Application of CFD to the optimal design of an energy-saving pneumatic vacuum pad

Abstract

Paper presented at the 5th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, South Africa, 1-4 July, 2007.

This paper is concerned with the development of a new energy-saving vacuum pad using CFD-technique. Nowadays, application of pneumatic vacuum pads may be found in many different real industries, especially in the field of automatic conveyer system, automatic assembly line, semiconductor industry as well as silicon wafer factory, etc. Traditional vacuum pads generally utilize nozzles to create the effect of vacuum. In this paper, however, a new idea to generate the effect of vacuum is proposed by designing a structure similar to that of an aerostatic bearing. In details, the air is guided to flow through an optimally designed restrictor inside the vacuum pad and flow out through the outlet between the vacuum pad and the sucked work-piece. Therefore, according to Bernoulli’s equation, the air pressure near the center line of the vacuum pad decreases because of the increased airflow velocity. Consequently, the effect of vacuum is generated. To achieve two preset requirements, that is, large suction force output and low air consumption, the commercial CFD-RC software is utilized to simulate the air flow field and design the optimal geometry inside the vacuum pad. Experimental results further prove that the new vacuum pad with two preset features is successfully developed and implemented in this study.