The Exhaust Pulsation of Roots Vacuum Pumps

The exhaust pulsation of the Roots vacuum pump restricts the stability and reliability of pump operation. To effectively suppress exhaust pulsation, a design scheme for a Roots vacuum pump with a pressure-stabilizing chamber was proposed, and the chamber model was developed. Combining RNG k−ε turbulence model, dynamic grid technology, and multi parameter comparison, the influence of structural parameters such as the opening phase angle, opening width angle, and aspect ratio of the stabilizing chamber on pulsation characteristics was studied and analyzed. The optimal stabilizing chamber structural parameters for suppressing gas pulsation were obtained. Based on this, the exhaust characteristics of the Roots vacuum pump with a stabilizing chamber were compared against those of a traditional Roots pump. Results show that, compared with the direct-discharge pump, the outlet pressure pulsation coefficient and flow pulsation coefficient of the proposed design are reduced by 56.8% and 49.2%, respectively. The pressure stabilizing chamber effectively enhances the stability of the exhaust process and provides theoretical guidance for pulsation suppression in the Roots vacuum pump.