Erin FauldsArchitectural Engineering

Mechanical OptionSenior Thesis 2007

The Try Street Terminal Building620 Second Avenue

Pittsburgh, PA

Presentation OutlineBuilding IntroductionMechanical Analysis CFD ModelIAQ StudyConclusion

Try Street Terminal BuildingRenovation Project Art Institute of Pittsburgh (AIP)

Building HistoryExisting industrial warehouse Originally constructed in 1910230,000 SF with 20,500 SF building footprint9 stories above ground

Try Street Terminal BuildingRenovation ProjectArt Institute of Pittsburgh

Building IntroductionMechanical Analysis

CFD ModelIAQ StudyConclusion

Second Avenue

First Avenue

RenovationsReasons

AIP degree program changeRelocation of AIP campus

BenefitsMeet housing needs of AIPCloser to campusRestores older buildingBrings younger people back to city

Try Street Terminal BuildingRenovation ProjectArt Institute of Pittsburgh

Building IntroductionMechanical Analysis

CFD ModelIAQ StudyConclusion

Try Street Terminal BuildingRenovation ProjectArt Institute of Pittsburgh

Building SiteDowntown Pgh – between 1st & 2nd Ave.Surroundings/Neighbors

AIP campusPNC Bank Data CenterStation Square & SouthsidePublic transportationPublic Parking Authority’s

First Side Garage

Building IntroductionMechanical Analysis

CFD ModelIAQ StudyConclusion

Project TeamArchitect: TKA Architects

General Contractor: Massaro CorporationMechanical Engineer: McKamish

Electrical Engineer: Star Electric CompanyStructural Engineer: The Kachelle Group

Plumbing Engineer: Sauer, Inc.Fire Protection: Ruthrauff, Inc

Construction DatesOctober 2005 – June 2007

Try Street Terminal BuildingRenovation ProjectArt Institute of Pittsburgh

Building IntroductionMechanical Analysis

CFD ModelIAQ StudyConclusion

Features & FunctionsNew Architectural Features

Façade Restoration – Historic LandmarkMezzanine level between floors 1 & 22-story atriumLightwell in core of building (floors 2-9)

Building Functions650 Residents in 140 Apartments2,750 ft2 exercise room9,000 ft2 of retail space

Try Street Terminal BuildingRenovation ProjectArt Institute of Pittsburgh

Building IntroductionMechanical Analysis

CFD ModelIAQ StudyConclusion

Second Avenue

First Avenue

Existing Mechanical SystemConventional WSHP System

(1) 1 to 3 ton water source heat pump (WSHP) in each apartment

(1) 10 ton heat pump serves exercise room60-90F building loopCooling – (1) 370 ton closed circuit cooling towerHeating – (2) gas-fired boilers,

1340 MBH ea.

Try Street Terminal BuildingRenovation ProjectArt Institute of Pittsburgh

Building IntroductionMechanical Analysis

CFD ModelIAQ StudyConclusion

Conventional WSHP

Try Street Terminal BuildingRenovation ProjectArt Institute of Pittsburgh

Building IntroductionMechanical Analysis

CFD ModelIAQ StudyConclusion

Existing Mechanical System - Airside(4) Make-up Air Units (MAU)

100% OA rooftop unitsProvide ventilation for corridors

& apartments on floors 1-94,620 to 7,550 cfm per unit122 tons total cooling capacity2,285 MBH total heating

capacity

Try Street Terminal BuildingRenovation ProjectArt Institute of Pittsburgh

Building IntroductionMechanical Analysis

CFD ModelIAQ StudyConclusion

Existing Mechanical System - Airside(4) Air Handling Units (AHU)

Indoor self contained, air-cooled vertical package unitsSupply constant volume cooling of 47 tonsServe basement & 1st floor unassigned spaces3,000 to 6,000 cfm per unitElectric duct heaters provide 125 kW of heating

(1) 10 ton heat pumpSupplies 4,000 cfm OA to exercise room

Try Street Terminal BuildingRenovation ProjectArt Institute of Pittsburgh

Building IntroductionMechanical Analysis

CFD ModelIAQ StudyConclusion

Alternative Mechanical SystemsDesign Focus

Apartments on Floors 1-9Objectives

Implement geothermal systemReduce energy consumptionMaintain thermal comfortReduce maintenance

