused on designing eco-friendly buildings, but there's a growing realization that focusing solely on energy efficiency isn't enough. Occupants spend the majority of their time indoors, and the quality of these indoor spaces profoundly impacts their well-being and productivity. Yet, often overlooked, are factors like lighting, air quality, and noise that can significantly affect how occupants feel and perform. With rising urbanization and recent experiences during the COVID-19 pandemic highlighting the importance of indoor environments, there's a renewed emphasis on user-centric design. Biophilic design, which incorporates elements of nature into buildings, has emerged as a promising approach to enhancing occupants' health, wellness, and well-being. Airflow, a critical aspect of biophilic design, plays a key role in creating healthier indoor spaces. This study aims to develop a prototype system that mimics natural airflow patterns indoors to promote occupants' health and well-being. By analyzing weather data, natural airflow features were identified and used to inform the design of a mechanical system. The goal is to create settings that replicate natural airflow patterns in indoor environments. Ultimately, this research lays the groundwork for future studies to explore how such biophilic systems impact occupants' physiological and psychological health. By prioritizing user experience in building design, indoor spaces that not only conserve energy but also enhance the quality of life could be developed.
4

Contaminação aérea em cabines climatizadas: processo de avaliação e análise da influência de sistema de ventilação personalizado. / Airbone contamination in acclimatized cabins: process of evaluation and analysis of the influence of personalized ventilation system.

Conceição, Sandro Tavares 01 June 2012 (has links)
A disseminação de agentes infecciosos em ambientes interiores é um assunto de interesse da sociedade em geral e uma questão de saúde pública, tendo em vista os surtos recentes do vírus SARS, gripe suína, gripe aviária, etc. Em particular, o sistema com suprimento de ar individualizado têm se mostrado eficaz, atuando como barreira contra contaminação cruzada entre ocupantes. Diversas metodologias têm sido aplicadas nesses estudos, tal como gás traçador, geradores de partículas e simulação CFD, muitas vezes sem muito critério, ou com equipamentos e simulações excessivamente complexas. Neste contexto, o objetivo do presente trabalho é desenvolver um processo robusto e com menor complexidade do que os utilizados atualmente para avaliar a dispersão de contaminantes aéreos em ambientes interiores. O processo desenvolvido é aplicado em um estudo de caso onde a influência de um sistema de ventilação personalizado de cabine de aeronave é avaliado sobre a ótica da infecção cruzada. O trabalho contempla a realização de atividades de simulação computacional (CFD) e medições experimentais no ambiente interno de uma cabine de avião (mock-up), onde os campos de velocidade do ar são medidos com Velocimetria por Imagem de Partículas (PIV), partículas entre 2 e 10m são geradas com um gerador de aerossol e contadas com contadores ópticos portáteis. Obteve-se boa correlação entre os resultados numéricos e experimentais para o campo de velocidades e boa concordância qualitativa entre as contagens de partículas no experimento e nas simulações CFD Lagrangeanas. Observou-se, dentre outros aspectos, que a válvula gasper, tal como ensaiada no presente trabalho, contribui para a qualidade do ar na zona de respiração dos ocupantes sentados, promovendo um aumento nas taxas de deposição de partículas nas superfícies internas do mock-up. / The indoor dispersion of infections agents still concern the society, and has become a matter of public health, taken into account the outbreak of SARS in 2003, and the recent cases of influenza strains (H1N1, avian flu, SARS, etc). The use of personalized ventilation has improved the occupants\' air quality on recent evaluations, working as a contaminant spread barrier. Different kinds of methodologies are usually applied for those studies, such as tracer gas, particle generators and CFD simulations, sometimes without adequate criteria, or applying quite complex equipment and simulation methodologies such as transient analysis. Therefore, the main objective of the present work is to develop a robust method, and if possible less complicated than the current ones, to evaluate the dispersion of indoor airborne contaminants. Moreover, one\'s intend to apply the proposed method in a case study to evaluate the influence of a personalized ventilation system to the spread of indoor air contaminants. The study is composed by CFD simulations and experimental measurements inside an aircraft cabin mock-up, where the velocity and temperature field, as well as particle concentration are measured. Particle Image Velocimetry technique is used to analyse air flow velocities. Particles from 2 to 10µm are produced with aerosol generator and injected into the cabine. Finally, particle distributions are measured with hand held optical counters to evaluate air quality at the breathing zone. Good correlation between numerical and experimental results was obtained for velocity field, and adequate qualitative agreement was obtained for concentration field. One\'s conclude the investigated personalized ventilation system has improved the air quality around occupants breathing zone, mainly by increasing the deposition rates at the internal cabin surfaces.
5

