K10790 nileshprajapati rac me 6 th sem

Career Point Cares
Duct system in large Commercial Buildings
Major assignment
of
Refrigeration &Air conditioning
Submitted To:- Submitted By:-
Mr.Aditya Mishra Nilesh Prajapati
B.tech 6th Sem [Me]
Career Point Cares
Introduction:-
THE DUCT SYSTEM, used in air heating and air cooling your home, and large
commercial buildings is a collection of tubes that distributes the heated or
cooled air to the various rooms. This system can make a big difference in both
the cost and the effectiveness of heating and cooling the home. The duct
system can have an important effect on health of the occupants through the
distribution of indoor air pollution. Changes and repairs to a duct system
should always be performed by a qualified professional. This brochure is meant
to help you understand the problems that can affect the duct system and how
you can:
• Save money
• Improve comfort
• Protect health
Career Point Cares
General rules for duct design:-
1. Air should be conveyed as directly as possible to save space, power
and material
2. Sudden changes in directions should be avoided. When not possible
to avoid sudden changes, turning vanes should be used to reduce
pressure loss
3. Diverging sections should be gradual. Angle of divergence ≤ 20o
4. Aspect ratio should be as close to 1.0 as possible. Normally, it should
not exceed 4
5. Air velocities should be within permissible limits to reduce noise and
vibration
6. Duct material should be as smooth as possible to reduce frictional
losses
Career Point Cares
Lay Out
Career Point Cares
Career Point Cares
Objectives
1 to characterize energy losses in the duct systems. within
large commercial buildings, along with the pertinent physical
features of the ducts
2 develop and evaluate methods of measuring duct system
energy losses. Our broader program of research on large
commercial ducts includes modeling to quantify the
influence of these losses on HVAC system energy use 8 and
an investigation of the feasibility of sealing ducts in large
commercial buildings by injecting sticky aerosols into the
ducts.
Career Point Cares
Duct Design and Fan Performance
Commercial and residential and, industrial air duct system design must consider
1) Space air diffusion
2) Space availability
3) Noise level
4) Duct leakage
5) Duct heat gain and losses
6) Balancing
7) Fire and smoke control
8) Initial investment
9) System operating cost
Career Point Cares
DUCT MATERIALS
•Ductwork must meet local codes
•For years, galvanized sheet metal was used exclusively
Other ductwork materials
Aluminum
Fiber glass duct
Board Spiral metal duct
Flexible duct
Career Point Cares
Benefits of Properly Designed Installed Duct System
Adequate air flow
•Less conditioned air leakage
•Smaller, less expensive equipment
•Longer equipment service life
•Healthier, safer indoor air quality
•Reduced house air leakage
•Fewer call backs
•No Potential for Back drafting Appliances Higher energy efficiency
Greater comfort for occupants
Career Point Cares
AIR-MEASURING INSTRUMENTS FOR DUCT SYSTEMS
Velometer – Measures actual air velocity (how fast the
air is actually moving in the duct)
Air volume in cfm can be calculated by multiplying the
air velocity by the cross-sectional area of the duct in
square feet
Pitot tube – Used with special manometers for
checking duct pressure
Career Point Cares
DUCT INSULATION
A 15°F temperature difference from the inside of
the duct to the outside of the duct is considered
the maximum difference allowed before insulation
is necessary
Metal duct can be insulated on the outside and on
the inside
The insulation is joined by lapping it, stapling it,
and taping it
Career Point Cares
SUMMARY
Duct systems can be made of galvanized metal, aluminum,
fiberglass duct board, spiral metal, flexible duct or a
combination of different materials
Branch ducts deliver the proper amount of air to remote
locations in the structures
Balancing dampers are used to help ensure proper airflow
to the remote locations
The return air system can be configured as a central or
individual return air system
Career Point Cares
Friction in the duct slows the air flowing in it
Slower air experiences less friction
Air balancing ensures the proper amount of air
is delivered to each supply register
CFM = velocity x cross sectional area
The friction chart is used to properly size duct
systems
Career Point Cares
THANK YOU
1 sur 14

Contenu connexe

Tendances(20)

