SIMULATION STUDY ON DIRECT FEEDBACK LINEAR (DFL) CONTROL IN VAV AIR-CONDITIONING SYSTEM

The objective of this paper is to apply a novel decoupling control method, direct feedback linear (DFL),to VAV air-conditioning system, which is differences from local linear decoupling control method. Amodel of VAV air-condition room is developed by a typical air conditioning system. Using DFL control,decoupling control is realized among multi-control loops in VAV air conditioning system and a linearmulti-inputmulti-output model is obtained. According to the VAV air conditioning model the real-timeDFL control system is designed and simulated based on MATLAB/SIMLINK.

Audit thermique instrumenté des installations de climatisation Thermal monitored audit of air-conditioning systems

In hot summer days, in Bucharest the air temperature is over 36°C and the relative humidity exceeds 50 %. That explains the big air-conditioning demand for tertiary buildings. This paper deals with an experimental and a numerical investigation of an air-c

A case study on the application of underfloor air conditioning and ventilation system in a school assembly hall

Floor return (FR) type underfloor ventilation system was installed in the assembly hall of aprimary school in Hong Kong. Experimental investigations on the airflow and temperaturecharacteristics were conducted. Pollutant distributions were also measured with different freshair supply rates. Results reveal that the use of low momentum floor supply panels reduced therisk of draught discomfort and created a more significant temperature stratifications comparedto those with fan boosted type floor air terminals. Ventilation of polluted air was localized upto the occupants breathing level.

Control of temperature for productivity

The focus of this paper is on cost effectiveness of remedial measures for existing buildings in order to reduce high summer time indoor temperatures. A typical Finnish office building was selected for the analysis. The cost items included in the analysis are: the capital cost of the remedial measure (increase of ventilation, mechanical cooling added in central air handling unit), cost of the used energy (heat and electricity), and the cost of deteriorated productivity due to high temperatures.