Weathering & Airflow Performance
Conventional louvres offer a balanced design, combining a high free area (around 50%) with good all round weather protection. Standard weather louvres may often meet the necessary weathering performance requirements, particularly in exhaust or simple screening applications where weather ingress, under most conditions, may be quite limited. For air intake or other more sensitive applications, where limiting water ingress is important, then a higher performance louvre can be an important design consideration. This is especially true for intake louvres where airborne carry over of water is an inevitable danger for units in exposed areas or that experience high wind or rain factors such as in marine or coastal zones.
The traditional approach to high performance louvre design has been to bank conventional louvre panels into double or even triple bank assemblies. Whilst effective, in practice this does incur significant penalties which, on the physical side, include depth, weight and handling and on the performance side a greatly increased pressure loss. Doubling or tripling the louvre in this way also, naturally, incurs cost.
In contrast our WH Series represent a radical new departure in terms of high performance louvres offering a simple single bank louvre assembly with outstanding weather resistance. Little removed from a standard louvre unit in terms of physical size or weight, testing in accordance with European Standard EN13030 for weather louvre performance shows the WH unit for example to be 99.5% effective in screening/exhaust applications and 99% effective even with face velocities of up to 1m/sec.
The performance graphs illustrates the effectiveness of our louvre under differing selection parameters. All testing was conducted in accordance with European Standard EN 13030 ie: simulated conditions of 13m/sec (30mph) wind speed with heavy rain @75mm/hr.
Louvre Design Elements
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