A 6-m exhaust duct is to be installed vertically for ventilation purposes. An engineer must decide...

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A 6-m exhaust duct is to be installed vertically for ventilation purposes. An engineer must decide whether to choose a cylindrical cross section or a square cross section for the duct. The maximum wind velocity in the localities is 30 m/s. Use the density of air as 1.177 kg/m³ and the viscosity as 18.46 x 10-6 N.s/m². a. b. C. Determine the Reynolds number for the flow for the cylindrical cross section if the diameter is 0.11 m. Determine the drag force exerted on the duct. Use FIGURE A2 to estimate the drag coefficient of the duct. [10 marks] Compare the drag force exerted on the duct if a square cross section of width 0.11 m is used instead of the cylindrical cross section. If the wind is approaching the square duct at a 45-degree angle, how much increase or decrease in the drag force will be experienced by the duct? Justify your answer. [10 marks] Describe a counter measure to reduce the drag on the duct if a cylindrical cross section is used. [5 marks] A 6-m exhaust duct is to be installed vertically for ventilation purposes. An engineer must decide whether to choose a cylindrical cross section or a square cross section for the duct. The maximum wind velocity in the localities is 30 m/s. Use the density of air as 1.177 kg/m³ and the viscosity as 18.46 x 10-6 N.s/m². a. b. C. Determine the Reynolds number for the flow for the cylindrical cross section if the diameter is 0.11 m. Determine the drag force exerted on the duct. Use FIGURE A2 to estimate the drag coefficient of the duct. [10 marks] Compare the drag force exerted on the duct if a square cross section of width 0.11 m is used instead of the cylindrical cross section. If the wind is approaching the square duct at a 45-degree angle, how much increase or decrease in the drag force will be experienced by the duct? Justify your answer. [10 marks] Describe a counter measure to reduce the drag on the duct if a cylindrical cross section is used. [5 marks] A 6-m exhaust duct is to be installed vertically for ventilation purposes. An engineer must decide whether to choose a cylindrical cross section or a square cross section for the duct. The maximum wind velocity in the localities is 30 m/s. Use the density of air as 1.177 kg/m³ and the viscosity as 18.46 x 10-6 N.s/m². a. b. C. Determine the Reynolds number for the flow for the cylindrical cross section if the diameter is 0.11 m. Determine the drag force exerted on the duct. Use FIGURE A2 to estimate the drag coefficient of the duct. [10 marks] Compare the drag force exerted on the duct if a square cross section of width 0.11 m is used instead of the cylindrical cross section. If the wind is approaching the square duct at a 45-degree angle, how much increase or decrease in the drag force will be experienced by the duct? Justify your answer. [10 marks] Describe a counter measure to reduce the drag on the duct if a cylindrical cross section is used. [5 marks] A 6-m exhaust duct is to be installed vertically for ventilation purposes. An engineer must decide whether to choose a cylindrical cross section or a square cross section for the duct. The maximum wind velocity in the localities is 30 m/s. Use the density of air as 1.177 kg/m³ and the viscosity as 18.46 x 10-6 N.s/m². a. b. C. Determine the Reynolds number for the flow for the cylindrical cross section if the diameter is 0.11 m. Determine the drag force exerted on the duct. Use FIGURE A2 to estimate the drag coefficient of the duct. [10 marks] Compare the drag force exerted on the duct if a square cross section of width 0.11 m is used instead of the cylindrical cross section. If the wind is approaching the square duct at a 45-degree angle, how much increase or decrease in the drag force will be experienced by the duct? Justify your answer. [10 marks] Describe a counter measure to reduce the drag on the duct if a cylindrical cross section is used. [5 marks]

Answer rating: 100% (QA)

Solution a Reynolds number and drag force for a cylindrical cross section The Reynolds number is calculated as follows Re VD where is the density of a... View the full answer