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New York Flushing Meadows Indoor Pool/Ice Rink A Huge Engineering Challenge
The most striking feature of the new $60 million Flushing Meadows Corona Park
Pool & Ice Rink is its 20-foot-high wall of windows that affords a panoramic
view of the surrounding New York City urban oasis of natural beauty, but it wouldn’t
be possible without the project engineer’s HVAC design.
Flack & Kurtz, New York, designed separate state-of-the-art HVAC systems
that not only keep the Olympic sized pool and natatorium’s 170-foot-long
wall of windows clear of condensation and the ice rink free of fog regardless
of outdoor temperatures, but also include an energy-saving green strategy utilizing
heat recovery.
The 1,255-acre site is home to tennis’ U.S. Open and baseball’s Shea
Stadium, but was once a city dump where trash was burned and shoveled onto 100-foot-high
hills during the early 20th Century. After two World’s Fairs and a short
term as the United Nations headquarters, the Queens-based park has been returned
to its original natural beauty and is now New York’s largest. The newest
addition, the 110,000-square-foot pool and rink facility might someday host
competitive events if and when New York becomes an Olympic site.
Keeping the facility free of condensation was the responsibility of a mechanical
design team led by Flack & Kurtz’ Gary Pomerantz, P.E., executive
vice president, and Cathy Chang P.E., HVAC design engineer. Overseeing the
project
was Gregg Stanzione, senior project manager at general contractor, Bovis Lend
Lease, New York.
The key to keeping the pool dehumidification at 50 to 52 percent relative
humidity (RH) are two RS-562 Dry-O-Tron® heat recovery dehumidifiers by
indoor air quality equipment manufacturer, Dectron Inc., Roswell, GA., both
of which have
a moisture removal capacity of 390-lbs/hr. Although 90-percent of the roof
is supported by cable, the design team appropriated a conventionally supported
flat
rooftop to support the huge 45-foot-long, 10-foot-high units.
The rigging and placement of the huge units was the most challenging part
of the project for mechanical contractor, Trystate Mechanical, Inc., Yonkers,
NY, according to senior project manager, Joseph Romano.
Aside from dehumidification, the units also heat and cool the space to 86º
F and help bolster the building’s sustainability strategy with heat recovery
to provide free 84º F pool water heating the majority of operation. An integral
Raypak, Oxnard, CA, boiler, which provides on-demand supplementary pool heating,
was factory-integrated along with condensers into each package dehumidifier for
single source responsibility. The unit was physically tested under simulated
operating conditions of Corona Park in Dectron’s state-of-the-art factory
testing laboratory.
“
It makes a lot of sense - as far as installation costs and product reliability
- to have so many different functions (pool water heating, space cooling, dehumidification,
etc.) integrated into one unit by one manufacturer and tested before it arrives
on site,” said Chang, who worked with manufacturer’s representative,
SRS Enterprises, Brooklyn, NY on customizing the dehumidification units.
Adds Pomerantz: “We considered using the project’s two 1 million-Mbh
domestic water (Smith Cast Iron Boilers, Westfield, MA) boilers to add supplemental
pool water heating through a heat exchanger, but running supply and return
pool circulation piping to the roof would have raised the HVAC installation
costs
considerably.”
Another energy-saving feature Flack & Kurtz specified was the Smart Saver
factory-installed at Dectron, which uses warm exhaust air to preheat incoming
outdoor air. Outside air is efficiently controlled and gauged by the number
of occupants, time of day, and/or by CO2 sensors when a capacity of 500 spectators
attend events.
Besides dehumidification, the Flack & Kurtz team also worked with the project
architects HOM & Goldman, New York and Handel Architects, New York, to
specify extra condensation safeguarding with triple-glazed windows by Kawneer,
Norcross,
GA, and thermally-broken mullions.
Airflow in a highly evaporative space such as a natatorium is critical. Flack & Kurtz
value engineered the air distribution system with the specification of DuctSox,
Dubuque, IA, fabric ductwork, which saved the project approximately 75 percent
in installation labor and material costs versus conventional metal duct. The
air distribution design is perimeter dual parallel duct with Comfort-Flow, which
distributes 85 percent of the air through a linear diffuser running the entire
duct length and 15 percent through the fabric to prevent condensation from forming.
The outer loop washes the walls and windows with its linear diffuser, while the
inner run washes the ceiling. Eliminating hot spots is Flack & Kurtz’s
return air strategy which places four grills high above the spectator section
and a linear grill midway on the same wall.
Additionally, the specified Sedona-SM model has a built-in anti-microbial
fabric treatment that prevents mold/mildew from harboring in the ductwork’s
fibers. This will improve IAQ as well as eliminate the need for periodical
painting with
toxic coatings that are required with metal duct to prevent premature corrosion
in humid environments.
Since the overhead ductwork broadcasts warm dry air on the upper half of
the windows, additional heating for the bottom portion is provided by hydronic
baseboard heating from Sterling Hydronics, Westfield, MA. Under deck air distribution
with
metal ducts was considered, however, hydronic baseboard was considered a value-engineered
alternative that could heat the bottom half of the windows equally well. Additionally,
under deck duct diffusers are a notorious maintenance problem because they
collect dirt, water and debris, according to Pomerantz.
While the rink and pool are housed in the same complex, their HVAC systems
and particularly their mandatory vapor barriers are positioned significantly
differently. “The
key was to design the building envelope so that there were no weak points where
moisture or condensation could migrate,” said Pomerantz.
To eliminate moisture ex-filtration during winter, the 18,000-square-foot
natatorium’s
vapor barrier is positioned just inside the interior walls followed by insulation
and high R-factor foam-filled concrete panel exterior walls. Conversely, the
14,000-square-foot ice rink’s vapor barrier is positioned next to the
exterior concrete walls followed by insulation and the interior walls to prevent
moisture
infiltration during humid summers. Since the pool has a higher dew point than
the rink, the wall separating the two rooms has a pool vapor barrier positioning.
Besides vapor barrier placement, another concern was the two 180-foot-high
towers that penetrate through the top of the structure to anchor a series of
roof support
cables. Consequently, the poles became temperature transfers during extreme
outdoor temperature conditions that are vastly different than the interior
dew points.
Thus, Flack & Kurtz conceived an innovative system of Chromalox, Pittsburgh,
PA, electric contact heaters that would keep the towers even tempered and above
interior dew points to eliminate condensation.
Like the pool, the ice rink requires dehumidification to eliminate humidity
that commonly occurs not from evaporating water, but due to humidity generated
by
skaters’ respiration as well as that of a 400-spectator section capacity.
Thus, Flack & Kurtz specified a Dectron RK-120 Dry-O-Tron customized with
an enthalpy wheel option to keep a design set point of 60º F and 40 to 50-percent
RH. To eliminate fogging at ice level that’s common in rinks and keep condensation
from forming on the ceiling, two ceiling-hung DA-2 Dry-O-Tron dehumidification
units control fog. “We wanted to keep all the dehumidification equipment
on the site under one manufacturer and one methodology - mechanical versus desiccant
- which would make future maintenance and service easier,” added Chang.
Flack & Kurtz also did an energy study during the project design and
found mechanical dehumidification would save the facility significantly in
annual
operating costs versus desiccant, according to Pomerantz.
Other HVAC equipment on the project includes Greenheck, Scofield, WI, exhaust
fans and Carrier, Syracuse, NY, conventional DX equipment for air conditioning/heating
the complex’s small meeting rooms and offices.
If the Olympics come to New York in the future, the Corona Park facility
will be a showcase of engineering for the rest of the world to see.
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