The International                        UPDATED 28th May 2010
Journal of Ventilation
Published Quarterly www.ijovent.org.uk          Buy Journal  Online 

June 2010 Edition of the IJV now Published

IAQVEC 2010 The 7th International Conference on Indoor Air Quality and Energy Conservation in Buildings

August 15 - 18 2010  Syracuse, New York, USA

Paper 3
Experimental Evaluation of Combined DCV and Economizer Cycle using a FLC Variable Air Volume (VAV) System

R. Karunakaran¹, R.Parameshwaran¹, S. Iniyan¹ , Anand A. Samuel²

¹Department of Mechanical Engineering, Anna University , Chennai-25, India
²Vellore Institute of Technology , Deemed University, Vellore , India

Abstract

A healthy indoor environment with sufficient fresh air is a prerequisite for the well-being and high productivity of building occupants. Carbon dioxide (CO₂) based Demand Controlled Ventilation (DCV) optimizes and resolves the traditional conflict between reducing ventilation to save energy while maintaining adequate ventilation for air quality. Therefore, in conditioned spaces where occupancy levels vary, CO₂ based DCV can prove to be an energy efficient method for meeting ventilation needs while maintaining good IAQ.  Furthermore, an economizer cycle can be used to save cooling energy. This design scheme takes advantage of cool weather conditions to supplement or satisfy the cooling load. When a Proportional-Integral-Derivative (PID) controller is used, it can respond only to linear variations using single input and single output operations. This can be improved by using a Fuzzy Logic Controller (FLC). This paper deals with the energy savings in a VAV air conditioning system achieved by combining DCV with an air conditioning economizer cycle incorporating FLC. The CO₂ concentration and outside temperature are taken as input and damper angle as output for the FLC. Both laboratory measurements and simulations were made. Simulation was undertaken using MATLAB-Simulink.  The potential energy savings of DCV combined with a temperature economizer cycle is in the range of 28% to 79% for VAV systems and 19% to 42% for CAV systems. The Indoor Air Quality (IAQ) is also maintained. An experimental test rig was developed and used to verify the performance of the system. This experimental work has been conducted to obtain the system’s response for design outdoor conditions.

Key words:  demand controlled ventilation, DCV, fuzzy logic controller, indoor air quality, IAQ, economizer cycle, laboratory measurements, simulations, energy savings.

 References

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Contents

Paper 1

Indoor Air Quality in Fifty Residences in Athens : Santamouris, M., Argiroudis, K., Georgiou, M., Livada, I. , Doukas, P., Assimakopoulos, M.N., Sfakianaki, A., Pavlou,  K., Geros V. and Papaglastra, M.

Paper 2

Variable Air Volume-Flow Systems - A Possible Way to Reduce Energy Use in the Swedish Dairy Industry: Rohdin, P. and Moshfegh, B.  

Paper 3

Experimental Evaluation of Combined DCV and Economizer Cycle Using a FLC Variable Air Volume (VAV) System: Karunakaran, R., Parameshwaran, R., Iniyan, S. and Anand A. Samuel  

Paper 4

Effects of Nozzle Geometry on the Air Flow Jet and Temperature Distribution in an Enclosed Space: Khan, M.I.  

Paper 5

Automatic Ventilation Control of Trickle Ventilators: Ridley, I. , Davies, M., Booth, W., Judd, C., Oreszczyn, T. and Mumovic, D.  

Paper 6

Minimum Outdoor Air Supply for Radon in High Rise Residential Buildings - Natural Ventilation v Air-Conditioning Unit: Lam, K.S., Chan, E.H.W., Chan, D.W.T., Fung, W.Y., Law, K.C. and Tai, C.T.

Paper 7

Measurement and Prediction of Aerodynamic Stability of an Axial-Flow Ventilation Fan near the Stall Condition: Cao, R. and Hu, J.  

Paper 8

Natural and Mixed Ventilation Design via CFD and Architectural Modelling: Todorovic, M., Ecim, O., Marjanovic, A. and Randjelovic, I.