Final 303

What assumptions do we need for energy equation for 2D gas dynamics

No flow is called _____ flow

What type of nozzles can have shock diamonds?

What isentropic operation on the particle must we perform for total/stagnation parameters? (6 p3 v11.0)

What isentropic operation on the particle must we perform for sonic parameters? (6 p3 v11.0)

What isentropic operation on the particle must we perform for maximum/infinite parameters? (6 p3 v11.0)

What type of nozzle has exhaust plumes?

What equation should we use for a choked nozzle?

What equation should we use for a not-choked nozzle?

If along an isentropic streamline which parameters can be directly computed

Flow is ____ with a concave nozzle if A* = A min

Flow is __ is diverging nozzle, if pb/p0,1 < pcrit1

if pb/p0,1 > pcr,1

if pcr,2 < pb/p0,1 < pcr,1

if pb/p0,1 = pcr,1

if pb/p0,1 = pcr,2

T or F: pcr,2 is your start and unstart condition

Is all subsonic flow isentropic?

to properly start a tunnel, we want pb/p0,1 <= ____?

T or F: Sliplines move towards areas of higher pressure

For non-choked converging nozzle, what equation do we use to find the mass flow?

For a non-choked diverging nozzle, what relation do we use to find the mass flow?

T or F: The higher the Mach number, the higher the pressure ratio?

Shock downstream exit tunnel starts if pb/p0,1 _ pcr,2

Shock downstream exit tunnel unstarts if pb/p0,1 _ pcr,2 (enter a greater than or equal sign)

What are wave reflections?

Compression theory

What thin airfoil theory

How does exact compression/expansion theory compare to TAF?

How does exact TAF theory compare to compression/expansion?

Is this a thin airfoil?

Is this a thin airfoil?

Cones beta angle will be smaller because of what 2 factors?

immediately behind the shock created by a cone you can assume it is ___ and ____?

Is this a thin airfoil?

Shocks coming off of thin airfoils are going to be _____ and not ____

T or F: If you have a blunt body, you end up with a bow shock somewhere in front of the stagnation point

Which assumptions do we use for prandtl-meyer?

What laws do we need to derive the prandtl-meyer relation?

Compression shocks are ___

expansion shocks are ____

Direction of vorticity

T or F, the boundary layer is NOT adiabatic

The gradient of entropy points towards the ___ every time?

T or F: velocity near the symmetry line is always smaller than when it is far away

T or F: moving shocks are always unsteady

T or F: shocks are always unsteady

If Prandtl-Meyer function were valid in the case of a trivial solution, it makes the most physical sense that ___?

What is the definition of the camber line?

Tick the single box that indicates the fundamental law that forms the basis for the transport equation for the density. Options are Mass conservation, Newton’s 2nd law, or 1st law of thermodynamics

Tick the single box that indicates the fundamental law that forms the basis for the transport equation for the flow velocity. Options are Mass conservation, Newton’s 2nd law, or 1st law of thermodynamics

Tick the single box that indicates the fundamental law that forms the basis for the transport equation for the specific internal energy. Options are Mass conservation, Newton’s 2nd law, or 1st law of thermodynamics

Tick the single box that indicates the fundamental law that forms the basis for the transport equation for the specific kinetic energy. Options are Mass conservation, Newton’s 2nd law, or 1st law of thermodynamics

Tick the single box that indicates the fundamental law that forms the basis for the transport equation for the specific total energy. Options are Mass conservation, Newton’s 2nd law, or 1st law of thermodynamics

What 4 things do we assume to use the method of characteristics in specific form

Briefly explain what the statement “(V dot nabla) s” means

What conditions are necessary for ( V dot nabla) s = 0?

With the change from irrevesible requirement to irrotational, only ____ and ____ are anisentropic

Consider the flow through a (strong) stationary shock wave. What conditions are required for (V dot nabla) s to equal 0

What assumption(s) are necessary to assume vorticity to be constant along streamlines:

Assume that the velocity vector V points to the left and the vorticity vector points out of the page. What is the direction of the entropy gradient delta s?

Crocco’s theorem tells us these flow condition(s) imply isentropic flow (options are steady, adiabatic, irrotational, or reversible flow)

In which flow regime(s) do we find the maximum entropy?

In which flow regime(s) do we find the minimum entropy?

Tick the flow region(s) that support rotational flow

What is the direction of the entropy gradient, nabla s, in the region(s) of the diagram that supports rotational flow?

In which direction does the vorticity vector point?

What is the delta? Options: initial mach-wave angle, terminating Mach-wave angle, flow-deflection angle with respect to an arbitrary horizontal coordinate, flow-deflection angle with respect to the flow immediately upstream of the considered compression/expansion fan

What determines the sign of delta?

Can we use the Prandtl-Meyer equation to solve subsonic-flow problems and why?

the method of characteristics, in the specific form in which we derived and applied it, is restricted to

Pick one or more applicable answers for the method of characteristics from the following interdependent options: (2D flow, axisymmetric flow, full 3D flow)

Pick one or more applicable answers that we can use the method of characteristics on from the following independent options: (subsonic, sonic, or supersonic flow)

Is the method of characteristics valid for the calculation of the flow through a strong shock wave? why?

In the expressions for the Riemann invariants: K = nu +- delta, what is delta?

In our derivation of the Method of Characteristics, we approximate Mach waves as (increasingly more) piecewise-linear line segments. In which of the unknown variables does this approximation produce an error?

Using exact theory, calculate the pressure coefficient corresponding to region 5, Cp,5

What does it mean for a pressure coefficient to be negative

In the definition of Cp, why do we use the freestream, dynamic pressure Q infinity?

Next, let’s discuss the flow downstream of the trailing edge. An educated guess is that the flow downstream of the TE is aligned with the freestream direction. Based on the given direction, how should the slip line be deflected to improve our assumption for the slip line’s direction

Using thin airfoil theory consider the geometries shown below and assuming M1 and angle of attack are the same for all, how do the lift coefficients of these airfoils relate? Explain

Using thin airfoil theory consider the geometries shown below and assuming M1 and angle of attack are the same for all, how do the drag coefficients of these airfoils relate?

What assumptions do we need to use thin airfoil theory?

If the thin airfoil assumption is/assumptions are justified, what can we say about the angles of shock waves and expansion fans? They:

Can we treat the airfoil below as a thin supersonic airfoil?

In the formula for the pressure coefficient corresponding to thin airfoil theory: Cp = 2delta/sqrt(M²-1). Which Mach should be used?

The zero reference for the flow deflection angle delta:

Change in entropy through Mach waves is …?

While increasing pb, which of the geometries will support underexpanded flow last?

while increasing pb, which of the geometries will unstart last?

While increasing pb, which of the geometries will support choked flow last?

while increasing pb equally slowly for each of the geometries and setting Amin equal for all geometries, which of the geometries do we expect to have drained the reservoir the most as we land at sea level?

What column of NACA 1135 can you NOT use to calculate for a pitot tube problem