CASE STUDY: NEW NCAA DIV. I COLLEGE BASKETBALL ARENA Stephen W. Duda, PE LEED AP Director, Mech Engineering Ross & Baruzzini, Inc. sduda@rossbar.com Acknowledgements: Ellerbe Becket, Architects, Kansas City, MO Flack + Kurtz, Engineers, New York, NY Kwan Chi, P.E., Member ASHRAE Jackson D. Waterbury III, P.E., Member ASHRAE St. Louis, MO Miami, FL Indianapolis, IN New York, NY Orlando, FL ASHRAE 2009 Annual Conference / Louisville, KY June 23, 2009 / Seminar #32 TC 9.01 Large Building Air-Conditioning Systems 1
BACKGROUND INFORMATION Opened Nov. 2008 Largest indoor hall in Southwestern MO Varsity athletics Shows & Concerts Rodeos & Similar Religious Revivals Entertainers from nearby Branson, MO State High School Championship Tournaments 2
OUTLINE Engineering Challenges related to Large Arenas... Load Profile Stratification Outdoor Air Smoke Control Luxury Suites Energy Efficiency Lessons Learned 3
LOAD PROFILE 11,000 capacity for Varsity Basketball and some shows. Normal day-to-day occupancy 100 +/-. Peak load is 1500 tons (5,275 kw) cooling capacity. How to design for both peak and farless-than-peak use? 4
LOAD PROFILE Separate Air-Handling Unit (AHU) systems for service areas, lockers, offices, etc. Use one bowl AHU (of four) for practice, intramural, and physical education activity. Chilled water is taken from campus chilled water network (presented at Seminar #8 of 2006 ASHRAE Winter Meeting in Chicago) for good part-load efficiency. Hydronic coil control valves are pressure-independent. Hybrid boiler plant of large & small hydronic boilers. 5
STRATIFICATION AVOIDANCE Cold air should be delivered high, but with long throw needed for air-change effectiveness. Warm air should be delivered low, but layout is impractical. If air outlets are selected for good throw at peak load, will they perform adequately at part load? 6
STRATIFICATION AVOIDANCE Main bowl ring duct concept was applied. Four (4) variable-volume AHUs feed the ring duct. Supply air outlets are arranged in groupings of three: Horizontal, Vertical Down, and 45º Downward. Each supply air outlet grouping includes a motorized damper. As load (and therefore, airflow) decreases, many supply air outlet groupings are shut off completely, allowing those that remain open to throw at ~full capacity. Mix of high and low return air inlets. 7
8
9
OUTDOOR AIR Complied with ASHRAE Standard 62.1-2004. 0.30 cfm/sf (1.5 L/s m 2 ) plus 7.5 cfm/occupant (3.8 L/s occ) Equates to approximately 9 cfm/occupant (4.5 L/s occ) Demand Controlled Ventilation (DCV) modulates outdoor air for 1100 ppm CO 2 and to maintain 0.05 in wc (12.5 Pa) positive building pressurization. CO 2 sensors (4) located in main return air ducts, one per quadrant. 10
SMOKE CONTROL Two Zones: Bowl & Concourse. Rejected five-zone concept as too complicated. Dedicated UL-Listed Smoke Exhaust Fans, but with common path through Return Air Ducts. Makeup air through four main bowl AHUs, plus direct louvers from the outdoors (insulated dampers). 11
12
13
LUXURY SUITES Four-pipe fan coil units (FCUs) in each Suite. Run only during Occupied Mode via use of a relay connected to automation system. Relays were initially wired backward, so FCUs ran all the time except when occupied. Commissioning! Suites are permanently open to the bowl, so outdoor air is not specifically delivered to Suites. 14
LUXURY SUITES 15
ENERGY EFFICIENCY FEATURES Variable Air Volume (VAV) throughout. Full air-side economizers throughout. Campus chilled water takes advantage of diversity. Occupancy control for Suites. Hybrid boiler plant -- large & small boilers. Boiler plant shared with adjacent former arena. Demand Controlled Ventilation (DCV). 16
LESSONS LEARNED Design Team was Told: No Ice Shows, No Pyrotechnics. Both were held within first five months. Additional exhaust is available for motor vehicles. Physically attached to former varsity basketball arena. Some simultaneous events. Building Leakage Like a Giant Barn. Partitions not well sealed beneath stair step risers. Poor seal of partitions at curtainwall. Maintenance of damper motors, other high items. Actuators mis-installed too far from catwalk. 17
THANK YOU Thank you for attending Seminar #32. Questions? 18