• Title, Summary, Keyword: Variable Air Volume

Search Result 91, Processing Time 0.072 seconds

A Study on the Application of VAV/BPFS(Variable-Air-Volume/Bypass Filtration System) for Indoor Air Environment (VAV/BPFS(Variable-Air-Volume/Bypass Filtration System) 의 실내환경 적응에 관한 연구)

  • 최성우
    • Journal of Environmental Science International
    • /
    • v.12 no.12
    • /
    • pp.1235-1243
    • /
    • 2003
  • Under controlled conditions in an environmental chamber, 24 experiments were performed to compare the ability of a Variable-Air-Volume/Bypass Filtration System(VAV/BPFS) to remove indoor pollutants and to conserve energy with the ability of conventional Variable Air Volume(VAV) system. The specific conclusions of this paper were; first, the VAV/BPFS was more efficient than the VAV system in removing particulate matter, TVOC, and target VOCs. The total effective removal rate of PM for the VAV/BPFS was two times as high as that of the VAV system. The total effective removal rate of TVOC for the VAV/BPFS was 20 percent higher than that of the VAV system. Also each target VOC concentration was reduced by using the VAV/BPFS. Second, clean air delivery rate was increased by using VAV/BPFS due to additional filtration rate. Otherwise, the VAV/BPFS decreased outdoor supply air rate above 25 percent relative to the rate of VAV system. Third, total energy consumption by the VAV/BPFS was lower than that of the VAV system during the period with indoor thermal load, occupied time. The energy saving of the VAV/BPFS ranged from 11 to 16 percent. The VAV/BPFS improves indoor air quality more efficiently than the VAV system, and it reduced energy consumption. Retrofitting the VAV system with the VAV/BPFS was easy The use of VAV/BPFS is, therefore, recommended far buildings with VAV system as well as for buildings at designing stage.

Ventilation and energy performance evaluation of the office building with variable air volume system (변풍량시스템이 적용된 사무소건물의 환기 및 에너지성능평가)

  • Kwon, Y.L.;Kwon, S.S.
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
    • /
    • v.11 no.1
    • /
    • pp.100-108
    • /
    • 1999
  • Variable air volume(VAV) system designed for improving interior environmental control has steadily evolved over the last 20 years. Major advantage of VAV system is that VAV technology allows a single system to provide simultaneous heating and cooling without a seasonal changeover. Research is carried out in order to study the influence on the energy consumption and ventilation performance of two kinds of office building with a mixing ventilation system. Data required for performance evaluation in these building is obtained from the central monitoring station and by measurement.

  • PDF

A Study of applying VAV and VWV System to reduce Energy Consumption of Office building (VAV 및 VWV시스템 적용에 따른 업무용 건축물의 에너지저감에 관한 연구)

  • Song, Ji-Yong;Hong, Won-Hwa;Kim, Ji-Yeon;Park, Hyo-Soon
    • KIEAE Journal
    • /
    • v.13 no.1
    • /
    • pp.57-63
    • /
    • 2013
  • Building Energy Efficiency Rating system was enforced in 2001 to enhance spreading high-energy performance and saving buildings. It was only for the new apartments, but expanded to new office buildings in 2010, and moreover, government offices require 1st grade of Building Energy Efficiency Rating system. Green Building Act, which is established to reduce the emissivity of carbon dioxide by reducing building energy consumption, will be enforced in 2013, and new apartments and office buildings will be subjected to it. Henceforward, it will extend to other types of buildings and will be phased in. In general, pumps and fans consume approximately half of the air-conditioning energy consumption, and about a quarter of the total building energy consumption when office buildings have total floor area of more than 10000 square meters. This study analyzed the energy demand when applying VAV(Variable Air Volume) and VWV(Variable Water Volume) System to reduce energy returns of the pumps and the fans by ECO2, which is a computer simulation program used for Building Energy Efficiency Rating system.

