Under the right weather conditions, wind can align with advertising billboards, presenting an excellent opportunity to...

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Under the right weather conditions, wind can align with advertising billboards, presenting an excellent opportunity to examine a real-world occurrence of boundary layer flow over a flat plate. Consider a cold (p = 2.469 x 10-3 slug ‚µ = 3.60 × 10-7¹bf²5) windy day with 20 mph ft3, air blowing across a 48 ft long billboard. A novice engineer (probably in a different fluids class) calculates the drag force on the billboard using a Blasius boundary layer. You decide to check the applicability of this calculation. a) Estimate the drag coefficient assuming a Blasius boundary layer. b) Calculate the expected location x (from the leading edge) of the turbulent transition of the boundary layer, assuming transition occurs at Rex,cr = 5 x 105. c) Assuming the boundary layer is a laminar Blasius boundary layer up to the point of transition, what is the boundary layer thickness at the location found in part b? d) Assuming transition to a turbulent boundary layer occurs at Rex,cr = 5 x 105, estimate a proper drag coefficient for the given flow. e) Cite an equation, table, or figure part d. which was used for the estimate in Under the right weather conditions, wind can align with advertising billboards, presenting an excellent opportunity to examine a real-world occurrence of boundary layer flow over a flat plate. Consider a cold (p = 2.469 x 10-3 slug ‚µ = 3.60 × 10-7¹bf²5) windy day with 20 mph ft3, air blowing across a 48 ft long billboard. A novice engineer (probably in a different fluids class) calculates the drag force on the billboard using a Blasius boundary layer. You decide to check the applicability of this calculation. a) Estimate the drag coefficient assuming a Blasius boundary layer. b) Calculate the expected location x (from the leading edge) of the turbulent transition of the boundary layer, assuming transition occurs at Rex,cr = 5 x 105. c) Assuming the boundary layer is a laminar Blasius boundary layer up to the point of transition, what is the boundary layer thickness at the location found in part b? d) Assuming transition to a turbulent boundary layer occurs at Rex,cr = 5 x 105, estimate a proper drag coefficient for the given flow. e) Cite an equation, table, or figure part d. which was used for the estimate in Under the right weather conditions, wind can align with advertising billboards, presenting an excellent opportunity to examine a real-world occurrence of boundary layer flow over a flat plate. Consider a cold (p = 2.469 x 10-3 slug ‚µ = 3.60 × 10-7¹bf²5) windy day with 20 mph ft3, air blowing across a 48 ft long billboard. A novice engineer (probably in a different fluids class) calculates the drag force on the billboard using a Blasius boundary layer. You decide to check the applicability of this calculation. a) Estimate the drag coefficient assuming a Blasius boundary layer. b) Calculate the expected location x (from the leading edge) of the turbulent transition of the boundary layer, assuming transition occurs at Rex,cr = 5 x 105. c) Assuming the boundary layer is a laminar Blasius boundary layer up to the point of transition, what is the boundary layer thickness at the location found in part b? d) Assuming transition to a turbulent boundary layer occurs at Rex,cr = 5 x 105, estimate a proper drag coefficient for the given flow. e) Cite an equation, table, or figure part d. which was used for the estimate in

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a For a Blasius boundary layer over a flat plate the drag coefficient is approxim... View the full answer