2. A large workshop is ventilated as shown. RI Ra Workshop Supply Fan Exhaust Fan (a) The pressure loss along duct section Re is 300 Pa at a volume flow rate of 3 m3/s. For duct section Ra the pressure loss is 425 Pa at a volume flow rate of 2.5 m3/s. The supply and exhaust fan have identical characteristics as given below. Find the pressure in the workshop and the corresponding supply air volume flow rate. Single Fan Characteristics: Volume flow rate (m3/s) 0 1 2 3 4 Total pressure rise (Pa) 750 755 730 590 275 (b) A site investigation shows that there is a loss of air from the workshop by exfiltration through an aperture that has a pressure loss of 125 Pa for a flow of 0.5 m /s. Sketch the equivalent network for the whole system and determine the pressure in the workshop, the supply and exhaust air volume flow rate. [Ans. (a) 180 Pa and 3.24 m3/s, (b) 68 Pa, 3.44 m3/s, 3.07 m3/s]