Introduces a new method for simulating HVAC duct systems termed the T-method. It predicts flow rates and pressures throughout a duct system. The results of the calculation are flow rate and pressure resistance of each section, pressure at each node and an operating point on the fan performance curve. Supplies a problem definition, a theoretical approach, calculation procedures and numerous examples.

KEYWORDS: Calculating, ducts, flow rate, air flow, pressure, fans, performance, heating, designing, ventilation, air conditioning.