Transcript 389H_NO_24_Load_Calc_Project

Objectives
• Discus final project
• Load calculation
Final Project
Group 1:
Heather Smith
Tommy Beales
Matt Leos
Group 5:
Nick Williams
Stephen Mathai
Kevin Carbonnier
Group 2:
Patrick Gorman
Kenny Greaves
Matt McCarthy
Group 6:
Marcus Allen
Josh Atkins
Matt Larson
Group 8:
Marwa Zaatari
Megan Gunther
Elena Nirlo
Individual projects
Neil Woodson
Wesley Cole
Group 9:
Gregory Arcangeli
Andrew Hoisington
Adam Keeling
Sami Kolahdoozan
Gautam Salhotra
Group 3:
Sarah Johnson
Jocelyn Citty
Tobias Nilsson
Group 4:
Zaid Arzate
Brian Burcham
Justin Barrett
Group 7:
Stephen Fridley
Shahrukh Gaziani
Margaret Lawson
Project topics
1) VAV system design
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Fresh air requirements and recirculation rate calculation
Selection of zonal and central HVAC components based on cooling and heating load components
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For zones: VAV boxes, reheaters, reheater plumbing
For whole system: AHU and components, chiller & cooling tower, boiler, and electric power requirement
Control description – sequence of operation
Heat recovery system and or economizers
2) DOAS system design
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Fresh air requirement and split between air and hydronic loads (sensible and latent cooling loads)
Selection of zonal and central HVAC components based on cooling and heating load components
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For zones: fan coils and plumbing
For whole system: AHU and components, chiller & cooling tower, boiler, and electric power requirement
Control description – sequence of operation
Heat recovery system and or economizers
Project topics
3) Cooling systems and distribution
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Air cooled condenser vs. water cooled condenser (energy performance analysis)
Design of plumbing systems for campus and pumping stations
Control of centralized system
Saving with variable speed pumps
4) Duct Design (in Revit)
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- Diffuser selection, design of local and central duct system components
- Spacing issues and difference between round and square ducts
- Difference between manual calculation and calculation by Revit (for a section of the duct system)
- Balancing and fan selection
- Life cycle analysis and optimization (fan power consumption vs. system cost)
DOAS with multi-split systems
Fresh air?
DOAS fresh air configurations
DOAS fresh air configurations
Cooling and Heating Loads
(For Project)
Commercial building
»Zone orientation
Cooling and Heating Loads
(For Project)
»Cooling and heating load for each zone and whole building:
»Fresh air requirement based on number of occupants:
»To provide acceptable IAQ in the building, ventilation
» system supply minimal amount of
»fresh air is in all spaces (except plenums)
»that produce 0.2 ACH.
Cooling Load Calculation
• Mostly computer based
• Handouts for manual calculation
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http://www.ce.utexas.edu/prof/Novoselac/classes/ARE346N/Handouts/heatloss_table_2008.doc
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http://www.ce.utexas.edu/prof/Novoselac/classes/ARE346N/Handouts/ASHRAE_%20Gains_Calculation_Tables.doc
Heat Recovery Sensible and
Enthalpy wheel
Economizer
Economizer (fresh air volume flow rate control)
»Controlled device is damper
»damper
»fresh
» air
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»mixing
»recirc.
» air
»T & RH
sensors
- Damper for the air
- Valve for the liquids
Economizer – cooling regime
How to control the fresh air volume flow rate?
»If
TOA < Tset-point → Supply more fresh air than the minimum required
»The question is how much?
»% fresh air
»Open the damper for the fresh air
»and compare the Troom with the Tset-point .
»Open till you get the Troom = Tset-point
»If you have 100% fresh air and your
» still need cooling use cooling coil.
»100%
»Minimum for
» ventilation
»What are the priorities:
» - Control the dampers and then the cooling coils or
» - Control the valves of cooling coil and then the dampers ?
»Defend by SEQUENCE OF OERATION
» the set of operation which HVAC designer provides to the automatic control engineer
Economizer – cooling regime
»Example of SEQUENCE OF OERATIONS:
»If
TOA < Tset-point open the fresh air damper the maximum position
»Then, if
Tindoor air < Tset-point start closing the cooling coil valve
»If cooling coil valve is closed and T indoor air
» till you get T indoor air = T set-point
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»Other variations are possible
< Tset-point start closing the damper
Desiccant wheel
»Figure 3 – A desiccant-based cooling system combined with regenerative heat exchanger, vapor compression cooling, and
evaporative humidifier (hybrid system).