Energy efficient ventilation systemEnergy efficient ventilation system
Energy efficient ventilation system
lucaschinsheng1.8K vues
AC basic trainingAC basic training
AC basic training
Olapade Samuel B.Tech(Hon), PMP, BDP, AIPMA837 vues
Ventilation System Ventilation System
Ventilation System
DanishPathan7969 vues
Mini Split Air ConditionersMini Split Air Conditioners
Mini Split Air Conditioners
PexSupply1.9K vues
Aircondition energy saverAircondition energy saver
Aircondition energy saver
prabhus_19855 vues
Building air con. systemBuilding air con. system
Building air con. system
utsavkhatri1447 vues
Mechanical systemsMechanical systems
Mechanical systems
Sunil Surya1.4K vues
HVAC Case StudyHVAC Case Study
HVAC Case Study
Nate Lee1.3K vues
Hvac Hvac
Hvac
Vijay Kumar1.9K vues
HVAC operation and Maintenance HVAC operation and Maintenance
HVAC operation and Maintenance
AC Repair Local10.3K vues
Residential hvac systemResidential hvac system
Residential hvac system
Joy Clark734 vues
Air Conditioning case studyAir Conditioning case study
Air Conditioning case study
Sona Rawat4.5K vues
Building Services 1 ReportBuilding Services 1 Report
Building Services 1 Report
Melvin Lim989 vues
Hvac preventive maintenance scheduleHvac preventive maintenance schedule
Hvac preventive maintenance schedule
MUSTAFA AHMED ABDULJABBAR2.2K vues
Airconditioning system (ppt)Airconditioning system (ppt)
Airconditioning system (ppt)
Yuri Melliza935 vues
Air cooling systemAir cooling system
Air cooling system
Enviro Tech Industrial Products 603 vues

En vedette(8)

How to Travel in GermanyHow to Travel in Germany
How to Travel in Germany
Ron Heinz442 vues
Save Trams in KolkataSave Trams in Kolkata
Save Trams in Kolkata
Gaurab Banerji1.5K vues
Vikash opc pptVikash opc ppt
Vikash opc ppt
harshprajapati12202 vues
CV .  Qasim 1   2016 CV .  Qasim 1   2016
CV . Qasim 1 2016
QASIM ALZOABI271 vues
CV/ Resume QasimCV/ Resume Qasim
CV/ Resume Qasim
QASIM ALZOABI347 vues

Similaire à K10790 nileshprajapati rac me 6 th sem

Bs 2 group assignmentBs 2 group assignment
Bs 2 group assignmentShze Hwa Lee
967 vues88 diapositives
Buildingservices2 bld60503Buildingservices2 bld60503
Buildingservices2 bld60503Kailyn Lee
1.6K vues88 diapositives
Chapter4.pdfChapter4.pdf
Chapter4.pdfkarunagrawal2
130 vues41 diapositives

Similaire à K10790 nileshprajapati rac me 6 th sem (20)

HVAC Complete final.pptxHVAC Complete final.pptx
HVAC Complete final.pptx
Dayasagar Govidaraju26 vues
All Energy Exhibition & Conference, Glasgow, May 2017All Energy Exhibition & Conference, Glasgow, May 2017
All Energy Exhibition & Conference, Glasgow, May 2017
Hugo Gallagher (hugo@logis-tech.co.uk)207 vues
Air distribution ProductAir distribution Product
Air distribution Product
Ashutosh kumar Dubey8.1K vues
Bs 2 group assignmentBs 2 group assignment
Bs 2 group assignment
Shze Hwa Lee967 vues
Buildingservices2 bld60503Buildingservices2 bld60503
Buildingservices2 bld60503
Kailyn Lee1.6K vues
Chapter4.pdfChapter4.pdf
Chapter4.pdf
karunagrawal2130 vues
Buildings Service reportBuildings Service report
Buildings Service report
Jian Jia1.5K vues
Hvac complete finalHvac complete final
Hvac complete final
DayasagarGovidaraju11K vues
Chapter 8 duct design and sealingChapter 8 duct design and sealing
Chapter 8 duct design and sealing
sahiloct119692.3K vues
Air Distribution SystemsAir Distribution Systems
Air Distribution Systems
Addisu Dagne Zegeye978 vues
Underground car parking ventilation systemUnderground car parking ventilation system
Underground car parking ventilation system
Mohamed Hashish17.3K vues
Building services.pptxBuilding services.pptx
Building services.pptx
priyanka41551423 vues
Point 2.pptxPoint 2.pptx
Point 2.pptx
PoojaPatil4891943 vues
Air conditioning system Air conditioning system
Air conditioning system
Educational Learner1.4K vues
Comparison between SystemsComparison between Systems
Comparison between Systems
Victor Ashkenazy638 vues
Air conditioning system Air conditioning system
Air conditioning system
Deepak Kindo8.6K vues

