A Study Of Time Dependent Responses Of A Mechanical Displacement Ventilation Dv System And An Underfloor Air Distribution Ufad System
DOWNLOAD
Download A Study Of Time Dependent Responses Of A Mechanical Displacement Ventilation Dv System And An Underfloor Air Distribution Ufad System PDF/ePub or read online books in Mobi eBooks. Click Download or Read Online button to get A Study Of Time Dependent Responses Of A Mechanical Displacement Ventilation Dv System And An Underfloor Air Distribution Ufad System book now. This website allows unlimited access to, at the time of writing, more than 1.5 million titles, including hundreds of thousands of titles in various foreign languages. If the content not found or just blank you must refresh this page
A Study Of Time Dependent Responses Of A Mechanical Displacement Ventilation Dv System And An Underfloor Air Distribution Ufad System
DOWNLOAD
Author : Jong Keun Yu
language : en
Publisher:
Release Date : 2010
A Study Of Time Dependent Responses Of A Mechanical Displacement Ventilation Dv System And An Underfloor Air Distribution Ufad System written by Jong Keun Yu and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2010 with categories.
As alternative systems for saving cooling energy compared to conventional overhead (OH) air-conditioning systems, mechanical displacement ventilation (DV) systems and underfloor air distribution (UFAD) systems have been widely adopted for commercial buildings. In these alternative systems, supply air is discharged from low momentum diffusers located at lower positions close to the floor in the DV system, and the supply air of the UFAD system is distributed by an underfloor plenum and discharged from floor diffusers. To predict transient vertical temperature responses when the heat source or the ventilation flow rate vary in time, we introduce transient two-layer stratification models of the DV and UFAD systems, non-dimensionalize them by competing the filling box time (Baines & Turner 1969) and the replenishment time in which all the air in the enclosure is replaced by supply air and validate them by laboratory experiments using a salt-water analogy. In various scenarios of the heat source and the ventilation flow rate, the models show a good agreement with the laboratory experiments. Building energy simulation, which predicts cooling and heating demands of a building, has been used for building design, environment, economics, and occupant comfort. EnergyPlus, which is a building energy simulation tools developed by the U.S. Department of Energy, has integrated capability to predict cooling and heating demands as well as the HVAC (heating, ventilation and air conditioning) energy consumption. To evaluate performance of energy savings of UFAD, we developed prototype office buildings adopting OH and UFAD, and the UCSD-UFAD model was used to estimate realistic cooling and heating demands by simulating the stratified temperature profile in a room. In Californian climates, annual electricity consumption of UFAD is always lower than that of OH by up to 20 %, since UFAD has more opportunities to utilize the economizer ``free cooling" compared to OH. For electricity demand reduction of various Demand Response (DR) activities, increasing room set point temperature is the most effective DR activity and UFAD has higher peak demand reduction compared to OH by approximately 6-10 % when the room set point temperature is higher than 26 Celsius.
A Study Of The Thermal Comfort And Ventilation Performance Of An Underfloor Air Distribution System
DOWNLOAD
Author : Jae D. Chang
language : en
Publisher:
Release Date : 2007
A Study Of The Thermal Comfort And Ventilation Performance Of An Underfloor Air Distribution System written by Jae D. Chang and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2007 with categories.
The Fluid Dynamics Of An Underfloor Distribution System
DOWNLOAD
Author : Qing A. Liu
language : en
Publisher:
Release Date : 2006
The Fluid Dynamics Of An Underfloor Distribution System written by Qing A. Liu and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2006 with categories.
This thesis discusses the fluid dynamics of an under floor air distribution (UFAD) ventilation system in which, in contrast to conventional air conditioning systems, cool air is delivered from diffusers in the floor rather than from overhead vents. In order to produce more realistic models of UFAD systems, we extend previous work on a simplified system consisting of a single heat source at floor level and a single cooling diffuser developed by Lin & Linden (2005), to the case of multiple cooling diffusers and a single heat source located at different heights above the floor; of two and more sources of equal or unequal buoyancy fluxes and of a line heat source in a UFAD system. This is an attempt to provide more guidelines to complete the complicated models of UFAD in reality. We carry out experiments in which the heat sources are represented as buoyant point plumes, and the cooling diffusers are modelled using negatively buoyant vertical jets. The radiation from the sun into the system is represented by a line plume attached to a wall. The experiments show that the properties of the system are determined by the entrainment into the plumes and the negatively buoyant jets. In the spirit of Morton, Taylor & Turner (1956), we characterize these entrainment processes by entrainment coefficients, and develop a theoretical model based on layered models of ventilation flows introduced by Linden, Lane-Serff & Smeed (1990). The model predictions are compared with the laboratory experiments, and used to determine the dependence of these parameters on the cooling load, the ventilation rate and the properties of the cooling diffusers. The tank experiments have been compared with full-scale UFAD room tests by non-dimensional scaling analysis, based on which explicit equations were concluded to use in EnergyPlus code.
Displacement Ventilation
DOWNLOAD
Author : Håkon Skistad
language : en
Publisher: Research Studies PressLtd
Release Date : 1994
Displacement Ventilation written by Håkon Skistad and has been published by Research Studies PressLtd this book supported file pdf, txt, epub, kindle and other format this book has been release on 1994 with Technology & Engineering categories.
