NUMERICAL INVESTIGATION OF THE FLOW IN A MICRONOZZLE FOR DISPENSING A HIGHLY VISCOUS SEALNT

고점성 밀봉제 인쇄용 마이크로 노즐 설계를 위한 유동해석

  • 박규진 (금오공과대학교 대학원 기계공학과) ;
  • 곽호상 (금오공과대학교 기계공학부) ;
  • 손병철 (금오공과대학교 대학원 기계공학과) ;
  • 김경진 (금오공과대학교 나노정밀부품소재인력양성사업단)
  • Published : 2007.12.31

Abstract

A theoretical and numerical investigation is performed on the flow in a micronozzle for precision-controlled sealant dispenser. The working fluid is a highly viscous epoxy used as sealant in producing LCD panels, which contains a number of tiny solid spacers. Flow analysis is conducted in order to achieve the optimal design of internal geometry of a nozzle. A simplified design analysis methodology is proposed for predicting the flow in the nozzle based on the assumption that the Reynolds number is much less than O(1). The parallel numerical computations are performed by using a CFD package FLUENT. Comparison discloses that the theoretical model gives a good prediction on the distribution of pressure and wall shear stress in the nozzle. However, the theoretical model has a difficulty in predicting the maximum wall shear stress as found in a limited region near edge by numerical computation. The theoretical and numerical simulations provide the good guideline for designing a dispensing micronozzle.

Keywords

References

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