Case Study: CFD analysis for the industrial ventilation in which Air distribution is done by the fabric ducts

1. Industrial Ventilation
For a ventilation system in any industrial
environment, meeting process requirement
efficiently along with human comfort is a rare
possibility; often they are over designed to
compensate for any hidden issue in the design
itself. These systems does the work but at a higher
cost as they are not optimized for efficient
performance and energy saving. In general
industrial environment contaminant control,
human comfort and energy efficiency are main
requirement of HVAC system. For pharmaceutical
and food industry meeting the process requirement
of specific temperature and humidity with human
comfort is difficult to achieve and mostly results in
over-sized HVAC equipment and inefficient system.
CFD analysis helps to evaluate the air distribution
inside the concerned space and achieve process
requirement efficiently with human comfort and
contaminant control.
HVAC Setup and Duct Layout in Industrial Shed

2. Case study: CFD analysis for
the industrial ventilation in
which Air distribution is done
by the fabric ducts
The goal of analysis was to analyse air system
for a factory shed in order to provide
comfortable environment for workers inside and
also achieve the necessary requirements of
process in specific areas in terms of
temperature and humidity. The CFD analysis and
project results provide an overview of this
project.
Proper air distribution is to be maintained with
the installed system. The following criteria were
to be met by the newly designed system:
- The temperature of around 23.9 0C is to be
maintained at all times.
- Relative humidity of about 55% is to be
maintained in the area.
- Meeting a Process specific requirement of
temperature and humidity Air Supply Details for Ducts

3. The 3D model for simulation was prepared as per the architectural drawings and
layout received. Heat loads from equipment, occupants, solar load were assigned. Air
conditioning systems was modelled as per the HVAC drawings.
Velocity profile at Human Height 3D Air Streams from duct

4. Velocity profile in section Plane Temp profile at Human Height

5. Temp profile near equipment RH profile at Human Height

6. Based on the results of the steady state CFD simulation, we were able to conclude as
follows:
The average velocities obtained at the height of 1.5m is 0.53 m/sec, which shows that there is
proper air distribution inside the factory.
 Temperature range obtained at the height of 1.5m in the occupants area is 22.0-29.00 degC &
near to the equipment machinery it was 34 degC. These higher temperatures obtained near the
machinery are mainly due to higher heat loads from the equipment and able to meet the process
requirement.
 Relative humidity obtained at the height of 1.5m ranges from 38% to 57% at hot spots near the
machinery & 38% to 53% around the machinery. Which shows that near & around the machinery
the relative humidity was close to design relative humidity of 55 %.
 Pressure Losses obtained in the duct near the AHU Supply are as Section-1 (15000 CFM) = 197 Pa,
Section-2 (25000 CFM) = 195 Pa, which is close to the static pressure available from the AHUs.
Based upon the above data the system was assured with to meet the process requirement as well
as the human comfort criteria with the minimum airflow and static pressure requirement.

7. Case Study
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