skkong001
Jan7-10, 06:09 AM
1. The problem statement, all variables and given/known data
The centre of pressure for a prototype vehicle under development is found to be 0.1m aft (in the horizontal plane) and 0.2m above (in the vertical plane) from the centre of gravity. The vehicle has a front cross section of 2.1m2 with current predictions of lift and drag coefficients of 0.15 and 0.4 respectively. Air density is 1.2kg/m3. For a cruising speed of 50mph:
Q1.Calculate the aerodynamic pitching moment (you may assume 1mph = 0.447m/s).
Q2.Does the vehicle pitch nose up or down?
Q3.Calculate the aerodynamic pitching moment coefficient assuming a wheelbase of 2.3m.
2. Relevant equations
Lift = 0.5 x ρ x vē x S x Cl
Drag = 0.5 x ρ x vē x S x Cd
Pitching moment = 0.5 x 0.5 x ρ x vē x S x Cp x l
The centre of pressure for a prototype vehicle under development is found to be 0.1m aft (in the horizontal plane) and 0.2m above (in the vertical plane) from the centre of gravity. The vehicle has a front cross section of 2.1m2 with current predictions of lift and drag coefficients of 0.15 and 0.4 respectively. Air density is 1.2kg/m3. For a cruising speed of 50mph:
Q1.Calculate the aerodynamic pitching moment (you may assume 1mph = 0.447m/s).
Q2.Does the vehicle pitch nose up or down?
Q3.Calculate the aerodynamic pitching moment coefficient assuming a wheelbase of 2.3m.
2. Relevant equations
Lift = 0.5 x ρ x vē x S x Cl
Drag = 0.5 x ρ x vē x S x Cd
Pitching moment = 0.5 x 0.5 x ρ x vē x S x Cp x l