PREDICTING OF REFRIGERANT LEAKAGE IN A CONDITIONED ROOM: A NUMERICAL STUDY LEAKS DISTRIBUTION R-32 REFRIGERANT IN A/C SPLIT UNIT
DOI:
https://doi.org/10.11113/aej.v12.16499Keywords:
CFD, Difluoromethane, Distribution, ANSYS Fluent, A/C split, Hydrocarbon Refrigerant, CFD ANSYS Fluent, Difluoromethane, Distribution, AC Split, LeakageAbstract
Hydrocarbon Refrigerant R-32 called difluoromethane is one alternative solution used for Air Conditioning (A/C) unit split, but the weakness is flame property. This study investigates and analyzes flammable refrigerant difluoromethane distributions in the room affected by the A/C unit's leakage. It discusses the distribution of flammable refrigerant R-32 (difluoromethane) in an air-conditioned room. The simulation uses three variations of mass flow rate (leakage) and three airflow rate variations: low, medium, and high cold airflow velocity. Numerical calculations are used in CFD ANSYS FLUENT software with a model developed by Species Transport, SIMPLE algorithm, solver using pressure-based, mesh type is the dominant quadrilateral (rectangle). Turbulent modeling uses K-Epsilon standards. CFD analysis in the transient system condition results from numerical simulation, indicating that the leak will run out after 180 seconds with 0.005 kg/s (0.5 m/s). The moderate leak rate of 0.002 kg/s for R-32 is 450 seconds (7.5 minutes). The slower 0.001 kg/s with 0.1 m/s airflows for the R-32 ends after 900 seconds (15 minutes). The air and flow mass flow can affect the distribution and directly difluoromethane to the conditioned room. The effect of airflow rates and positioning holes in the concentration leaks is also analyzed when the unit's refrigerant leak is indoors as the air conditioner works.
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