Energy Saving Potential and Indoor Air Quality Benefits of Multiple Zone Dedicated Outdoor Air System

  • Lee, Soo-Jin;Jeong, Jae-Weon
    • International Journal of High-Rise Buildings
    • /
    • v.8 no.1
    • /
    • pp.71-82
    • /
    • 2019
  • The purpose of this study is to evaluate the indoor air quality (IAQ) and energy benefits of a dedicated outdoor air system (DOAS) and compare them with a conventional variable air volume (VAV) system. The DOAS is a decoupled system that supplies only outdoor air, while reducing its consumption using an enthalpy wheel. The VAV system supplies air that is mixed outdoor and transferred indoor. The VAV has the issue of unbalanced ventilation in each room in multiple zones because it supplies mixing air. The DOAS does not have this problem because it supplies only outdoor air. That is, the DOAS is a 100% outdoor air system and the VAV is an air conditioning system. The transient simulations of carbon dioxide concentration and energy consumption were performed using a MATLAB program based on the thermal loads from the model predicted by the TRNSYS 18 program. The results indicated that when the air volume is large, such as in summer, the distribution of air is not appropriate in the VAV system. The DOAS however, supplies the outdoor air stably. Moreover, in terms of annual primary energy consumption, the DOAS consumed approximately 40% less energy than the VAV system.

A Study on the State feedback with Integral Control for a Variable Air Volume Unit (가변 풍량 유닛에 대한 적분기를 가진 상태 궤환 제어에 관한 연구)

  • 박세화
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.1 no.2
    • /
    • pp.9-14
    • /
    • 2000
  • State feedback with integral control for a variable air volume(VAV) unit which is recently taken notice of for the energy efficiency and saving in the building is studied to investigate the performance of the digital control methodology for the possible practical application. The digital controller which acquires the targat zone temperature and the air flow rate of the supplied air to the zone controls the opening of the damper in the VAV unit. Simulation results are performed for the conditions including reference changes and external thermal variations. In the simulation. simplified conditioned zone and the damper actuator modelling is considered. and relationships between controller gain Parameters and the system dynamics are investigated.

  • PDF

The Impact of Ventilation Strategies on Indoor Air Pollution: A Comparative Study of HVAC Systems Using a Numerical Model (실내오염물질의 환기기술전략에 따른 영향평가 : 수치적 모델을 이용한 HVAC 시스템의 비교연구)

  • Park, Sung-Woo;Song, Dong-Woong;D.J. Moschandreas
    • Journal of Korean Society for Atmospheric Environment
    • /
    • v.11 no.E
    • /
    • pp.45-54
    • /
    • 1995
  • Indoor air quality models are useful to predict indoor air pollutant concentrations as a function of several indoor factors. Indoor air quality model was developed to evaluate the pollutant removal efficiency of variable-air-volume/bypass filtration system (VAV/BPFS) compared with the conventional variable-air-volume (VAV) system. This model provides relative pollutant removal effectiveness of VAV/BPFS by concentration ratio between the conventional VAV system and VAV/BPFS. The predictions agree closely, from 5 to 10 percent, with the measured values for each energy load. As a results, we recommend the VAV/BPFS is a promising alternative to conventional VAV system because it is capable of reducing indoor air pollutant concentration and maintaining good indoor air quality.

  • PDF

Energy Auditing Using a Building Energy Simulation Program BLDSYM

  • Lee, E.J.;Yoon, J.H.;Kang, Y.H.;Jeon, H.S.
    • Solar Energy
    • /
    • v.15 no.3
    • /
    • pp.53-58
    • /
    • 1995
  • The objectives of this study are to introduce the energy simulation program BLDSYM, to verify the approach, and to demonstrate the energy saving opportunities. A case study model for Hoover Middle School, OK, USA has been introduced as a base case simulation. Air-side variable air volume(VAV) and water-side variable flow hydronic(VFH) system have been recommended, modeled and simulated to quantify the energy savings compared with the base system, which is typically constant air and water flow system. More than 30% of energy savings could be obtained with the optimum variable flow system.

