Abstract
In the present paper, the change of flow structure such as the wall shear stress at the apex of the anterior communicating artery with the initiation of aneurysm is described in steady flow. The anterior communicating artery composing the circle of Willis is one of the predilection sites where the cerebral aneurysm occurs frequently. The flow field around the anterior communicating artery is simulated by two confluent tubes joining at the angle of 60 degrees, two parallel bifurcating tubes, and the junctional tube, bypass, connecting four tubes. The velocity profile is clarified around the apex where the cerebral aneurysm is apt to initiate. In particular, the gradient of wall shear stress around the apex at one confluent tube with much flow rate is estimated, and the relation between the change of wall shear stress and the initiation of aneurysm is discussed physiologically.
