Technical Booklet L Combustion Appliances and Fuel Storage Systems·Page 16
Equivalent area definition
Defines equivalent area as the area of a sharp-edged circular orifice that would pass the same air flow rate at the same pressure difference as the product being tested, typically smaller than geometrical free area.
Equivalent area – the area of a sharp-edged circular orifice which would pass the same air flow rate at the same applied pressure difference as the product or device being tested. The equivalent area of a simple ventilator should be less than the geometrical free area and for complex products may be significantly less.
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