AIRPORT TERMINAL HVAC DESIGN
GUIDELINE
1. HEAT LOAD
Outdoor Condititons (Source - Hvac Specs 1 April 2015 ) Latitude 29.22 North
Longitude 47.98 E Altitude 55 M
Summer temperature: 48 °C db, 25.5 °C Wb
Winter temperature: Dry bulb: 4.5 °C Wet bulb: 2 °C Average daily temperature range: 13.33° C
Envelope Data (Source - CD-A0000-A-RPT-010-0) The minimum clearance below false ceiling in the main public spaces is 9m. The minimum clearance below false ceiling in the secondary public spaces is 4m. The minimum clearance below false ceiling in nonpublic spaces is 3.5 m
The minimum area of the clear openings in the landside facade is 2600 m² (excluding structure, mullions) The minimum area of the clear openings in the airside facade is 2800 m² (excluding structure, mullions) A minimum size of 4m² for at least 90% of the glazed curtain wall panels is required.
The visible width of the curtain wall mullions seen from the outside shall not exceed 80mm The Airside and Landside façade (Front entry and last check gates) are curtain walls.
The air intakes and exhausts shall be avoided The Side façade shall be covered with aluminum cladding.
The air intakes and exhausts shall be covered with louvers. The louvers design shall be consistent with the aluminum cladding covering the façade.
A minimum size of 2m² for at least 90% of the cladding panels is required
A minimum roof overhang (from the façade to the edge of the roof) of 2m is required above the side facades. A minimum roof overhang (from the façade to the edge of the roof) of 10m is required above the airside and landside facades.
A minimum roof overhang (from the façade to the edge of the roof) of 2m is required above the side facades.
The minimum area of the clear openings in the roof is 7500 m². For roof,
Extruded-Polystyrene Board Roof Insulation: ASTM C 578, of type VI, with maximum flame-spread and smoke-developed indexes of 75 and 450, respectively, per ASTM E 84.
1. Density 29 kg/cu m
2. Compressive Strength 276 kPa
3. Thermal Resistance: 50 mm thick 1.76 K.m2/W [10 F. ft2.h/Btu].
Thermal and Optical Performance Properties: Provide glass with performance properties specified based on Manufacturer's published test data, as indicated below:
1. Center-of-Glass U-Value for vertical glazing: ≤1.1 W/m².K.
2. Center-of-Glass U-Value for horizontal glazing (rooflights): ≤1.7 W/m².K. 3. Center-of-Glass Solar Heat Gain Coefficient: ≤ 25%.
4. Light Transmittance: ≤ 50%.
Louver Performance Ratings:
a. Free Area: Not less than 0.74 sq. m for 1,220-mm-wide by 1,220-mm-high louver. b. Air Performance: Not more than 25-Pa static pressure drop at 3.6-m/s free area velocity.
Description of the HVAC system:
During concept stage, it is very difficult to say the cooling load figures. Based on area, and activity, the tentative idea have been established. The calculation is required after architecture specify the shape and dimension etc. The cooling load will be within 2000 –2500 TR.
The following areas have to be looked into:
1) Provision of thermal energy storage according to Local code –
MEW. The
space requirement should be complied with architecture in design stage . It is advisable to discuss with MEW after plotting the cooling load profile related to requirement of thermal energy storage during peak load operation.2) Energy recovery unit related to reduction of fresh air load should
be considered according to MEW code.
Primary – secondary system can be adopted related to chilled water distribution. Natural draft cooling towers can be placed on roof of plant room. Suitable location of thermal storage should be considered either in basement and can be interfaced with Chilled water distribution system.
In office areas, under floor distribution system can be considered with floor mounted air conditioning modules and floor mounted air diffuser – active type, controlled by individual controller in master‐ slave principle.
In big areas like hall, AHU should be placed in a corner or roof and duct can run at high level either by Jet diffuser or suitable wall induction displacement diffusers. In special areas where glazing is obstructing to run duct in perimeter side wall, under‐floor duct with free standing recirculation air cooling unit can be considered. Suitable Energy Recovery unit related to energy saving according to ASHRAE 90.1 and MEW guideline code should be adopted and the placement may be considered on roof in co ordination with Architecture.
