The Energy Performance of Buildings Directivementions that each member states' energyperformance (EP) calculation methodology mayinclude envelope airtightness. In fact, manymember states have included envelopeairtightness in their EP calculation method.Many countries have also specific requirementsfor ductwork airtightness. However, they seemto be unequally successful in achieving a markettransformation. This paper describes themechanisms that have been used in somecountries, with a special focus on success storieswhich could inspire other member states.
Detailed mathematical models of VAV equipment and subsystems have been developed and used tocompose larger DCV systems with a large degree of detail. The models and systems take intoaccount both flow/pressure distribution and thermal/contaminant dynamics. The models have beenvalidated against measurements. A number of detailed simulation cases have been conducted. Theresults show that energy usage depends strongly depends on occupancy, flow rates, chosen setpoints as well as the outdoor temperature.
Since the energy-crisis of the 70’ies, the trend goes to energy-saving constructions, that have strongly changed our way of building. The development of highly insulated houses in combination with manual window-airing leads to problems concerning a good q
Investigations in six car parks were carried out. Measurements of carbon monoxide levels were made during the peak hours to compare the performance of the different types of ventilation systems : the performance is better with a combined supply and exhaust system than the exhaust only system though more energy is consumed.
This paper is a clear presentation of the different available systems to ensure a good thermal comfort : the author starts with passive systems that maintain comfort without an extra energy consumption, carries on with the low-energy consumption systems that allow air refreshment ,
then refreshing floors and cool ceilings and low-speed ventilation are described , he ends with
air-handling devices to be installed in residential or collective housings.
The present paper evaluates indoor thermal environment, cooling efficiency and energy consumption between a floor-based system and a ceiling-based system using a mock-up model in cooling period. The experimental chamber has a UFAC, underfloor air conditioning system and a ceiling-based system. And the experiments are set with practical internal load conditions including occupants, lighting units, and heat sources (office automation equipment). The following were compared and evaluated;
1) the vertical and horizontal temperature distribution,
The values of the normalized concentration in the occupied zone (Cn) in an office space arecalculated by CFD for five different ventilation systems and the minimum ventilation rate which maintains the average concentration in the occupied zone under the regulated value is analyzed. Energy consumptions associated with the change in ventilation rate are analyzed. In this analysis, for most ventilation systems, the value of Cn is around 1.0, but for large circulation flow ventilation systems it changes greatly depending on the supply inlet velocity and temperature.
This paper presents the results of the application of building thermal simulation in the design of anew concert hall and refurbishment of interior spaces in the So Francisco Convent in Coimbra, Portugal. The proposed design uses displacement ventilation in all spaces, mechanically driven in the auditorium and hybrid in the convent rooms. A displacement ventilation model, recently implemented in EnergyPlus, is used to predict energy consumption and thermal comfort.
This paper provides information of energy efficiency potential of Personalised Ventilation (PV) systems used in conjunction with a secondary Mixing Volume (MV) air-conditioning system in the tropics. The energy consumption and the acceptability of PV at selected combinations of indoor ambient temperatures of 26 C and PV air supply temperatures of 20 or 23 C, is compared with that of sole mixing ventilation in which the indoor air temperature was controlled at 23 C.
Arthur Rosenfeld cited a study showing that the huge link between IAQ and productivity in anoffice building and the serious initiative to improve indoor air quality will have a tremendous return. This study attempts to analyze the working spaces with different variances. The chamber measurements in the laboratory constructed in Shu-Te University will be taken, and the numerical simulation using CFD techniques will also be applied. The results from both should be compared. The different inlet layout of HVAC system, especially the UFAD system, and the boundary conditions will be discussed.