Try Street Terminal BuildingRenovation ProjectArt Institute of Pittsburgh

Building IntroductionMechanical Analysis

CFD ModelIAQ StudyConclusion

Geothermal Heat PumpsBenefits

Decrease energy consumptionLess O&M compared to conventional

DisadvantageInstallation cost

Types investigated: closed/open loopClosed: ground coupled heat pumps (GCHP)Open: ground water heat pumps (GWHP)

Try Street Terminal BuildingRenovation ProjectArt Institute of Pittsburgh

Building IntroductionMechanical Analysis

CFD ModelIAQ StudyConclusion

GCHP SystemHeat exchanged between water in pipes and ground soil Vertical System

Requires 250 to 300 ft2 per ton coolingHorizontal System

Requires 2,500 ft2 per ton coolingClosed loop system not selected

Site limitations

Try Street Terminal BuildingRenovation ProjectArt Institute of Pittsburgh

Building IntroductionMechanical Analysis

CFD ModelIAQ StudyConclusion

GWHP SystemOpen loop – water not confined to loop of pipesGroundwater – source of coolingPumping well – moves groundwaterPossible arrangements

Direct useStanding columnIndirect use

Try Street Terminal BuildingRenovation ProjectArt Institute of Pittsburgh

Building IntroductionMechanical Analysis

CFD ModelIAQ StudyConclusion

GWHP SystemDirect-use

Water used directly in heat pumpLimited to smallest applications

Standing ColumnWater used directlyWater produced & returned

to same wellProblems

Scaling of building equipmentSize of project

Try Street Terminal BuildingRenovation ProjectArt Institute of Pittsburgh

Building IntroductionMechanical Analysis

CFD ModelIAQ StudyConclusion

GWHP – Primary FocusIndirect-use

Utilizes plate heat exchangerIsolates building & ground loops

Two Well SystemProduction & Injection WellsNational Pollutant DischargeElimination System (NPDES)permit

PA – Class V, no additivesNPDES permit –not required!

Try Street Terminal BuildingRenovation ProjectArt Institute of Pittsburgh

Building IntroductionMechanical Analysis

CFD ModelIAQ StudyConclusion

Groundwater sourceUnderground River

Other names:Wisconsin Glacial Flow Aquifer

Constant 55FFresh, pure drinking source15 to 50 feet below surfaceAquifer construction

Like oval tunnel filled with rocks and gravelSides & bottom - solid rockTop - silt and clay

Water source for Point State Park Fountain

Try Street Terminal BuildingRenovation ProjectArt Institute of Pittsburgh

Building IntroductionMechanical Analysis

CFD ModelIAQ StudyConclusion

Heat Exchanger SizingOptimum Flow Rates

Building loop: 2 to 3 gpm/tonGroundwater loop: 1 to 2.25 gpm/ton

Heat of rejection = 4,200 MBH (controlling case)Heat of absorption = 1,053 MBHARI 325 rating for GWHP

Both EER & COP have 70F & 50F entering water temperature

Approach of 3-7FΔTgroundwater typ. less than 10F

Try Street Terminal BuildingRenovation ProjectArt Institute of Pittsburgh

Building IntroductionMechanical Analysis

CFD ModelIAQ StudyConclusion

Heat Exchanger SizingMueller 60MH model

286 plates1904 ft2 total area875 gpm – bldg loop788 gpm – gw loopApproach = 4.8FΔTgroundwater = 10.7F

Try Street Terminal BuildingRenovation ProjectArt Institute of Pittsburgh

Building IntroductionMechanical Analysis

CFD ModelIAQ StudyConclusion

Convention CenterApprox. 1 mile awayDrawdown test – 1100gpm available

Try Street Terminal BuildingRenovation ProjectArt Institute of Pittsburgh

Building IntroductionMechanical Analysis

CFD ModelIAQ StudyConclusion

Well DesignWell Spacing

Flow from injection to production well doesn’t need to be prevented

Inter-well flow needs to be sufficiently low

~ 4,400 ft2 available‘driveway’ & parkingRETScreen requires

~2,500 ft2

GWHP - Energy AnalysisHAP model

Direct-use30% reduction

in cooling cmpt. costIncreased pumping

costRETScreen model

Indirect-use Similar heating &

cooling loads to HAPReduced emissions

Try Street Terminal BuildingRenovation ProjectArt Institute of Pittsburgh

Building IntroductionMechanical Analysis

CFD ModelIAQ StudyConclusion

100.05.727809,263100.06.010849,282Grand Total

68.63.931555,50565.43.931555,505Non-HVAC Sub-Total

54.33.108439,18751.73.108439,187Electric Equipment

14.40.823116,31713.70.823116,317Lights

31.41.796253,75834.62.079293,777HVAC Sub-Total

0.00.00000.40.0233,201Cooling Tower Fans

9.30.53275,1286.70.40356,924Pumps

3.70.21430,2343.60.21430,214Heating

16.00.919129,84321.81.308184,884Cooling

2.30.13118,5542.20.13118,554Air System Fans

Percent of Total(%)

