HVAC mini project for heat ventilation air conditioning for technical seminar or it can be use for mini project for presentation in college.

1. NARSIMHA REDDY ENGINEERING COLLEGE
Design of air conditioning ducts
Submitted in partial fulfillment of
requirements for the award of the degree of
BACHELOR OF TECHNOLOGY
MECHANICAL ENGINNEERING
Under the esteemed guide
SURESH.P
Assistant professor (M.TECH)
Department of Mechanical Engineering
Submitted by
MD ZEESHAN 13X01A0366
SANDEEP SINGH 13X01A0392
ZAFARYAB HAIDER 13X01A03C2
MD RIZWAN 13X01A0367

2. Abstract
Earlier the use of air-conditioning for
comfort purpose was considered a luxurious
but now-a-day, it has been a necessity in
extreme climatic conditions, such as
extreme cold and hot in western countries.
Window air conditioners are preferred for
office rooms while large centralized units
are installed for conditioning the
auditorium, hospitals etc.

3. Air conditioning ducts
The purpose of air conditioning
ductwork is to deliver air from
the fan to the diffusers which
distribute the air to the room.
Air Moves Through the
Ductwork in Response to a
Pressure Difference Created by
the Fan

4. WORKING PRINCIPLES OF
DUCTS

5. Ductwork Considerations
Shape
Size
Aspect ratio
Velocity
Static Pressure

6. Materials
Sheet metal (by
gauge)
 Galvanized
 Iron
 Aluminum
Flexible
 Insulated
 Tube (socks)
01
01
01
02
02
03
04
04
05
05
05
06

7. Shape and Size
Round
Oval
Rectangular

8. Rectangular
Lower aspect ratios
 More energy efficient
 Use less ductwork
Velocity and Area have
an inverse relationship
to the CFM (CFM = V x
A)
Velocity and Pressure
Drop have a direct
relationship
W
D
Aspect ratio = W / D
1 to 1

9. Air Distribution Systems
Three Types
 Above Ceiling
 Displacement
 Under floor
Services
 Supply air
 Return air
 Ventilation air
 Relief air
 Exhaust air

10. Above Ceiling
Distribution System
horizontalhorizontal
heat pumpheat pump
supplysupply
ductduct
returnreturn
ductduct
diffuserdiffuser
return airreturn air
grillegrille

11. Other Design
Considerations
Thermal mass
Natural light
Solar shading
Control strategies
Life safety issues
Infiltration
Mixed Air
conditions
Energy in the air
Comfort level of
the air
The amount of
water in the air

12. DISPLACEMENT
PRINCIPLES
•Conditioned air moves upward past the
persons breathing zone.
•This invisible plume continues an upward
movement toward the ceiling.
•A person will breathe lower contaminant
levels vs. a mixing design.

13. Displacement
Advantages/Disadvantages
Advantages
 Moderate supply
air temperature
 Low velocity
 Air delivered to
the comfort zone
without mixing
 Accommodate
more outside air
for same energy
cost
 Very quiet
Disadvantages
 Higher initial
cost
 Less well
understood
 Too quiet

14. CONCLUSION
1)The cooling load calculation of an auditorium is done,
applying CLTD method and duct design is carried out by
equal friction method.
2)The calculated value of frictional pressure drop
is less as compared to existing plant or value used in
industry. Due to less value, duct diameter is increased
but loss in static pressure, velocity pressure can be
avoided. Smaller diameter of duct would increase noise
level. So requirement of sound attenuating devices may
need. Also probability of dampers is decreased with
increasing diameter. But first cost is increased with
increasing duct diameter
2) Due to proper branching of ducts, loss is
minimized in this design. But in existing plant, there is
straight branching in so many locations, which may