This slides will explain more about pressure factors in fabric duct system by DuctSox - represented in Indonesia by Tawada CleanTech. For further information contact Tawada CleanTech at 021 5794 1139 or marketing@tawadacleantech.com

2.  Friction loss on fabric duct system by DuctSox
 Effects on velocity pressure, static regain and
static pressure
 Effects on the uniformity of the outlet air

3.  Research done at the Mechanical Engineering
department of Tennessee Tech University (TTU)
 Same research lab trusted by ASHRAE to create
ASHRAE’s Duct Fitting Database

4.  DuctSox comparing two fabric duct systems:
› Fabric duct with an internal frame
› Fabric duct without an internal frame
 Results:
› Pressure loss difference between two types of systems is
very small

6.  Static pressure is provided by the HVAC unit
(AHU)
 Inflation and operation of a fabric duct system is
dependent on static pressure (SP), NOT inlet
velocity

8.  Velocity pressure (VP) is kinetic energy and
slowly changes forms to a useful potential
energy or static pressure regain (SPR) as the air
travels down the constant diameter duct

9.  For most systems, the pressure will be higher at
the endcap than at the inlet due to SPR

10.  In fabric duct system, SPR is common occurrence
due to constant diameter sizing
 Internal damper (or AFD) is used to adjust SP and
reduce the pressure difference
 AFD creates more uniform air dispersion through
the whole length of duct

11. Rukan Permata Senayan A 20-21
Jl. Tentara Pelajar no. 5
Jakarta 12210 INDONESIA
Ph. 021 5794 1139
e. marketing@tawadacleantech.com
w. www.tawadacleantech.com