scholarly journals Numerical Simulation of the Flow Structure in the Inlet Flow Duct Section of the Valve of Steam Turbine

2018 ◽  
Vol 0 (12) ◽  
Author(s):  
Artem Ivanovich Babayev ◽  
Lyubov Vladimirovna Kolodyazhnaya ◽  
Vladimir Nikolaevich Goloshchapov
Keyword(s):  
Numerical Simulation ◽  
Steam Turbine ◽  
Flow Structure ◽  
Inlet Flow ◽  
Flow Duct

scholarly journals Numerical Simulation of Intrachamber Processes in the Power Plant

2021 ◽  
Vol 11 (11) ◽  
pp. 4990
Author(s):  
Boris Benderskiy ◽  
Peter Frankovský ◽  
Alena Chernova
Keyword(s):  
Numerical Simulation ◽  
Power Plant ◽  
Flow Structure ◽  
Power Plants ◽  
Control Volume ◽  
Conjugate Problem ◽  
Topological Features ◽  
Gas Dynamic ◽  
Calculation Results ◽  
Volume Method

This paper considers the issues of numerical modeling of nonstationary spatial gas dynamics in the pre-nozzle volume of the combustion chamber of a power plant with a cylindrical slot channel at the power plant of the mass supply surface. The numerical simulation for spatial objects is based on the solution conjugate problem of heat exchange by the control volume method in the open integrated platform for numerical simulation of continuum mechanics problems (openFoam). The calculation results for gas-dynamic and thermal processes in the power plant with a four-nozzle cover are presented. The analysis of gas-dynamic parameters and thermal flows near the nozzle cover, depending on the canal geometry, is given. The topological features of the flow structure and thermophysical parameters near the nozzle cap were studied. For the first time, the transformation of topological features of the flow structure in the pre-nozzle volume at changes in the mass channel’s geometry is revealed, described, and analyzed. The dependence of the Nusselt number in the central point of stagnation on the time of the power plants operation is revealed.

scholarly journals Numerical simulation of argon flow structure in plasma vortex reactor

2018 ◽  
Vol 1112 ◽  
pp. 012020
Author(s):  
A I Klimov ◽  
S E Kurushina ◽  
N E Molevich ◽  
D P Porfiriev ◽  
I P Zavershinskii
Keyword(s):  
Numerical Simulation ◽  
Flow Structure ◽  
Argon Flow ◽  
Vortex Reactor

Simulation and Experimental Investigation of a New Type of Combined Seal Structure

2021 ◽  
Vol 143 (5) ◽  
Author(s):  
Jin Li ◽  
Xiaoli Fu ◽  
Shenglin Yan
Keyword(s):  
Numerical Simulation ◽  
Labyrinth Seal ◽  
Internal Resistance ◽  
Leakage Rate ◽  
Geometric Parameters ◽  
Inlet Flow ◽  
New Type ◽  
Leakage Characteristics ◽  
Nozzle Structure ◽  
Better Than

Abstract Based on the study of leakage characteristics of labyrinth seal structure (LSS), a new type of combined seal structure (CSS) consisting of the labyrinth structure and the nozzle structure has been proposed. The sealing characteristics of CSS and LSS are compared by means of numerical simulation and experiments, and the effects of the internal resistance of the device, structural geometric parameters and other factors on the leakage characteristics of CSS are studied. The results illustrate the following conclusions: (a) When the inlet flow is 12 m3/h and the internal resistance of the device is 2000–4000 Pa, the leakage rate of CSS decreases by 30%–40% in comparison with that of LSS, which indicates that the performance of CSS is much better than that of LSS. (b) The leakage rate increases as the internal resistance of the device increases. When the internal resistance of the device increases from 2000 Pa to 8000 Pa, the leakage rate increases from 26% to 72%. (c) When the internal resistance of the device is constant, the larger the inlet flow, the smaller the leakage rate. (d) The choice of nozzle radius in structural geometric parameters is more important for the leakage rate than the tooth height and teeth numbers. When the nozzle radius decreases, ΔPAB (pressure difference between the labyrinth structure and the nozzle structure) and the leakage rate decrease accordingly.

