The figure below is a schematic illustration of a building elevator shaft/elevator. Assume that the elevator...

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The figure below is a schematic illustration of a building elevator shaft/elevator. Assume that the elevator ascends with a constant velocity V = Velev. The elevator weight when full is W. Assume the elevator shaft is a square cross section of dimensions wxw. Assume that the elevator has a height dimension, h. Also assume that the elevator shaft is enclosed, i.e. it is a closed system. Determine: a) Using the Navier-Stokes equation as a starting point, find the expression for viscous forces due to the air gap between the elevator and the shaft. How does the viscous force change as a function of air gap width for for a given ascent velocity Velev? b) What is the expression for the total force on the elevator to move at this velocity? What could be done to increase/decrease the elevator force? c) How might we change the elevator design to reduce the effects of viscous drag on the elevator? d) Insert some reasonable numbers into your expressions for the different variables and determine whether the calculated viscous forces are important or not. Higher Press. FORCE The figure below is a schematic illustration of a building elevator shaft/elevator. Assume that the elevator ascends with a constant velocity V = Velev. The elevator weight when full is W. Assume the elevator shaft is a square cross section of dimensions wxw. Assume that the elevator has a height dimension, h. Also assume that the elevator shaft is enclosed, i.e. it is a closed system. Determine: a) Using the Navier-Stokes equation as a starting point, find the expression for viscous forces due to the air gap between the elevator and the shaft. How does the viscous force change as a function of air gap width for for a given ascent velocity Velev? b) What is the expression for the total force on the elevator to move at this velocity? What could be done to increase/decrease the elevator force? c) How might we change the elevator design to reduce the effects of viscous drag on the elevator? d) Insert some reasonable numbers into your expressions for the different variables and determine whether the calculated viscous forces are important or not. Higher Press. FORCE