An experimental and CFD study on the effects of different pre-swirl ducts on propulsion performance of series 60 ship. (1st February 2019)

• Record Type: Journal Article
• Authors: Nowruzi, Hashem; Najafi, Amin
• Is Part Of: Ocean engineering. Volume 173(2019)
• Page Start: 491
• Page End: 509
• Publication Date: 2019-02-01
• Subjects: Pre-swirl duct -- Self-propulsion test -- Propulsion performance -- CFD; Ocean engineering -- Periodicals; Ocean engineering; Periodicals; 620.4162
• DOI: 10.1016/j.oceaneng.2019.01.007
• Languages: English
• ISSNs: 0029-8018

Abstract

Abstract: In the present paper, the effects of three different pre-swirl ducts on propulsion performance of a series 60 ship in comparison to the case with no duct are explored experimentally by self-propulsion test measurements and CFD analysis. To this accomplishment, Mewis duct, Becker twisted fins and unconventional half circular ducts are considered. For investigating the propulsion performance, thrust and torque coefficients, efficiency components of the intended propulsion system, wake and pressure distributions are evaluated. Based on our tests, the highest thrust and torque coefficients are achieved at lower advance ratios for Becker twisted fins, while; Mewis ducts provided the highest value of thrust and torque coefficients at higher advance ratios. Maximum value for propeller behind hull efficiency, relative rotative efficiency and propulsive efficiency are obtained with respect to unconventional half circular duct, Mewis duct, and the case with no pre-swirl duct. Based on the wake distribution analysis, local deformation on the upstream wake induced by pre-swirl ducts is detected. Moreover, it is found that the vortex shedding from trailing edges of the propeller blades has led to a defection on the downstream wake field.