Analysis on flow separation characteristics of last stage blade in steam turbine under small volume flow condition

Cao, Lihua; Wang, Wenlong; Luo, Hong; Hu, Pengfei; Li, Zhengwen; Zhang, Yanjun; Ma, Ting

doi:10.2298/tsci180904025c

Cited by 3 publications

(4 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…From Figure 8A-D, it can be found that the transitional windage condition of LSAT stage 2 occurs at about 33%M d with almost 40% π tt.d , this mass flow rate of transitional windage condition is similar to the study 13,17,34 in LP steam turbines the last stage during windage, even though LSAT and steam turbines working with different fluid and the ways of causing low load are different. Besides, the sharp decline in η tt of stage 2 during transitional windage is also similar to that in LP steam turbines' last stage.…”

Section: Global Aerodynamic Performancesupporting

confidence: 64%

“…However, there is complex threedimensional flow in rotor passages during windage. As shown in Figure 20B, two distinct vortices can be captured easily and are known as separation vortex and back flow vortex in steam turbine [34][35][36] but their mechanism and characteristic are not exactly the same as that in a steam turbine.…”

Section: The Flow Structure Of Rotors During Windagementioning

confidence: 99%

See 1 more Smart Citation

Flow characteristics of last‐segment axial turbine adopted in compressed air energy storage system under low load and windage conditions

Huang

Zhu

Wang

et al. 2022

Intl J of Energy Research

View full text Add to dashboard Cite

show abstract

Section: Global Aerodynamic Performancesupporting

confidence: 64%

Section: The Flow Structure Of Rotors During Windagementioning

confidence: 99%

Flow characteristics of last‐segment axial turbine adopted in compressed air energy storage system under low load and windage conditions

Huang

Zhu

Wang

et al. 2022

Intl J of Energy Research

View full text Add to dashboard Cite

show abstract

“…In order to accommodate renewable energy power generation, the coal-fired power generating units are forced to operate for a long time under low mass flow conditions. 1 The operating state of LPC deviates from the design condition for a long time under low mass flow conditions. As the load decreases, the inlet steam mass flow of LPC decreases.…”

Section: Introductionmentioning

confidence: 99%

Analysis on strength performance of the last stage blade in steam turbine under low mass flow conditions

Wang

Shi

Cao

et al. 2022

Proceedings of the Institution of Mechanical Engineers, Part C:

Self Cite

View full text Add to dashboard Cite

Under low mass flow conditions, the velocity field and temperature field are very complicated in the low-pressure cylinder (LPC) of steam turbine, which seriously affects the safe operation of blades. In order to study the safety of the last stage blade under low mass flow conditions, the non-equilibrium condensation model is used to numerically simulate the flow of low-pressure cylinder. The strength performance of the last stage rotor blade is analyzed by the fluid–solid coupling method. The results show that the vortex appears in the flow passage as the load decreases. The last two stages are most affected by the vortex. Under low mass flow conditions, the exhaust steam temperature of LPC rises. Under 5% low-pressure turbine heat-acceptance (LPTHA) condition, the temperature rise has affected the last three stage blades. The maximum temperature is located at the tip exit edge of suction surface of stator blade of the last stage. With the load decreasing, the maximum equivalent stress and maximum deformation show the law of first decreasing and then increasing. Under 10% low-pressure turbine heat-acceptance condition, the maximum equivalent stress is 827.96 MPa, which is over the design value. Under 5% LPTHA condition, the maximum deformation is 6.6301 mm, which is also far beyond the design value. The research results can provide a reference for the operation of steam turbine under low mass flow conditions.

show abstract

“…Drózdz (2021) from the view of boundary layer, the relationship between Reynolds number and flow separation is discussed. Cao (2019) studied the effect of flow rate on flow separation of last stage blade of steam turbine. The results show that the flow separation vortices appear near last stage blade at 30% of the rated volume flow.…”

Section: Introductionmentioning

confidence: 99%

Structure and Topology Analysis of Separated Vortex in Forward-Swept Blade

Liang

Zhou

et al. 2021

Front. Energy Res.

View full text Add to dashboard Cite

Flow separation commonly affects the stability of turbomachines, especially under low-flowrate conditions. Compared with conventional blades, a forward-swept blade is more efficient at high flowrates. However, experiments and numerical simulations show that a forward-swept blade produces an unstable region under low flowrate. In this paper, the topological analysis is used to analyze the structure and size of flow separation in forward swept blades. Three-dimensional structure and formation mechanism of vortices in forward-swept blades are analyzed using the cross-section flow pattern method. For forward-swept blades, flow separation mainly occurs at the blade tip and corner, accompanied by clear velocity fluctuations, the break-up of shed vortices, and diffusion. With decreasing flowrate, the shedding vortices move forward and the speed of vortex annihilation gradually decreases. In addition, the number of singularities in the rotor passage increases with the decrease of flow rate, and the region affected by shedding vortex increases. The rotating direction of internal vortex in turbomachinery is fixed. The pressure surface, passage vortex, and concentrated shedding vortex were found to rotate clockwise, whereas the suction surface, corner vortex, and shedding vortex rotate in a counterclockwise direction.

show abstract

Analysis on flow separation characteristics of last stage blade in steam turbine under small volume flow condition

Cited by 3 publications

References 18 publications

Flow characteristics of last‐segment axial turbine adopted in compressed air energy storage system under low load and windage conditions

Flow characteristics of last‐segment axial turbine adopted in compressed air energy storage system under low load and windage conditions

Analysis on strength performance of the last stage blade in steam turbine under low mass flow conditions

Structure and Topology Analysis of Separated Vortex in Forward-Swept Blade

Contact Info

Product

Resources

About