Answer Happy

Question 6 (a) The drag coefficient for an object depends on many parameters such as, Shape dependence, Reynolds number and compressibility. Discuss briefly each parameter with illustrated figures. (5 marks) (b) Consider a wind turbine with two 10 cm diameter cups with a centre-to-centre distance of 35 cm, as shown in figure 6-b. The pivot is stuck as a result of some malfunction, and the cups stop rotating. For a wind speed of 20 m/s and air density of 1.25 kg/m3, determine the maximum torque this turbine applies on the pivot. The drag coefficients for a hemispherical cup when the hemispherical and plain surfaces are exposed to wind flow are is 0.4 and 1.2, respectively. Determine the maximum torque this turbine applies on the pivot? (15 marks) 35 cm Figure 6-b (c) Discuss the flow characteristics of nonadiabatic, adiabatic, non-isentropic and isentropic flow fields? (5 marks)