Product Overview
The SMARTEMP HSC-FD Fixed Helical Swirl Diffuser is designed for modern HVAC applications requiring high flexibility, low-temperature supply and variable-volume airflow. Its innovative design features radially offset, cambered-leading-edge vanes and a span-wise helical twist within a bell-mouth discharge, achieving exceptional induction and mixing of supply air even when turndown is significant.
Key Features
- Flush-face diffuser with fixed aperture and fixed blades — clean, architectural finish.
- VAV-optimised swirl vanes:
- Radially offset vanes bias airflow into the bell-mouth.
- Cambered leading edges improve airflow attachment and reduce likelihood of vane stall.
- Span-wise helical twist enhances airflow attachment into the bell-mouth for stable discharge.
- Bell-mouth discharge and swirl action generate strong Coanda effect, resulting in stable horizontal airflow even when supply air is turned down or at low temperature.
- High airflow capacity — up to 440 L/s (≈1584 m³/h) depending on size.
- Wide turndown range for VAV systems — able to operate down to about 25-28% of full flow at ΔTsupply-room ≈ -16 K, making it ideal for low-temperature supply (≥ 8 °C).
- Horizontal (radial) 360° discharge pattern with standard square face for ceiling grid installation (600 × 600 mm nominal) or round face variants for exposed ceilings.
- Suitable for both flush-ceiling mount and freely suspended applications (depending on variant).
Construction & Options
Manufactured from powder-coated galvanised steel (selected sizes with stainless steel option) the HSC-FD features fixed swirl vanes that are flush with the diffuser face, maintaining an architectural finish.
Optional accessories and variants include:
- Neck reducers to reduce the effective airflow of high-capacity models while preserving VAV range.
- Segment covers to convert the discharge pattern from full 360° to 270°, 180° or twin 90° outlets for directional control.
- CleanScreen™ option: a perforated hub that delivers de-humidified or clean supply air to “wash” the diffuser face, reducing soiling, condensation and maintenance in high-humidity or high-pollutant environments (such as coastal, lobby or restaurant applications).
- Choice of face shapes: square lay-in tile format (DN250-DN500), round face (1.4×DN diameter) for vertical duct connections or exposed connection boxes.
Benefits in Application
- Excellent comfort performance: With high swirl induction the HSC-FD uniformly mixes supply air with room air, achieving rapid temperature equalisation and reducing draughts — even at low supply-air temperatures.
- Energy efficient: Low pressure drop and effective dispersion reduce fan energy and allow long throw or low velocity depending on room layout.
- Adaptable to variable-volume systems: The broad turndown performance makes it highly suited to VAV systems, especially with low-temperature supply (for example displacement or chilled-ceiling systems).
- Architectural integration: The flush finish and optional face patterns provide aesthetics compatible with modern ceiling designs and exposed grids.
- Retrofitting flexibility: The use of neck reducers and segment covers means the diffuser can be adapted to design changes or future fit-out modifications with minimal disruption.
Typical Specification
- Airflow range: 10 – 440 L/s (36 – 1584 m³/h) depending on size.
- Supply-air temperature suitability: ≥ 8 °C (with ΔTsupply-room approximately −16 K turndown).
- Discharge height: 2.4 – 4.5 m typical.
- Standard nominal diameters: DN250, DN355 and DN500.
