Aerodynamics Flashcards
Density varies with _____ and _____.
Density varies with temperature and pressure.
Viscosity varies with _____.
Viscosity varies with temperature.
The standard atmosphere is defined from the perfect gas law. Write the equation for the perfect gas law.
For our purposes, the atmosphere can be regarded as a _____ gas of _____ composition that satisfies the _____ _____ _____.
How does water vapor affect the density of air?
Water vapor decreases the density of air (a very small amount).
Although the effect of water vapor on air density is very small, water vapor does have a significant effect on engine performance and supersonic aerodynamics.
What are the standard sea level properties for gravity, pressure, temperature, and density?
What are the regions of the atmosphere?
What is the equation for temperature below 36,089 ft?
Above 36,089 ft, the temperature is assumed to be _____.
What is the equation for kinematic viscosity?
What is the equation for Reynolds Number?
What is indicated airspeed?
What is calibrated airspeed?
What is true airspeed?
What information do we use in performance from aerodynamics?
Drag polar
Lift coefficient
What information do we use in performance from propulsion?
Thrust or Power
SFC
What are the four forces of flight?
A body immersed in an airflow will experience an Aerodynamic Force due to…
Pressure is affected by
Shear stress is affected by…
What assumptions does Euler’s Equation make to Bernoulli’s Equation?
Inviscid, steady flow
What is Euler’s Equation?
Is Bernoulli’s Equation valid for compressible flow?
No. It was derived from incompressible flow assumptions
What is the moment convention on an airfoil?
What is Buckingham Pi Theorem?
What is the equation for dynamic pressure?
Give the equation for Mach number
Give the equation for Reynolds Number based on chord length
What is the reference area, S, as wetted area?
What is the reference area, S, as planform area?
What is the reference area, S, as base area?
What is the center of pressure of an airfoil?
The center of pressure is the centroid of the distributed load where the forces act.
Why don’t we use the center of pressure as a reference point in aircraft dynamics?
Because the center of pressure changes with changes in angle of attack.
What is the aerodynamic center of an airfoil?
Draw and label the anatomy of an airfoil.
What do each of the digits mean in a 4 digit airfoil? ex. NACA 2412
What do each of the digits mean in a 5 digit airfoil? ex. 23012
What do each of the digits mean in a 6 digit airfoil? ex. 64-212
What is the design lift coefficient?
Draw and label all the parts of a generic lift curve slope
All positively cambered airfoils have _____ zero-lift angles of attack.
All positively cambered airfoils have negative zero-lift angles of attack.
How does Reynolds Number affect the lift-curve slope?
