Energy analysis of under-floor air distribution (UFAD) system: An office building case study

•The key issue for efficient performance of UFAD system is to ensure the thermal stratification establishment.•The unnecessarily excess air supplied to the room deteriorates the thermal stratification.•Improper UFAD operation increases the fan power and HVAC electric demand.•The proper UFAD system i...

Full description

Saved in:
Bibliographic Details
Published in:Energy conversion and management 2013-09, Vol.73, p.78-85
Main Authors: Alajmi, Ali F., Abou-Ziyan, Hosny Z., El-Amer, Wid
Format: Article
Language:English
Subjects:
Applied sciences
Ceilings
Deterioration
Direct power generation
Energy
Energy conservation
Energy distribution
Energy saving
EnergyPlus simulation
Exact sciences and technology
Hot climates
Management
Occupants’ and non-occupants’ areas
Office buildings
Simulation
Stations
Thermal stratification
Under-floor air distribution (UFAD) system
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:•The key issue for efficient performance of UFAD system is to ensure the thermal stratification establishment.•The unnecessarily excess air supplied to the room deteriorates the thermal stratification.•Improper UFAD operation increases the fan power and HVAC electric demand.•The proper UFAD system is typically more efficient than the existed UFAD system with energy savings of about 23–37%.•UFAD system shows over the CBAD system saving by about 37–39% during the peak months and 51% during October. This paper presents the results of an experimental and theoretical investigation to evaluate an under-floor air distribution (UFAD) system existed in an office building working on hot climate. Air temperature a distribution and supply air velocity are measured in two measuring stations; each consists of eight temperature sensors which were installed to measure room air temperatures along zone height. The obtained data shows an inefficient operation of the UFAD system which deteriorates the advantages of energy saving that presumed by UFAD system. The building energy simulation program, EnergyPlus, was used to identify the best setting of UFAD system and compare it with the existed UFAD and the conventional ceiling based air distribution (CBAD) system. The simulation results show that setting of room thermostat at 26°C and supply air temperature at 18°C provides the best efficient UFAD system. Due to improper operation of the tested UFAD system, its actual consumption is found to be higher than the best simulated UFAD by 23–37% during July to October. Also, the simulation results show that the HVAC demand of UFAD is lower than CBAD by 37–39% during July–September and 51% in October.
ISSN:0196-8904
1879-2227
DOI:10.1016/j.enconman.2013.04.003