Freestream Vector

We are now ready to define some basic terms and concepts, and to summarize several results which we can use. The first is the idea a "freestream vector". Imagine an airplane flying. From the point of view of those sitting in it, the whole atmosphere is flowing towards and past it. The speed of this flow is the freestream speed. If we wanted to measure it, we would have to make sure that we made the measurement where the air flow has not been modified by the presence of the aiplane. The freestream speed may be different from the speed at which the airplane seems to be flying when viewed from the ground, because there may be winds. The direction of the freestream will be different if the aiplane is climbing or descending, or if there is an updraft or downdraft in the local winds. All of these ideas are captured below.

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Next Page →
Next Page →
← Previous Page
← Previous Page