Can someone tell me how does flow rate still remain constant when Q=VA? Shouldnt the flow rate increase as Velocity increases. And how is this related to Bernoulli's.

 

Please show Bernoulli's equation to which you refer.

 

The question is asked without context. The Bernoulli equation states that when flow enters a restriction the flow will increase because the mass flow must be constant. The mass will decrease but the energy of at the restriction stays the same due to the kinetic energy of the flow.

Q=VA work in general but sometimes the oil is compressed so the volume moving through a boundary may change but the mass is constant.