High Suction Performance Pumps with Large Inlet Blade Angles and an Integrated Stability Control Device

2016 ◽  
Author(s):  
Ryan K. Lundgreen ◽  
Kerry Oliphant ◽  
Daniel Maynes ◽  
Steven E. Gorrell
Keyword(s):  
Stability Control ◽  
Control Device ◽  
Suction Performance ◽  
High Suction

Increasing Inducer Stability and Suction Performance With a Stability Control Device

2018 ◽  
Vol 141 (1) ◽  
Author(s):  
R. Lundgreen ◽  
D. Maynes ◽  
S. Gorrell ◽  
K. Oliphant
Keyword(s):  
Fluid Dynamic ◽  
Leading Edge ◽  
High Energy ◽  
Stability Control ◽  
Control Device ◽  
Design Flow ◽  
Flow Coefficient ◽  
Blade Tip ◽  
Rotordynamic Forces ◽  
Suction Performance

An inducer is used as the first stage of high suction performance pump. It pressurizes the fluid to delay the onset of cavitation, which can adversely affect performance in a centrifugal pump. In this paper, the performance of a water pump inducer has been explored with and without the implementation of a stability control device (SCD). This device is an inlet cover bleed system that removes high-energy fluid near the blade leading edge and reinjects it back upstream. The research was conducted by running multiphase, time-accurate computational fluid dynamic (CFD) simulations at the design flow coefficient and at low, off-design flow coefficients. The suction performance and stability for the same inducer with and without the implementation of the SCD has been explored. An improvement in stability and suction performance was observed when the SCD was implemented. Without the SCD, the inducer developed backflow at the blade tip, which led to rotating cavitation and larger rotordynamic forces. With the SCD, no significant cavitation instabilities developed, and the rotordynamic forces remained small. The lack of cavitation instabilities also allowed the inducer to operate at lower inlet pressures, increasing the suction performance of the inducer.

scholarly journals Reliability analysis of the security and stability control device based on the Monte Carlo method

2018 ◽  
Vol 145 ◽  
pp. 9-14 ◽  
Author(s):  
Xueming Li ◽  
Zengji Liu ◽  
Yi Tang ◽  
Xu Gao ◽  
Yingxin Ma ◽  
...  
Keyword(s):  
Monte Carlo ◽  
Monte Carlo Method ◽  
Reliability Analysis ◽  
Stability Control ◽  
Control Device ◽  
The Monte Carlo Method

The Influence of Transient Inlet Distortions on the Instability Inception of a Low-Pressure Compressor in a Turbofan Engine

2000 ◽  
Vol 123 (1) ◽  
pp. 1-8 ◽  
Author(s):  
Dirk C. Leinhos ◽  
Norbert R. Schmid ◽  
Leonhard Fottner
Keyword(s):  
Total Pressure ◽  
Delta Wing ◽  
Stability Limit ◽  
Stability Control ◽  
Control Device ◽  
Inlet Flow ◽  
Stall Inception ◽  
Hypersonic Aircraft ◽  
Surge Margin ◽  
Power Spectral

While studies on compressor flow instabilities under the presence of inlet distortions have been carried out with steady distortions in the past, the investigation presented here focuses on the influence of transient inlet distortions as generated by variable geometry engine intakes of super- and hypersonic aircraft on the characteristic and the nature of the instability inception of a LPC. The flow patterns (total pressure distortion with a superimposed co- or counterrotating swirl) of the distortions are adopted from a hypersonic concept aircraft. A LARZAC 04 twin-spool turbofan was operated with transient inlet distortions, generated by a moving delta wing, and steady total pressure distortions starting close to the LPC’s stability limit until it stalled. High-frequency pressure signals are recorded at different engine power settings. Instabilities are investigated with regard to the inception process and the early detection of stall precursors for providing data for a future stability control device. It turned out that the transient distortion does not have an influence on the surge margin of the LPC compared to the steady distortion, but that it changes the nature of stall inception. The pressure traces are analyzed in the time and frequency domain and also with tools like Spatial FFT, Power Spectral Density, and Traveling Wave Energy. A Wavelet Transformation algorithm is applied as well. While in the case of clean inlet flow, the compressor exhibits different types of stall inception depending on the engine speed, stall is always initiated by spike-type disturbances under the presence of steady or transient distortions. Modal disturbances are present in the mid-speed range that do not grow into stall, but rather interact with the inlet flow and produce short length scale disturbances. The obtained early warning times prior to stall are adversely affected by transient distortions in some cases. The problem of appropriate thresholding becomes evident. The best warning times have been acquired using a statistical evaluation of the Wavelet coefficients, which might be promising to apply in a staged active control system. This system could include different phases of detection and actuation depending on the current precursor.

