A Study on the Structural Performance and the Design of Propeller Root Fillet Surfaces having nT-T/n section

nT-T/n 단면형상을 갖는 프로펠러 뿌리 필렛의 구조 성능 분석과 설계방안에 관한 연구

  • Received : 2015.07.30
  • Accepted : 2015.09.04
  • Published : 2015.10.20


The blade root fillets which have strong influences on the performance of propellers in the both structural and hydrodynamic points of view, are mechanical parts for smooth connection surface with a blade and a hub. A few related researches (Sabol, 1983; Kennedy, 1997) have noted that 3T-T/3 double radius section design would be suitable for reducing Stress Concentration Factor(SCF) and increasing Cavitation Inception Speed(CIS). In this paper, it is confirmed that this compound cross-section design has come close to the optimum solution in the shape optimization standpoint so that it could protect the propeller blade under the frequent and various loading cases. On that basis, we suggest the definite and simple fillet design methodology that has the cross-section with nT-T/n compound radius and elliptic shape which could sustain the given derivatives information as well as the offsets at the boundary and all inner region of the fillet surface. In addition, the result of design is presented in form of IGES file format in order to connect with NC machine seamlessly.


Fillet surface design;Cavity Inception Speed(CIS);Stress concentration factor;Constrained least squares approximation method


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