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The streamlines of the combined flow leads to the flow over a semi-infinite body and are obtained as,

(3.6.2)

The velocity field is obtained from stream function through differentiation i.e.

(3.6.3)

From the Fig. 3.6.1, it is clear that the flow becomes stagnant at some point because the velocity due to the source will cancel with that of uniform flow. Hence, a stagnation point is created which is obtained by assigning the velocity components to zero value in Eq. (3.6.3).

(3.6.4)

Solving for , the coordinates of stagnation point ‘B' is found out i.e. and the distance , directly upstream of the source. It may be observed that the point ‘B' will be blown further downstream, if source strength is increased keeping same, and increasing , keeping source strength same. When the coordinates of ‘B' is substituted in Eq.(3.6.1), the streamline ‘ABC' passing through the stagnation point is obtained i.e.

(3.6.5)

Since, , it follows that the equation of the streamline passing through the stagnation point is obtained from Eq. (3.6.1) as follows;

(3.6.6)