In displacement ventilation systems, the principle of buoyancy is utilised to remove warm contaminated air from an occupied area. The main driving force is natural convection: instead of attempting to combat the forces of natural convection as in mechanical dilution ventilation, displacement systems supply and exhaust air in such a way as not to interfere with the convection currents set up by the heat sources in a space. Provided that pollution and heat sources are in close proximity, displacement ventilation can give better air quality than dilution ventilation, but good design is necessary to ensure that unacceptable vertical temperature gradients and cold draughts along the floor are avoided.
Underfloor Air Distribution Ufad Design Guide
DOWNLOAD
Author : Fred S. Bauman
language : en
Publisher: Bibliotheca Press
Release Date : 2003
Underfloor Air Distribution Ufad Design Guide written by Fred S. Bauman and has been published by Bibliotheca Press this book supported file pdf, txt, epub, kindle and other format this book has been release on 2003 with Technology & Engineering categories.
This guide is ideal for HVAC design engineers, architects, building owners, facility managers, equipment manufacturers and installers, utility engineers, researchers, and other users of underfloor air distribution (UFAD) technology. UFAD systems are innovative methods for delivering space conditioning in offices and other commercial buildings. Improved Thermal Comfort, Improved Ventilation Efficiency and Indoor Air Quality, Reduced Energy Use and Reduced Life-Cycle Building Costs -- The guide explains these as some of the advantages that UFAD systems have over traditional overhead air distribution systems. This guide provides assistance in the design of UFAD systems that are energy efficient, intelligently operated, and effective in their performance. It also describes important research results that support current thinking on UFAD design and includes an extensive annotated bibliography for those seeking additional detailed information.
Ventilation Effectiveness
DOWNLOAD
Author :
language : en
Publisher:
Release Date : 2004
Ventilation Effectiveness written by and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2004 with Indoor air quality categories.
Building Skins
DOWNLOAD
Author : Christian Schittich
language : en
Publisher: Walter de Gruyter
Release Date : 2012-12-17
Building Skins written by Christian Schittich and has been published by Walter de Gruyter this book supported file pdf, txt, epub, kindle and other format this book has been release on 2012-12-17 with Architecture categories.
The external facades of a building are more than a protective mantle, or an intelligent skin regulating temperature and light, they also determine its very appearance. By unusual choices of materials and the use of complex technology, facades have become increasingly significant in recent years. External surfaces are being perceived as an integral part of the building and are therefore being designed as such. This volume focuses on the wide-ranging aspects of facade design, from the selection and use of materials to the advanced technical possibilities now open to the architect. A wide array of carefully selected international examples show the theory in the practice. All plans, details, and large scale sections of the facades have been researched with the high degree of competence typical of the editorial staff from the review Detail. Expert authors provide the essential information needed to plan and design facades and elucidate on the latest developments in technology and materials.
Displacement Ventilation In Non Industrial Premises
DOWNLOAD
Author : Håkon Skistad
language : en
Publisher: Amer Society of Heating
Release Date : 2004
Displacement Ventilation In Non Industrial Premises written by Håkon Skistad and has been published by Amer Society of Heating this book supported file pdf, txt, epub, kindle and other format this book has been release on 2004 with Technology & Engineering categories.
Building Performance Simulation For Design And Operation
DOWNLOAD
Author : Jan L.M. Hensen
language : en
Publisher: Routledge
Release Date : 2019-04-24
Building Performance Simulation For Design And Operation written by Jan L.M. Hensen and has been published by Routledge this book supported file pdf, txt, epub, kindle and other format this book has been release on 2019-04-24 with Architecture categories.
When used appropriately, building performance simulation has the potential to reduce the environmental impact of the built environment, to improve indoor quality and productivity, as well as to facilitate future innovation and technological progress in construction. Since publication of the first edition of Building Performance Simulation for Design and Operation, the discussion has shifted from a focus on software features to a new agenda, which centres on the effectiveness of building performance simulation in building life cycle processes. This new edition provides a unique and comprehensive overview of building performance simulation for the complete building life cycle from conception to demolition, and from a single building to district level. It contains new chapters on building information modelling, occupant behaviour modelling, urban physics modelling, urban building energy modelling and renewable energy systems modelling. This new edition keeps the same chapter structure throughout including learning objectives, chapter summaries and assignments. Moreover, the book: • Provides unique insights into the techniques of building performance modelling and simulation and their application to performance-based design and operation of buildings and the systems which service them. • Provides readers with the essential concepts of computational support of performance-based design and operation. • Provides examples of how to use building simulation techniques for practical design, management and operation, their limitations and future direction. It is primarily intended for building and systems designers and operators, and postgraduate architectural, environmental or mechanical engineering students.
Ufad Guide
DOWNLOAD
Author : Ashrae
language : en
Publisher: Ashrae
Release Date : 2013
Ufad Guide written by Ashrae and has been published by Ashrae this book supported file pdf, txt, epub, kindle and other format this book has been release on 2013 with Air conditioning categories.
"Guide provides assistance in the design of UFAD systems that are energy efficient, intelligently operated, and effective in their performance. It also describes important research results that support current thinking on UFAD design"--
