الفهرس 
Literature ReviewOnly 14 pages are availabe for public view
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Abstract
As there is a risk of CO contamination by vehicles running inside the car park.
All the global codes give great attention to ventilation in car-parked areas
(ASHRAE, NFPA, OSHA, The Egyptian Code for Ventilation). This research
was initiated with the objective of assessing jet fans impulsive ventilation “IV”
performance in such garages, where a 1350 m2 UG (2.65 m high) was
considered as a case study and studying its effect on CO contamination in car
park.
The involved parameters were investigated numerically; 39 scenarios were
proposed; visualized in a matrix and simulated by a Computational Fluid
Dynamics “CFD” model (i.e. ANSYS FLUENT 2019 R3). Natural ventilation
and impulsive ventilation were studied.
The proposed scenarios considered the jet fans “JFs” arrangement, in terms of
number and interspacing and location within the garage. Moreover, the
visualized matrix considered the JFs’ flow and realistic vehicle emission rates,
as they play a crucial role in the ventilation performance. ANSYS FLUENT
was operated and visualized airflow patterns so as contaminants distribution
within the garage.
Simulation results were obtained; analyzed and presented on graphs, where
they inter-related the involved parameters (i.e. air velocity distribution, air
change rate, and CO concentration levels) to assess the proposed scenario
performance.
The results highlighted valuable insights into the most suitable arrangement of
jet fans in UG. It flagged out the importance of adjusting the number of fans,
spacing, and location to attain a reasonable ventilation performance.
The research suggested implementing an inverter Variable speed drive system
in the ventilation system to provide 6 or 10 ACH and adjusting them based on
UG occupancy whether at normal load or peak load, Additionally, the On-Off
system allows for the utilization of different arrangements according to the load
requirements. A Collective Correlation was attempted to identify the values of
CO in PPM according to loads percentage and ACH for arrangement 3.