Numerical investigation of the effect of axial clearance on the last stage of marine turbine

Shu, Peng; Sun, Tao; Yu, Qingrui; Li, Guoping; Yu, Wanbo; Shi, Zhenyi

doi:10.1016/j.oceaneng.2022.112711

Cited by 7 publications

(2 citation statements)

References 30 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The research shows that, as the radial clearance of the blade cascade decreases, the predicted efficiency of the hydraulic turbine decreases. Shu P et al [20] studied the effect of the axial clearance between the static cascades of marine steam turbines on the flow field and found that, as the axial clearance increases, the blade pressure fluctuation decreases, but the vortex structure at the blade root increases, resulting in a decrease in unit efficiency.…”

Section: Introductionmentioning

confidence: 99%

Numerical Study on the Effect of Crown Clearance Thickness on High-Head Pump Turbines

Li,

Yan,

Liu

et al. 2023

Water

View full text Add to dashboard Cite

In order to promote the development of new power systems and the consumption of clean energy, pumped storage hydropower stations tend to become increasingly larger in capacity and higher in head height. In this paper, a three-dimensional model of the full channel of a high-head pump turbine is established, and the influence of the gap thickness between the runner crown and the headcover on the internal flow field characteristics, pressure fluctuation characteristics and axial water thrust are studied by means of computational fluid dynamics (CFD). The results indicate that the area where the pressure and velocity vary greatly in the flow field of the crown clearance is at the seal of the labyrinth ring. In addition, the pressure balance pipe has a greater impact on the pressure and flow rate of the water passing through the clearance, and the crown clearance near the pressure balance pipe generates a vortex, resulting in energy loss. Decreasing the thickness of the clearance has no obvious effect on the pressure on the flow-passing components, and increasing the thickness of the clearance has a great change in the pressure values at the upper crown inlet, in front of the labyrinth ring of the crown and in front of the labyrinth ring of the band. The upper part of the vaneless area, the crown inlet and the lower ring inlet are close to the runner; hence, the interference from the rotating parts is the strongest. The effect of increasing the thickness of the crown clearance on the axial water thrust is greater than that of decreasing the thickness of the crown clearance. The pulsation frequency of the axial thrust on the crown, band and blade and the resultant force of the axial thrust increase with the increase in the crown clearance thickness.

show abstract

Section: Introductionmentioning

confidence: 99%

Numerical Study on the Effect of Crown Clearance Thickness on High-Head Pump Turbines

Li,

Yan,

Liu

et al. 2023

Water

View full text Add to dashboard Cite

show abstract

“…The research results of Shu et al indicated a significant effect of the axial clearance on the flow field. When the axial clearance increases, the pressure fluctuation amplitude on the blade surface decreases significantly, but the instability strengthens, and the efficiency decreases slightly as the axial gap increases [11]. Li et al conducted a numerical study on the influence of axial gap changes on turbines.…”

Section: Introductionmentioning

confidence: 99%

Numerical and Experimental Investigation on Flow Field of the Turbine Stage under Different Axial Gaps

et al. 2023

View full text Add to dashboard Cite

In order to reduce efficiency losses and improve the aerodynamic efficiency of axial turbines used in industry, the flow fields of the turbine stage were investigated numerically and experimentally under different axial gaps in this work. The influence of the axial gaps on the flow unsteadiness and the flow field distribution is discussed. The results show that the aerodynamic efficiency of the turbine stage increases when the axial distance is reduced. The difference in entropy increases under different axial distances are mainly found in the section from the stator inlet to the rotor inlet: the turbine not only has a better time-average aerodynamic performance, but also has a better transient aerodynamic performance under working conditions with a small axial distance. Additionally, the maximum disturbance amplitudes of the stator and rotor are located near the trailing edge of the stator and the leading edge of the rotor, respectively. Compared with the wake disturbance of the upstream stator to the downstream adjacent rotor, the reverse disturbance of the downstream stator to the adjacent upstream rotor is more sensitive to the change in the blade spacing.

show abstract

Numerical simulation of the relationship between steam flow excitation characteristics and coverage on the governing stage of marine steam turbine

Sun,

Liu,

et al. 2024

Ocean Engineering

View full text Add to dashboard Cite

Numerical investigation of the effect of axial clearance on the last stage of marine turbine

Cited by 7 publications

References 30 publications

Numerical Study on the Effect of Crown Clearance Thickness on High-Head Pump Turbines

Numerical Study on the Effect of Crown Clearance Thickness on High-Head Pump Turbines

Numerical and Experimental Investigation on Flow Field of the Turbine Stage under Different Axial Gaps

Numerical simulation of the relationship between steam flow excitation characteristics and coverage on the governing stage of marine steam turbine

Contact Info

Product

Resources

About