Contaminação aérea em cabines climatizadas: processo de avaliação e análise da influência de sistema de ventilação personalizado. / Airbone contamination in acclimatized cabins: process of evaluation and analysis of the influence of personalized ventilation system.

Sandro Tavares Conceição 01 June 2012 (has links)
A disseminação de agentes infecciosos em ambientes interiores é um assunto de interesse da sociedade em geral e uma questão de saúde pública, tendo em vista os surtos recentes do vírus SARS, gripe suína, gripe aviária, etc. Em particular, o sistema com suprimento de ar individualizado têm se mostrado eficaz, atuando como barreira contra contaminação cruzada entre ocupantes. Diversas metodologias têm sido aplicadas nesses estudos, tal como gás traçador, geradores de partículas e simulação CFD, muitas vezes sem muito critério, ou com equipamentos e simulações excessivamente complexas. Neste contexto, o objetivo do presente trabalho é desenvolver um processo robusto e com menor complexidade do que os utilizados atualmente para avaliar a dispersão de contaminantes aéreos em ambientes interiores. O processo desenvolvido é aplicado em um estudo de caso onde a influência de um sistema de ventilação personalizado de cabine de aeronave é avaliado sobre a ótica da infecção cruzada. O trabalho contempla a realização de atividades de simulação computacional (CFD) e medições experimentais no ambiente interno de uma cabine de avião (mock-up), onde os campos de velocidade do ar são medidos com Velocimetria por Imagem de Partículas (PIV), partículas entre 2 e 10m são geradas com um gerador de aerossol e contadas com contadores ópticos portáteis. Obteve-se boa correlação entre os resultados numéricos e experimentais para o campo de velocidades e boa concordância qualitativa entre as contagens de partículas no experimento e nas simulações CFD Lagrangeanas. Observou-se, dentre outros aspectos, que a válvula gasper, tal como ensaiada no presente trabalho, contribui para a qualidade do ar na zona de respiração dos ocupantes sentados, promovendo um aumento nas taxas de deposição de partículas nas superfícies internas do mock-up. / The indoor dispersion of infections agents still concern the society, and has become a matter of public health, taken into account the outbreak of SARS in 2003, and the recent cases of influenza strains (H1N1, avian flu, SARS, etc). The use of personalized ventilation has improved the occupants\' air quality on recent evaluations, working as a contaminant spread barrier. Different kinds of methodologies are usually applied for those studies, such as tracer gas, particle generators and CFD simulations, sometimes without adequate criteria, or applying quite complex equipment and simulation methodologies such as transient analysis. Therefore, the main objective of the present work is to develop a robust method, and if possible less complicated than the current ones, to evaluate the dispersion of indoor airborne contaminants. Moreover, one\'s intend to apply the proposed method in a case study to evaluate the influence of a personalized ventilation system to the spread of indoor air contaminants. The study is composed by CFD simulations and experimental measurements inside an aircraft cabin mock-up, where the velocity and temperature field, as well as particle concentration are measured. Particle Image Velocimetry technique is used to analyse air flow velocities. Particles from 2 to 10µm are produced with aerosol generator and injected into the cabine. Finally, particle distributions are measured with hand held optical counters to evaluate air quality at the breathing zone. Good correlation between numerical and experimental results was obtained for velocity field, and adequate qualitative agreement was obtained for concentration field. One\'s conclude the investigated personalized ventilation system has improved the air quality around occupants breathing zone, mainly by increasing the deposition rates at the internal cabin surfaces.

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