Abstract
Fluid flow analysis was carried out to estimate the fluid velocity in the vacuum suction casting process or vacuum fluidity test. A pressure equation was derived by assuming piston flow in a vertical cylindrical tube for simplicity and was numerically solved. The fluid velocity was considerably affected by some factors such as the pressure difference between the tube and reservoir, flow resistance of air path, and tube diameter. An oscillation of the fluid occurred at a higher velocity because of its high inertia. The calculated results showed good agreement with the experimental results by water or mercury. In the case of fluid without solidification, this model can be applied to estimate the effects of the above factors on the fluid velocity.
