(b)
Figure 6 Flow properties at mid-span for positions 0, 1, 2, 3, 4: a) Velocity; b) Static pressure
Figure 7 depicts the evolutions of static pressure around IGV vane and rotor blade with different positions of frozen-rotor. The distribution of static pressure on IGV blade looks in some extent similar for all positions expect there are small variations at trailing edge. For the rotor there are noticeable variations in pressure (loading) on both sides of blade which become clearer beyond 60 % of chord and more towards the blade trailing edge from both sides due to wakes interaction. The wakes of different vanes traverse differently the blades passages and are chopped into segments by the downstream blade row, and do not periodically envelop the rotor blades and behave as a negative jet impinging on the leading edge of blades, hence altering the inlet flow angle and the boundary layers and subsequently the aerodynamic loading of blades is drastically affected.