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Objectives

Discus final project

Load calculation

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Final ProjectGroup 1:

Heather Smith

Tommy Beales

Matt Leos

Group 2:

Patrick Gorman

Kenny Greaves

Matt McCarthy

Group 3:

Sarah JohnsonJocelyn Citty

Tobias Nilsson

Group 4:

Zaid Arzate

Brian BurchamJustin Barrett

Group 5:

Nick Williams

Stephen Mathai

Kevin Carbonnier

Group 6:

Marcus Allen

Josh Atkins

Matt Larson

Group 7:

StephenF

ridleyShahrukh Gaziani

Margaret Lawson

Group 8:

Marwa Zaatari

Megan Gunther

Elena Nirlo

Group 9:Gregory Arcangeli

Andrew Hoisington

Adam Keeling

Individual projects

Neil Woodson

Wesley Cole

Sami Kolahdoozan

Gautam Salhotra

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Project topics

1) VAV system design

Fresh air requirements and recirculation rate calculation

Selection of zonal and central HVAC components based on cooling and heating load components

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

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

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

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Project topics

3) Cooling systems and distribution

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)

- 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)

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DOAS with multi-split systems

Fresh air?

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DOAS fresh air configurations

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DOAS fresh air configurations

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Cooling and Heating Loads

(F

or Project)

Zone orientation

Commercial building

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Cooling and Heating Loads

(F

or 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 offresh air is in all spaces (except plenums)that produce 0.2 ACH.

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Cooling Load Calculation

Mostly computer based

Handouts for manual calculation http://www.ce.utexas.edu/prof/Novoselac/classes/ARE346N/Handouts/heatloss_table_2008.doc

http://www.ce.utexas.edu/prof/Novoselac/classes/ARE346N/Handouts/ASHRAE_%20Gains_Calculation_Tables.doc

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Heat Recovery Sensible and

Enthalpy wheel

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EconomizerEconomizer (fresh air volume flow rate control)

mixing

damper

fresh air

T & RH sensors

recirc. air

Controlled device is damper

- Damper for the air

- Valve for the liquids

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Economizer cooling regime

How to control the fresh air volume flow rate?

% fresh air

Minimum for ventilation

100%

If TOA < Tset-point Supply more fresh air than the minimum required

The question is how much?

Open the damper for the fresh air

and compare the Troom with the Tset-point .Open till you get the Troom = Tset-pointIf you have 100% fresh air and your still need cooling use cooling coil.

What are the priorities: - Control the dampers and then the cooling coils or - Control the valves ofcooling coil and then the dampers ?

Defend by SEQUENCE OF OERATION the set of operation which HVAC designer provides to the automatic control engineer

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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 < Tset-point start closing the damper till you get T indoor air = T set-pointOther variations are possible

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Desiccant wheel

Figure 3 A desiccant-based cooling system combined with regenerative heat exchanger, vapor compression cooling, andevaporative humidifier (hybrid system).