High-flow, high-level, low-profile, flat faced swirl diffuser with adjustable discharge direction for optimised cooling and heating in high spaces. 

Patent-pending features include:

• High volume flow rate: size DN1000 provides the highest airflow available on the commercial market.
• Helical guide-ring with vanes: provides full horizontal-to-vertical adjustment at a low and substantially constant pressure loss (duct pressure distribution is unaffected by diffuser discharge direction).
• Compact, shallow design: facilitates co-ordination in restricted ceiling void applications.
• Discharge direction adjustment options:
  • manual (standard)
  • thermal actuator (with bias adjustment)
  • electric (2-position or modulating)

Suitable for installation flush with ceiling or free-hanging from high discharge heights in applications such as foyers, art galleries, auditoria, convention spaces, exhibition halls, sports complexes, distribution centres and warehouses.

	Location – above: Discharge height: 2.5 – 15 m Flush with a closed ceiling or freely suspended
	Mixed flow discharge: 70 – 4000 L/s (250 – 14,400 m³/h) Nominal diameters: DN250 – DN1000
	Return air: suitable for use as a return air inlet.
	Adjustable direction/pattern: variable horizontal-to-vertical discharge direction adjustment.
	Manual adjustment: discharge direction adjustment is manual.
	Circular face shape: face diameter ≥ 1.4 x DN, suitable for vertical, round ducting or an exposed connection box (cylindrical or square). Well suited to plaster board ceilings or freely suspended applications.
	Radial face pattern: flush-face, offset-radial vane pattern matches SMARTEMP Fixed Helical Swirl Diffuser (HSC-FD), Helical Vari-Swirl Diffuser (HSC-VS) and Multi-Swirl Diffuser (MSC-FD).
	Metal Face: Powder coated galvanised steel.

Options

	Electric adjustment: 24V AC/DC, 2-10 V electric actuator.
	Thermal adjustment: wax element actuator, supply temperature powered, with manual bias adjustment.
	Sweat Inhibitor: thermally insulated face hub.
	Square face shape: lay-in tile (sizes DN250 to DN500 only) suitable for standard ceiling grids of up to 600 x 600 mm2 or 24″ square.
	Mounting Frame: suitable for framing a square ceiling cut-out (HSC-AD-DN250-S_to_DN500-S only).
	Plenum: square side-entry rigid foam or metal connection box (the latter optionally cylindrical), with acoustic lining opposite spigot on request.
	Metal Face: stainless steel (for selected sizes only).

SMARTEMP Adjustable Helical Swirl Diffuser HSC-AD

Available in selected markets as the LTG Helix-Deckendrallauslass ILH

Smarter Design / Smarter Engineering / SMARTAIR DIFFUSION™

The SMARTEMP Adjustable Helical Swirl Diffuser, type HSC-AD, alters air direction via a helically adjustable guide ring with vanes, which – unlike variable blade pitch adjustment – produces a substantially constant and low pressure loss across the full discharge pattern adjustment range. The patent-pending low profile helical twist design varies the airflow direction from a radially projecting horizontal swirl pattern, for draught-free cooling, to a downward penetrating swirl cone, for effective heating from a high level. High induction swirl discharge is realised in both cooling and heating modes to maximise comfort.

Multiple diffuser sizes are available for low to very high volume flow applications.

The SMARTEMP Adjustable Helical Swirl Diffuser is well suited to cooling and heating spaces with high discharge heights, such as foyers, halls, convention spaces and distribution centres.

Substantially constant-pressure variable air pattern adjustment is achieved via an assembly of 20 adjustable guide-vanes attached to a guide-ring that translates helically over 20 visible fixed swirl blades that form the flush diffuser face. The adjustable vanes and guide-ring are substantially hidden from view behind a flat diffuser face comprising off-set radial vanes flush with the surrounding diffuser edge, which may be round (for all DN sizes) or square (sizes DN250 to DN500 only).

Air pattern control may be manual (all sizes), or via thermally or electrically operated actuators or electrical adjustment.

Each thermally operated actuator includes a self-acting thermal wax-bulb that alters discharge direction in response to supply air temperature. No external power source or controls are required. Thermal wax-bulb bias may be pre-set or altered on site to suit the discharge height, airflow rate and temperature range on hand.