($/ft²)

Annual Cost($)

Percent of

Total(%)

($/ft²)

Annual Cost($)Component

Alternative WSHPExisting GWHPAnnual Compt. Costs

Cost ComparisonRETScreen

12 years-to-positive cash flowAIP – 20 year property

commitmentAlthough great initial cost,

would recommend system

Try Street Terminal BuildingRenovation ProjectArt Institute of Pittsburgh

Building IntroductionMechanical Analysis

CFD ModelIAQ StudyConclusion

Computational Fluids ModelProblem

Air & Temp. distribution inatrium spaces

Spaces evaluated2-story lobby (1,650 ft2)2-story exercise room (1,800 ft2) Total first floor area of 4,700 ft2

(4) 30 ft2 skylightsObjectives

Use Phoenics VR to generate 3-D modelAnalyze effectiveness of diffuser placement & supply air flow rate

Try Street Terminal BuildingRenovation ProjectArt Institute of Pittsburgh

Building IntroductionMechanical Analysis

CFD ModelIAQ StudyConclusion

Phoenics VRModel

Blockages – columns, floors, walls, etc.Inlet/Outlet – diffusers/doorwaysHeat source – flat plate evenly distributed over floor surface (5,000 & 12,000 W)

Results after 3,000 iterationsLeft convergence monitor

– not constantOkay for education purposes

Try Street Terminal BuildingRenovation ProjectArt Institute of Pittsburgh

Building IntroductionMechanical Analysis

CFD ModelIAQ StudyConclusion

Phoenics ModelVelocity Slices

Direction of air flowis correct

At occupant level -air flow <= 1 m/s

Try Street Terminal BuildingRenovation ProjectArt Institute of Pittsburgh

Building IntroductionMechanical Analysis

CFD ModelIAQ StudyConclusion

m/s

0.250.25-0.51

0.51-1.021.02-1.52

>1.52 problem

Air Velocity - ComfortOccupant Comfort

unnoticedpleasant

geneally aware of air movement

drafty

Try Street Terminal BuildingRenovation ProjectArt Institute of Pittsburgh

Phoenics ModelTemperature Slices

Diffuser stream – 59FAt occupant level - 66-70F

Building IntroductionMechanical Analysis

CFD ModelIAQ StudyConclusion

C

1517192123 73

TemperatureF

59636670

Diffuser placement & supply flow rates – acceptable!

Indoor Air Quality StudyObjective

Contaminant free apartments (select)Ultraviolet Germicidal Irradiation (UVGI) System

Complicated technologyUsed for air & surface disinfectionCommon types: in-duct, in-AHU, upper air distribution, standalone recirculation unitDestroy microbes: bacteria, mold, spores, germs

Try Street Terminal BuildingRenovation ProjectArt Institute of Pittsburgh

Building IntroductionMechanical Analysis

CFD ModelIAQ StudyConclusion

CREON2000 Room UnitPatented Technology

Focuses power of UV light on microbes Study – Journal of Asthma

Asthma symptoms – less frequent & severe

Low maintenance designReplacement of bulb & filter – once a year

Microbe ReductionHEPA - by 2-3 timesCREON2000 – by 20 times

Room Unit – offers flexibility in number of units installed

Try Street Terminal BuildingRenovation ProjectArt Institute of Pittsburgh

Building IntroductionMechanical Analysis

CFD ModelIAQ StudyConclusion

ConclusionGWHP indirect-use system

Reduces energy consumptionReduces emissionsMaintains thermal comfortLowers maintenance

Based on information available and calculations completed – Recommend!

Try Street Terminal BuildingRenovation ProjectArt Institute of Pittsburgh

Building IntroductionMechanical Analysis

CFD ModelIAQ Study

Conclusions

Try Street Terminal BuildingRenovation ProjectArt Institute of Pittsburgh

Building IntroductionMechanical Analysis

CFD ModelIAQ Study

Conclusions

Thank YouPenn State AE Mechanical Faculty – especially my

advisors: James Freihaut & Jelena SrebricClassmates – Malory & Patrick

Dave Lyon & Jim Synan at McKamishMy family & friends

Questions?