Effect of Initial Surface Roughness on Water Erosion Resistance of Last Stage Blade Substrate of Steam Turbine

2020 ◽  
Author(s):  
Fang Li ◽  
Shunsen Wang ◽  
Juan Di ◽  
Zhenping Feng
Keyword(s):  
Numerical Simulation ◽  
Surface Roughness ◽  
Steam Turbine ◽  
Water Droplet ◽  
Erosion Resistance ◽  
Water Erosion ◽  
Experimental Results ◽  
Initial Surface ◽  
Maximum Water ◽  
Last Stage

Abstract In order to study the effect of initial surface roughness on water droplet erosion resistance of last stage blade substrate of steam turbine, eight 17-4PH samples were grounded and velvet polished by different mesh metallographic sandpaper to establish sample with different initial surface roughness. The water droplet erosion experiments were carried out in the highspeed jet water erosion experiment system, and the mass and micro-morphology of each sample were measured by using precision electronic balance and ultra-depth of field microscope respectively at each experimental stage, and the measurement of water erosion trace width and maximum water erosion depth were also completed at the same time. On the basis of experiments, LS-DYNA was used for numerical simulation to verify the reliability of experimental results again. Results show that the smoother the initial surface of sample, then the smaller the mass loss, the stronger its water erosion resistance. On the contrary, the rougher the initial surface of sample, the more severe the surface irregularity, the more times the water droplets concentrated at the lowest point of pit when water droplets flow laterally after impact is completed, thus accelerating the formation of initial crack and lateral expansion, the poorer the water erosion resistance of sample. At same water erosion time, the smoother the sample surface, the later the complete erosion trace appear, the narrower the water erosion trace width. However, the maximum water erosion depth of sample is not affected by the initial surface roughness. The numerical simulation results are in good agreement with the experimental results.

Research on Fault Diagnosis of Steam Turbine Rotor Unbalance and Parallel Misalignment Based on Numerical Simulation and Convolutional Neural Network

2021 ◽  
Author(s):  
Chongyu Wang ◽  
Di Zhang ◽  
Yonghui Xie
Keyword(s):  
Neural Network ◽  
Numerical Simulation ◽  
Fault Detection ◽  
Steam Turbine ◽  
Turbine Rotor ◽  
Detection Accuracy ◽  
Steam Turbine Rotor ◽  
Parallel Misalignment ◽  
Coupling Fault ◽  
The Impact

Abstract The steam turbine rotor is still the main power generation equipment. Affected by the impact of new energy on the power grid, the steam turbine needs to participate in peak load regulation, which will make turbine rotor components more prone to failure. The rotor is an important equipment of a steam turbine. Unbalance and misalignment are the normal state of rotor failure. In recent years, more and more attention has been paid to the fault detection method based on deep learning, which takes rotating machinery as the object. However, there is a lack of research on actual steam turbine rotors. In this paper, a method of rotor unbalance and parallel misalignment fault detection based on residual network is proposed, which realizes the end-to-end fault detection of rotor. Meanwhile, the method is evaluated with numerical simulation data, and the multi task detection of rotor unbalance, parallel misalignment, unbalanced parallel misalignment coupling faults (coupling fault called in this paper) is realized. The influence of signal-to-noise ratio and the number of training samples on the detection performance of neural network is discussed. The detection accuracy of unbalanced position is 93.5%, that of parallel misalignment is 99.1%. The detection accuracy for unbalance and parallel misalignment is 89.1% and 99.1%, respectively. The method can realize the direct mapping between the unbalanced, parallel misalignment, coupling fault vibration signals and the fault detection results. The method has the ability to automatically extract fault features. It overcomes the shortcoming of traditional methods that rely on signal processing experience, and has the characteristics of high precision and strong robustness.

Research on the Numerical Simulation of Zoning Flood Retarding and Sand Silting of Flood Plain in the Lower Yellow River

2011 ◽  
Vol 243-249 ◽  
pp. 4576-4580
Author(s):  
Xiao Lei Zhang ◽  
Dong Po Sun ◽  
Jun Jie Li
Keyword(s):  
Numerical Simulation ◽  
Mathematical Model ◽  
Flow Structure ◽  
Yellow River ◽  
Flood Plain ◽  
Lower Yellow River ◽  
The Lower Yellow River ◽  
Water And Sediment ◽  
Set Up

The 2-D water and sediment mathematical model which reflects flood retarding and sand silting of flood plain in the Lower Yellow River has been set up in this paper. Through carrying on 2-D water and sediment numerical simulation of the “96.8” typical flood, the authors studied influence of zoning flood retarding and sand silting on flood travel, flow structure of floodplain-channel and transver exchange of water and sediment. The simulating results in different conditions show that, adopting the zoning flood retarding and sand silting in the Lower Yellow River effectively worked on retarding flood and sharpening peaks in the flood retarding basin, guaranteed and expanded transver exchange of water and sediment in the floodplain and channel and maintained the river channel’s vigor. This can relieve “secondary suspended river” states in the Low Yellow River to a certain extent.

Sign in / Sign up

Export Citation Format

Share Document