Computer Room Air‐Conditioning (CRAC) system shall be provided for accurate control of temperature and relative humidity within the IT/Sever facility rooms. Smoke ventilation system should be provided as per KFD regulations and NFPA standards. Stairs and lift wells should be pressurized mechanically by Fresh Air fans. Smoke ventilation should be provided through smoke extraction fans located at mechanical floors or on the roofs
Public Hall, Large volume area smoke evacuation will be provided by inducting fresh air at the ground floor level (with the assistance of automatic doors), and will be exhausted through smoke exhaust fans
Ait filter will be as per ASHRAE 52 or Eurovent 779 ‐2002 eqv. The MERV is the best measure.
Office area ‐ MERV – 9 (Pre‐ MERV 7, Bag – MERV ‐ 9) Prayer Hall – MERV 13. (Pre‐ 7, Bag – 13)
Smoking room ‐ MERV – 16 or better. ( pre‐ 7, bag ‐13, absolute‐ 16) . All fresh air fans shall be provided with washable 50 mm thick
3. MEW REQUIREMENTS
Kuwait airport is 10 km far from sea and a coastal region
6.1.1 Walls and
Roofs
Table 6.1 provides a list of the maximum allowable overall heat transfer coefficients (U) for variety of wall and roof constructions and their external color.
a) Exposed floor: Exposed floors in multistory apartment buildings or similar
constructions shall not have a U value of more than 0.568 W/(m2 .K) (0.1 Btu/(h.ft2 . °F)).
b) Columns and beam insulation: Columns and beams should be insulated in a manner similar to corresponding walls and roofs. Accordingly, their U values should not exceed 0.568 W/(m2 .K) (0.1 Btu/(h.ft2 .°F)) for the columns and 0.0398 W/ (m2.K) (0.07 Btu/(h.ft2. oF)) for the beam. In case the columns and beams are not insulated, this requirement shall be compensated for by additional insulation on walls/roofs.
c) Slab-On-Grade Insulation (for buildings without basements): It should be water resistant, laid horizontally on the slab at the inner side of external walls and extends a distance of 120 cm from the wall. The R value for the insulation material should not be less than R7 (1.4 m2 .K/W).
d) Below-Grade Wall Insulation: Below-Grade Wall shall have a rated R-value not less than the R-value of the Above-Grade Wall.
Note: The envelope components (Exterior Walls, Roofs and Floors) of unconditioned spaces connected to conditioned spaces shall have U-values similar to the
Water-cooled
chillers shall be used
for all projects in the
interior region of
Kuwait with total
operating plant capacity
of 500 RT and above, as
well as for all projects in
the coastal region
of Kuwait with total
operating plant capacity
of 1,000 RT and above
Projects
with partial
occupancy and cooling
load
capacity in
the range from 500 to 1000 RT in the coastal region shall use air cooled chillers. The system type (air or water cooled) shall be based on the diversified cooling load before applying partial cool storage. All buildings shall use a CRU (such as rotary-wheel, etc.) when:
1. The recoverable exhaust air quantity is equal to or more than 2,000 CFM (940 l/s) for all buildings in the coastal region,
2. The recoverable exhaust air quantity is equal to or more than 3,000 CFM (1410 l/s) for buildings in the interior region. The CRU shall have a minimum efficiency of 75% for all buildings in the coastal region as well as in buildings with high ventilation rates (buildings peaking at wet bulb prioritization) in the interior region. For toilets use heat pipe recovery ahu units
Thermal Storage
Cool storage (ice, water or eutectic) is encouraged and recommended for partially occupied buildings with plant production capacity of below 500 RT. However, for buildings with plant production capacity of 500 RT and above, it is mandatory to use a thermal storage system. The capacity of such system shall be able to provide at least 25% of the total plant production capacity for 4 hours during the peak load period from 12 pm – 4 pm with figure of merit (FOM) of 0.85 or above, (i.e., 0.25x4xX, where X is the plant production capacity after applying diversity). For governmental buildings, the cool storage capacity shall be able to provide at least
50% of the total plant production capacity for the same period. The consulting office shall provide a daily building load profile that forms the basis for his design strategy.
All air conditioned spaces shall have a minimum quantity of ventilation air that is the highest of the following values:
1. ASHRAE 62.1 Standard (Ventilation for Acceptable Indoor Air Quality) 2. 0.250 ACH for pressurization + exhaust air from kitchens, toilets and other areas.