  • PDF

A Study on the Air Flow Control of VAV Terminal Unit in Multi-Zone (멀티존 변풍량 터미널 유닛의 풍량 제어 방안에 관한 연구)

  • Kim, Hyo-Jun;Cho, Young-Hum
    • 한국건축친환경설비학회 논문집
    • /
    • v.11 no.5
    • /
    • pp.440-452
    • /
    • 2017
  • The increasing social interests for energy saving has highlighted the need for more buildings with variable air volume (VAV) systems. In order to control the VAV system at multi-zone, it is essential to control terminal unit installed in each zone. This research proposes control method with ventilation requirement of VAV terminal unit in multi-zone. And the conventional and proposed control algorithms were compared through a TRNSYS simulation program. The proposed VAV terminal unit control method satisfies all the conditions of indoor thermal comfort and indoor air quality. An energy comparison with the conventional control method showed that, the method satisfies not only the indoor thermal comfort and IAQ, but also reduces the energy consumption.

Numerical Simulation of Laminar Reacting Flows Using Unstructured Finite Volume Method With Adaptive Refinement

  • Kang, Sung-Mo;Kim, Hoo-Joong;Kim, Yong-Mo
    • Journal of the Korean Society of Combustion
    • /
    • v.6 no.2
    • /
    • pp.15-22
    • /
    • 2001
  • A pressure-based, unstructured finite volume method has been applied to couple the chemical kinetics and fluid dynamics and to capture effectively and accurately the steep gradient flame field. The pressure-velocity coupling is handled by two methodologies including the pressure-correction algorithm and the projection scheme. A stiff, operator-split projection scheme for the detailed nonequilibrium chemistry has been employed to treat the stiff reaction source terms. The conservative form of the governing equations are integrated over a cell-centered control volume with collocated storage for all transport variables. Computations using detailed chemistry and variable transport properties were performed for two laminar reacting flows: a counterflow hydrogen-air diffusion flame and a lifted methane-air triple flame. Numerical results favorably agree with measurements in terms of the detailed flame structure.

  • PDF

Evaluation of Ventilation System Performance Using Indoor Air Quality Model (실내공기질 모델을 이용한 환기 시스템의 공기 정화 효율성 평가)

  • 최성우
    • Journal of Environmental Health Sciences
    • /
    • v.23 no.4
    • /
    • pp.57-66
    • /
    • 1997
  • Successful energy conservation and good indcfor air quality (IAQ) are highly dependent on ventilation system. Air filtration is a primary solution of indoor air control strategies in terms of reducing energy consumption and improving ihdoor air quality. A conventional system with bypass filter, as it is called variable-air-volume/bypass filtration system (VAV/BPFS), is a variation of the conventional variable air volume (VAV) systems, which is designed to eliminate indoor air pollutant and to save energy. Bypass filtration system equipped with a high-efficiency particulate filter and carbon absorbent provides additional cleaned air into indoor environments and maintain good IAQ for human health. The objectives of this research were to compare the relative total decay rate of indoor air pollutant concentrations, and to develop a mathematical model simulating the performance of VAV/BPFS. All experiments were performed in chamber under the controlled conditions. The specific conclusions of this research are: 1. The VAV/BPFS system is more efficient than the VAV system in removing indoor air pollutant concentration. The total decay rates of aerosol, and total volatile organic compound (TVOC) for the VAV/BPFS system were higher than those of the conventional VAV system. 2. IAQ model predictions of each pollutant agree closely with the measured values. 3. According to IAQ model evaluation, reduction of outdoor supply air results in decreased dilution removal rate and on increased bypass filtration removal rate with the VAV/BPFS. As a results, we recommends the VAV/BPFS as an alternative to conventional VAV systems.

  • PDF