In general, the discriminant is an algebraic expression that gives. information about the roots of a polynomial. In the case of a quadratic equation the discriminant is the part of. the quadratic equation that is under the radical sign.
How to Select Dampers and Louvers. Dampers and louvers are used to control the flow of air in a process system or enclosed area. Dampers are usually motorized or manually-adjustable for flow control. Louvers are often fixed for a constant flow rate.
90 Degree Louver. This is a movable blade louver, adjustable from closed to 90 degrees open. It is used to control the flow of air in or out of a building by varying how far the slats or opened. When the slats are in the 90-degree position the resistance to air flow is at a minimum offering maximum airflow.