Each electrical actuator includes a 24 V AC/DC actuator with 2-10 V analogue control input. (Other actuator types are available on request.)  Diffuser electrical discharge direction adjustment is typically modulated by an output from the BMS (by others) in response to the supply-to-room air temperature differential. Electrical discharge direction adjustment is recommended in preference to thermal wax-bulb adjustment where significant room temperature fluctuations are likely (eg heating from a low night setback room temperature) and/or where discharge height is extremely high (eg where the supply-to-room heating temperature differential is low).

Thermal insulation of the diffuser hub is optionally available to minimise the risk of room air condensation in humid or high infiltration applications.

The diffuser may be flush mounted in a ceiling or freely suspended (ie no Coanda effect attachment to the ceiling required).

Each consecutive reduction in diffuser neck size reduces the diffuser airflow duty by approximately 50%. Additionally, each neck size is optionally available with a neck reducer and reduced guide ring, which reduce the diffuser airflow duty by approximately 30%. Consequently, diffuser duty reduces consecutively across the entire range in compound airflow steps of approximately 30%.

The SMARTEMP HSC-AD is made of powder coated galvanised steel. The flat central hub and 20 off-set radial swirl vanes form a substantially flush surface with the surrounding diffuser face. The helical twist design of the swirl vanes, whereby the pitch of the swirl vanes steepens towards the centre, allows increased airflow rates to be discharged (providing high capacity) and reduces the minimum permissible airflow rate (for low noise applications). Adjustable swirl blades attached to a guide-ring that traverses a helical path slide over fixed swirl vanes, providing stable, constant pressure, air pattern adjustment. This unique adjustable discharge direction design ensures substantially constant pressure characteristics regardless of diffuser discharge direction pattern, and enhances heating penetration when the air pattern is directed downwards.

High induction swirl discharge is achieved for all discharge patterns. This provides many advantages, including the provision of enhanced draught-free comfort with uniform temperature distribution in both cooling and heating applications. Intense mixing at the diffuser discharge surface strongly dilutes the supply air stream, mixing in large quantities of room air. Highly inductive swirl discharge provides rapid temperature equalisation of the supply air stream with room air.

In cooling mode, high induction prevents cold supply air from dumping. Uniform temperature distribution and high comfort levels are achieved (no cold and draughty or hot and stagnant spots). High induction also produces a strong increase in the supply air stream mass flow rate, as well as rapid discharge velocity decay, making the SMARTEMP HSC-AD swirl diffuser well suited to both long throws (due to the high momentum of the supply air stream) and short throws (due to its low velocity).

In heating mode, high induction produces low velocity downward projection of the strongly diluted, gently swirling warm supply air stream over considerable discharge heights. The supply of warmth to the space is gust-free, providing uniform temperature distribution and avoiding draughty spots interspersed by zones of stagnation.

Substantially constant pressure discharge direction adjustment ensures that changes to the airflow direction setting do not disturb air balancing and do not cause fan surging.

The SMARTEMP HSC-AD diffuser is suitable for substantially CAV systems in which ΔT_supply-room ≥ ‑13 K in cooling mode and ≤ +15 K when heating. This large volume flow rate, high induction, variable air pattern swirl diffuser is well suited to large volume spaces with high ceilings or large discharge heights. Enhanced levels of draught-free comfort are achieved, in which the air diffusion performance index (ADPI) typically exceeds 90%.

SMARTEMP Adjustable Helical Swirl Diffuser HSC-AD

Available in selected markets as the LTG Helix-Deckendrallauslass ILH

Smarter Design / Smarter Engineering / SMARTAIR DIFFUSION™

Patent-pending features include:

• Low profile – facilitates installation in restricted spaces.
• High capacity at low pressure drop – fan energy savings.
• Substantially constant pressure drop – maintains system air balance regardless of discharge direction setting.

SMARTEMP HSC-AD registered designs, patent applications and granted patents are listed at smartemp.com/patents.

SMARTEMP Adjustable Helical Swirl Diffuser HSC-AD

Available in selected markets as the LTG Helix-Deckendrallauslass ILH

Smarter Design / Smarter Engineering / SMARTAIR DIFFUSION™