scholarly journals The research of configuration for stability control device in smart substation

2021 ◽  
Vol 260 ◽  
pp. 02007
Author(s):  
Ye He ◽  
Binjiang Hu ◽  
Dongxu Chang ◽  
Jie Zhang ◽  
Lingfang Li ◽  
...  
Keyword(s):  
Stability Control ◽  
Control Device ◽  
Protection Device ◽  
Soft Switch ◽  
Operation And Maintenance ◽  
Technical Specifications ◽  
The Stability ◽  
Configuration Scheme ◽  
Smart Substation

A unified specification to design and operate the stability control device in smart substation has not been formed yet, which has greatly affected the promotion and application of stability control device in smart substation. Thus, referring to the technical specifications of protection device and combining to the specificity of stability control device, a full and detailed configuration scheme is proposed to meet the requirement, including the device configuration principle, the access configuration of SV and GOOSE for variable primary connection types, the virtual terminal and soft switch. This solution is beneficial to standardize the R&D of stability control device in smart substation, and to facilitate on-site debugging, operation and maintenance.

The Influence of Transient Inlet Distortions on the Instability Inception of a Low Pressure Compressor in a Turbofan Engine

2000 ◽  
Author(s):  
Dirk C. Leinhos ◽  
Norbert R. Schmid ◽  
Leonhard Fottner
Keyword(s):  
Total Pressure ◽  
Delta Wing ◽  
Stability Limit ◽  
Travelling Wave ◽  
Stability Control ◽  
Control Device ◽  
Inlet Flow ◽  
Stall Inception ◽  
Surge Margin ◽  
Power Spectral

While studies on compressor flow instabilities under the presence of inlet distortions have been carried out with steady distortions in the past, the investigation presented here focuses on the influence of transient inlet distortions as generated by variable geometry engine intakes of super- and hypersonic aircrafts on the characteristic and the nature of the instability inception of a LPC. The flow patterns (total pressure distortion with a superimposed co- or counter-rotating swirl) of the distortions are adopted from a hypersonic concept aircraft. A LARZAC 04 twin-spool turbofan was operated with transient inlet distortions, generated by a moving delta-wing, and steady total pressure distortions starting close to the LPC’s stability limit until it stalled. High frequency pressure signals are recorded at different engine power settings. Instabilities are investigated with regard to the inception process and the early detection of stall precursors for providing data for a future stability control device. It turned out that the transient distortion does not have an influence on the surge margin of the LPC compared to the steady distortion, but that it changes the nature of stall inception. The pressure traces are analysed in the time and frequency domain and also with tools like Spatial FFT, Power Spectral Density and Travelling Wave Energy. A Wavelet Transformation algorithm is applied as well. While in the case of clean inlet flow the compressor exhibits different types of stall inception depending on the engine speed, stall is always initiated by spike-type disturbances under the presence of steady or transient distortions though modal disturbances are present in the mid speed range that do not grow into stall, but rather interact with the inlet flow and produce short lengthscale disturbances. The obtained early warning times prior to stall are adversely affected by transient distortions in some cases. The problem of appropriate threshholding becomes evident. The best warning times have been acquired using a statistical evaluation of the Wavelet coefficients which might be promising to apply in a staged active control system which could include different phases of detection and actuation depending on the current precursor.

The Application of Safety and Stability Control Device in Middle of Henan Power Grid

2013 ◽  
Vol 860-863 ◽  
pp. 2068-2072
Author(s):  
Li Hua Zhang ◽  
Hui Lin Wang ◽  
Hong Qing Gan
Keyword(s):  
Control System ◽  
Power System ◽  
Control Strategies ◽  
Stability Control ◽  
Control Device ◽  
The Other ◽  
Stable Operation ◽  
Secondary Line ◽  
Stability Control System ◽  
Safety And Stability

Safety and stability control device is the secondary line of defense of power system stable operation. Firstly, this paper proposed the requisite of the regional safety and stability control system installed in Wuzhou 500kV switching station and the other two stations which belonged to the middle Henan power system. And then, it presented the components and elaborated control strategies of the system. It listed the situations of the united testing, at last, it summarized notes of this safety and stability control system in daily operation.

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