K10790 nileshprajapati rac me 6 th sem

  • 1. Career Point Cares Duct system in large Commercial Buildings Major assignment of Refrigeration &Air conditioning Submitted To:- Submitted By:- Mr.Aditya Mishra Nilesh Prajapati B.tech 6th Sem [Me]
  • 2. Career Point Cares Introduction:- THE DUCT SYSTEM, used in air heating and air cooling your home, and large commercial buildings is a collection of tubes that distributes the heated or cooled air to the various rooms. This system can make a big difference in both the cost and the effectiveness of heating and cooling the home. The duct system can have an important effect on health of the occupants through the distribution of indoor air pollution. Changes and repairs to a duct system should always be performed by a qualified professional. This brochure is meant to help you understand the problems that can affect the duct system and how you can: • Save money • Improve comfort • Protect health
  • 3. Career Point Cares General rules for duct design:- 1. Air should be conveyed as directly as possible to save space, power and material 2. Sudden changes in directions should be avoided. When not possible to avoid sudden changes, turning vanes should be used to reduce pressure loss 3. Diverging sections should be gradual. Angle of divergence ≤ 20o 4. Aspect ratio should be as close to 1.0 as possible. Normally, it should not exceed 4 5. Air velocities should be within permissible limits to reduce noise and vibration 6. Duct material should be as smooth as possible to reduce frictional losses
  • 6. Career Point Cares Objectives 1 to characterize energy losses in the duct systems. within large commercial buildings, along with the pertinent physical features of the ducts 2 develop and evaluate methods of measuring duct system energy losses. Our broader program of research on large commercial ducts includes modeling to quantify the influence of these losses on HVAC system energy use 8 and an investigation of the feasibility of sealing ducts in large commercial buildings by injecting sticky aerosols into the ducts.
  • 7. Career Point Cares Duct Design and Fan Performance Commercial and residential and, industrial air duct system design must consider 1) Space air diffusion 2) Space availability 3) Noise level 4) Duct leakage 5) Duct heat gain and losses 6) Balancing 7) Fire and smoke control 8) Initial investment 9) System operating cost
  • 8. Career Point Cares DUCT MATERIALS •Ductwork must meet local codes •For years, galvanized sheet metal was used exclusively Other ductwork materials Aluminum Fiber glass duct Board Spiral metal duct Flexible duct
  • 9. Career Point Cares Benefits of Properly Designed Installed Duct System Adequate air flow •Less conditioned air leakage •Smaller, less expensive equipment •Longer equipment service life •Healthier, safer indoor air quality •Reduced house air leakage •Fewer call backs •No Potential for Back drafting Appliances Higher energy efficiency Greater comfort for occupants
  • 10. Career Point Cares AIR-MEASURING INSTRUMENTS FOR DUCT SYSTEMS Velometer – Measures actual air velocity (how fast the air is actually moving in the duct) Air volume in cfm can be calculated by multiplying the air velocity by the cross-sectional area of the duct in square feet Pitot tube – Used with special manometers for checking duct pressure
  • 11. Career Point Cares DUCT INSULATION A 15°F temperature difference from the inside of the duct to the outside of the duct is considered the maximum difference allowed before insulation is necessary Metal duct can be insulated on the outside and on the inside The insulation is joined by lapping it, stapling it, and taping it
  • 12. Career Point Cares SUMMARY Duct systems can be made of galvanized metal, aluminum, fiberglass duct board, spiral metal, flexible duct or a combination of different materials Branch ducts deliver the proper amount of air to remote locations in the structures Balancing dampers are used to help ensure proper airflow to the remote locations The return air system can be configured as a central or individual return air system
  • 13. Career Point Cares Friction in the duct slows the air flowing in it Slower air experiences less friction Air balancing ensures the proper amount of air is delivered to each supply register CFM = velocity x cross sectional area The friction chart is used to properly size duct systems