Question

Consider fully developed turbulent flow in a two-dimensional diffuser with plane walls. Estimate the opening angle of the diffuser for which the downstream pressure gradient is equal to zero.

Answer 1

● The below given diagram is of a plane wall two dimensional diffuser:-

Let, The length, N with opening angle, 2 and an aspect ratio of N/W1.

So the choice of Opening angle of the diffuser depends on the location of the separation point,
which would be expected to be at some distance measured from the inlet of the diffuser in example.
However, the position of the separation point is based on theoretical calculation using
numerical integration method.

After calculation of the point of separation we can determine the opening angle by experiments.