Presentation on theme: "2. Describing the flow of air inside a duct."— Presentation transcript:
1 2. Describing the flow of air inside a duct. Air passes through a 10 inch-ID duct at 250F and 100 psig. The velocity is found to be uniform and equal to 25 ft/sec. Compute the mass flow rate (lbm/min) and the volumetric flow rate in acfm and scfm.
2 3. Pollutant concentration and emission rate. An exhaust vent from a plastics manufacturing plant discharges at 100 acfm of air at 200C, 90 kPa. A continuous emissions monitor shows that the discharge contains 5 ppm of phenol vapor. This value (5 ppm) is close to the odor threshold and the community can be expected to detect the medicinal, sweet odor of the phenol. The molecular weight of phenol is What is the actual phenol concentration in the exhaust stream, and what is the emission rate of phenol to the atmosphere?
3 4. The exhaust gas from an automobile contains 1 4. The exhaust gas from an automobile contains 1.5 percent by volume of carbon monoxide. What is the concentration of CO in milligrams per cubic meter (mg/m3) at 25C and 1 atm pressure? What is the concentration in ug/m3 in the exhaust pipe if it is at 200C and 1.1 atm of pressure?
4 5. The average daily concentration of sulfur dioxide is observed to be 415 ug/m3 at 25C and 1 atm. What is the concentration of SO2 in parts per million?
5 6. The ozone concentration is observed to be 118 ug/m3 at an urban monitoring stations. Does this value exceed the concentration found in standard dry air ( ppm)?
6 7. The maximum concentration of dust in the atmosphere during 24-hour period was found to be grains per dry standard cubic foot (gr/dscf). What is the equivalent concentration in micrograms per cubic meter? (1gr/ft3 equals to 2.29 g/m3)