ACTIVE FLOW CONTROL FOR REDUCTION OF UNSTEADY STATOR-ROTOR INTERACTION IN A TURBOFAN SIMULATOR

An applicator for applying joint compound or mud to wallboard has six embodiments with a head, a mud outlet and a mud hose. The applicator has a handle and a control valve for controlling the flow of mud. Each embodiment also has a screed on the head above the mud outlet which extends beyond the end of the head. The screed smoothes down the mud applied to the wall and wipes away any excess mud. The first embodiment has a fan-shaped head with baffles to define multiple flow ports. The second and third embodiments have a rectangular head and a pair of retractable corner stops which align the mud outlets flush with the corners of drywall sections. The third embodiment adds a dispersion mechanism for varying the width of the outlet. The fourth embodiment of the applicator has a wedge-shaped head and a V-shaped screed with flow ports in the sidewalls that are designed to apply mud to right-angled corners. The control valve of the final embodiment has a cylindrical core with a slot which selectively aligns with a slot in the mud chamber. The control valve is operated by a spring-biased lever which contacts the wall. The lever has a pair of arms and a wheel on each arm. The arms extend from an outer edge of the control valve past the mud outlet to automatically open flow when the head is pressed against the wall.