Design Journal Entry - Module 9

Updated: I refined the arrangements of the ducts on each floor, zoning and cooling and heating CFMs are left same

LEVEL 1 HVAC

LEVEL 2 HVAC

LEVEL 3 HVAC

LEVEL 4 HVAC

3D

Top View

Side View

Duct Size Selection

After careful consideration between the 12x12 and 12x18 duct sizes for the project, I ultimately decided to go with the 12x12 size. This decision was driven by several key factors. Firstly, the 12x12 ducts are better suited to maintain the optimal air velocity required for our space, ensuring efficient air distribution and temperature control without the risk of noise issues associated with higher air velocities. Additionally, the smaller size offers greater flexibility in terms of installation, especially in constrained spaces where larger ducts could pose a challenge. This choice also aligns well with our cost considerations, as the 12x12 ducts are more economical not only in terms of initial material costs but also regarding the overall system efficiency. Ultimately, the 12x12 duct size proved to be the most practical and efficient choice for meeting my specific HVAC needs while also providing the best balance between performance, noise control, and cost-effectiveness.

Air Diffusers / Ducts

Following the placement of the supply diffusers, the next step involved designing the duct system to efficiently connect these diffusers. In planning the ductwork layout, a crucial consideration was the elevation at which the ducts and diffusers would be positioned. The ducts were designed with a middle elevation of 14 feet, while the diffusers were set at an elevation of 13 feet. This arrangement was carefully chosen considering that each level in the building has a ceiling height of 15 feet. This design ensures that there is sufficient space above the occupied zone for the ducts and diffusers, facilitating optimal airflow distribution without impeding the aesthetic or functional use of the space. This strategic placement is integral to maintaining the efficiency of the HVAC system while adhering to the architectural constraints of the building.

Mechanical Zones

I wanted to have same arrangement of zones on every floor.

In designing the HVAC system for our building, I've taken into account several crucial factors to ensure optimal comfort, efficiency, and adaptability across all spaces.

1. Occupancy Patterns: I've analyzed how different areas within the building are utilized throughout the day and week. This allowed me to identify varying needs between spaces like conference rooms, offices, and lobbies, adjusting zoning to match their specific occupancy schedules and densities.
2. Building Orientation and External Influences: Recognizing the impact of our building's orientation, I've accounted for the varying solar heat gains across south-facing and north-facing zones. This understanding helps in tailoring cooling needs more precisely. Additionally, external elements such as shade, wind, and reflections have been considered to refine our HVAC approach further.
3. Internal Heat Gains: Acknowledging the diverse internal heat gains from occupants, equipment, and lighting, especially in high-density areas, has been key. This insight ensures that spaces with substantial equipment use are adequately cooled, maintaining a balanced environment throughout the building.
4. Thermal Comfort Requirements: Different activities and spaces within our building demand unique thermal conditions. From the cooler needs of data centers to the slightly warmer and more ventilated environments of gym areas, I've customized the HVAC zoning to meet each space's specific thermal comfort criteria effectively.

The building is split into two main types of zones: the west and east zones, which are mirrors of each other, and two central zones that share similar properties.

For the west and east zones, they house identical room types, including conference rooms, exhibition spaces, education rooms, and private offices. The rationale behind grouping these similar spaces into their respective zones is twofold. Firstly, it allows for tailored temperature and airflow control that matches the specific activities and occupancy patterns expected in these rooms. Conference rooms and private offices, for instance, require different ventilation rates and temperatures compared to exhibition and education spaces, which may have varying occupancy and equipment use. Secondly, despite their similar internal configurations, the east and west orientations necessitate slight adjustments in HVAC settings to compensate for the differing amounts of solar gain each side receives during the day, ensuring consistent comfort levels throughout.

The central zones are characterized by their exposure to sunlight and encompass hallways, open spaces, and lobbies. These areas, being central, do not have the same type of external walls as the east and west zones but are instead surrounded by the building itself, affecting their thermal characteristics. The central zones are designed to manage the solar gain through the roof and internal heat gains from people moving through or congregating in these spaces. By grouping the hallways, open spaces, and lobbies into their zones, the HVAC system can be optimized to handle higher air volumes and cooling needs, addressing the unique challenges posed by these communal and transitional areas.

Challenges:

My primary challenge was diving zones appropriately, as the shape and room arrangement was not enabling me to divide it into four or three zones, so as a result I have four mechanical equipments, two have similar zone properties and other two are also for other similar zone properties.

There are several rooms where Cooling Airflow is surprisingly high, I need to doublecheck what is the reason behind this.

To do:

Done

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