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Article
Publication date: 15 July 2021

Yang Liu, Qingwei Gong, Yongning Bian and Qinghui Suo

Hydrodynamic forces and efficiency of bare propeller and ducted propellers with a wide range of advance ratio (J) and attack angle (θ) are examined. The thrust and torque…

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Abstract

Purpose

Hydrodynamic forces and efficiency of bare propeller and ducted propellers with a wide range of advance ratio (J) and attack angle (θ) are examined. The thrust and torque coefficients and the efficiency are presented and discussed in detail. The present results give a reliable guidance to the improvement of the hydrodynamic characteristics of ducted propellers.

Design/methodology/approach

The effect of a duct on the hydrodynamic performance of the KP458 propeller is numerically investigated in this study. Finite volume method (FVM)-based simulations are performed for a wide range of advance ratio J (0 ≤ J ≤ 0.75) and attack angle θ of the duct (15° ≤ θ ≤ 45°). A cubic computational domain is employed in this study, and the moving reference frame (MRF) approach is adopted to handle the rotation of the propeller. Turbulence is accounted for with the RNG k-ε model. The present numerical results are first compared against available experimental data and a good agreement is achieved.

Findings

The simulation results demonstrate that the hydrodynamic forces and efficiency increases and decreases with J, respectively, at the same attack angle. In addition, it is demonstrated that the hydrodynamic forces and efficiency are both improved due to the presence of the duct, which eventually leads a better hydrodynamic performance at high advance ratios. It is further revealed that as the attack angle increases, the pressure difference between the suction- and pressure-surfaces of the propeller is also augmented, which results in a larger thrust. The wake field is more uniform at θ = 30°, suggesting that a higher efficiency can be obtained.

Originality/value

The present study aims to investigate the effect of a duct on the KP458 propeller subjected to uniform inbound flow. The relationship between the uniform incoming flow and the attack angle of the duct is mainly focused, and the design of the ducted propellers for any ship hull can be improved according to this relationship.

Details

Engineering Computations, vol. 39 no. 2
Type: Research Article
ISSN: 0264-4401

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Article
Publication date: 14 February 2025

Ranran Zhou, Jianzhong Xu, Jiaqi Zhai and Qingwei Kong

This study examines how responsible leadership drives sustainable reconfiguring in multi-tier supply chains, addressing the recognized challenges of implementing sustainable…

3

Abstract

Purpose

This study examines how responsible leadership drives sustainable reconfiguring in multi-tier supply chains, addressing the recognized challenges of implementing sustainable practices in complex, global value chains, particularly in the face of the management challenges posed by the high complexity of multi-tier supply chains.

Design/methodology/approach

Data were collected from 475 Chinese manufacturing firms between December 2023 and June 2024. Structural equation modeling with maximum likelihood estimation was used to assess linear relationships, followed by least-squares linear regression to verify model robustness. Neural network modeling was then applied to explore potential nonlinear relationships among variables.

Findings

The study empirically confirms that responsible leadership was a direct driver of sustainable reconfiguring, and social capital partially mediated the relationship between responsible leadership and sustainable reconfiguring. In addition, it was found that in highly complex supply chains, responsible leadership has a more significant driving effect on sustainable reconfiguring, i.e. supply chain complexity positively moderates the relationship between responsible leadership and sustainable reconfiguring.

Originality/value

This study contributes to the field by uniquely examining responsible leadership as a driver of sustainable supply chain reconfiguration, highlighting its role in resource acquisition through social capital from a resource dependence perspective. Unlike prior studies that treat supply chain complexity primarily as a management obstacle, this research uncovers its role as a “demand driver” in sustainable reconfiguration, offering fresh insights into complexity’s strategic impact. This approach provides a novel framework for understanding the nuanced pathways through which leadership style and situational factors collectively shape sustainable practices in supply chains.

Details

Business Process Management Journal, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1463-7154

Keywords

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