Research on Energy Dissipation Mechanism of Hump Characteristics Based on Entropy Generation and Coupling Excitation Mechanism of Internal Vortex Structure of Waterjet Pump at Hump Region
Year: 2025
Type: article
Abstract: High-speed mixed-flow and axial-flow pumps often exhibit hump or double-hump patterns in flow–head curves. Operating in the hump region can cause flow disturbances, increased vibration, and noise in pumps and systems. Variable-speed ship navigation requires waterjet propulsion pumps to adjust speeds. Speed transitions can lead pumps into the hump region, impacting efficient and quiet operation. This paper focuses on mixed-flow waterjet propulsion pumps with guide vanes. Energy, entropy production, and flow characteristic analyses investigate hump formation and internal flow properties. High-speed photography in cavitation experiments focuses on increased vibration and noise in the hump region. This study shows that in hump formation, impeller work capacity decreases less than internal fluid loss in the pump. These factors lead to an abnormal increase in the energy curve. The impeller blades show higher pressure at peak conditions than in valley conditions. Valley conditions show more pressure and velocity distribution variance in impeller flow passages, with notable low-pressure areas. This research aids in understanding pump hump phenomena, addressing flow disturbances, vibration, noise, and supporting design optimization.
DOI: 10.3390/jmse13030442
Authors: Min Liu, Yun Long, Hong Yin, Chenbiao Tian, Jinqing Zhong
Institutions: Wuhan Ship Development & Design Institute, Jiangsu University
Language: English
Subfield: Mechanics of Materials
Field: Engineering
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $3,137
OpenAlex ID: W4407963385