Paper 4
Analysis of the Ventilation System
of an Isolation Room for a Hospital
Rajeev
Kumar, Ravi Kumar and Akhilesh Gupta
Department
of Mechanical & Industrial Engineering, Indian Institute of
Technology, Roorkee,
Roorkee –
247667, India
Abstract
The present work contains
the details of an investigation of air diffusion and comfort issues of an
isolation room of a hospital. Two types of cases have been chosen for a
unidirectional ventilation system of the isolation room i.e. for immuno-suppressed
patients and infectious patients. The patient’s body is simulated as a
cylinder with approximate values for the physical and thermal properties
of a human body and is treated as a constant heat source. The height of
the inlet vent was varied and mean residence time and draught rating (DR)
were studied. The work also involved investigation into the motion and
average residence time of a contaminant that could possibly accompany the
supply air and the bacteria that can be released from an infectious
patient’s mouth by means of breathing, coughing or sneezing. The results
reveal that the height of the inlet vent significantly affects the
velocity and draught distributions and the residence times of bacteria and
contaminant.
Key words: Air
distribution, ventilation, isolation room, draught rating, bacterial
contamination.
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