Effects of external disturbance on the flow development near the boundary of a work table

This thesis addresses the issue of flow development near the boundary of a work table within a clean room. The flow is subjected to periodic external disturbance, either through the pulsation of a source of mass at fixed location, or a moving vortex. The global system consists of a flat table in a parallel oncoming laminar flow. The source of the disturbance is located in the vicinity of the boundary layer. The strength of disturbance is limited in order to apply the quasi-steady boundary layer theory. Based on a quasi-steady assumption, a Thwaytes type integration was performed in order to evaluate the displacement thickness and the shear stress on the wall. A parametric study based upon the change of the pulsation, the location and the strength of the disturbance was included in the study. Thwaytes's deviation applied to unsteady cases proved to be successful, and worth being used in further developments.