scholarly journals Analysis of the Impacts of Bearing on Vibration Characteristics of Rotor

2017 ◽  
Vol 2017 ◽  
pp. 1-7 ◽  
Author(s):  
Peiji Yang ◽  
Qi Yuan ◽  
Chao Huang ◽  
Yafeng Zhou ◽  
Hongliang Li ◽  
...  

Aiming at a Top Gas Recovery Turbine Unit (TRT) with double support rotor and the extending disk end, theoretical and experimental analysis about influence of cylindrical bearing and four-lobe bearing on vibration of TRT rotor system are conducted in this paper. The results indicate that vibration of the rotor supported by cylindrical bearing is more stable than that supported by four-lobe bearing at the driving end (DE) and the nondriving end (NDE). The amplitude of rotor is supported by both of these types of bearing increases as the speed increases at the NDE, while the amplitude of the DE remains unchanged. Comparing with the result of theoretical analysis, the practical test results are more consistent with the theoretical response analysis conducted by applying unbalanced mass at the extending disk end. This paper presents an analysis method of the critical characteristics of a double support rotor system with the extending disk end and provides reference value for dealing with vibration fault of double support rotor system with the extending disk end.

1984 ◽  
Vol 106 (1) ◽  
pp. 10-17 ◽  
Author(s):  
K. Yoshida ◽  
M. Ozaki ◽  
N. Oka

A linear response analysis method of the tension leg platform (TLP) subjected to regular waves is proposed. In this analysis method, flexibility of the superstructure can be taken into account in the equations of motion; response motions, tension variations of tendons and structural member forces are solved simultaneously. The applicability of this method is confirmed by comparison with the test results on two kinds of small-scale TLP models. The structural responses obtained from these calculations and their effects on tension variation of tendons are studied. Finally, several kinds of structural response characteristics are conclusively discussed.


2018 ◽  
Vol 6 (1) ◽  
Author(s):  
Nuridin, SE., MM. ◽  
Dwi Ardika Prayudha

This research is aimed to examine the influence of brand image and product quality to car purchase decision at PT. Mitsubishi Krama Yudha Motors and Manufacturing. Data analysis method was used, is quantitative analysis, by using validity and reliability test, coefficient of determination, and multiple linear regression analysis. Result of regression equation is: Y = 0,665 + 0,517 X1 + 0,416 X2 Simultaneously testing of brand image variables and product quality to purchase decision, shown by F count equal to 85,955 bigger than F table 3,159 or with sig. F 0.000 is smaller than alpha 0.005. Based on the test results simultaneously, can be seen that the independent variables (brand image and product quality) have a positive and significant impact on the car purchase decision at Mitsubishi cars At PT. Krama Yudha Motors and Manufacturing. Suggestions which can be given for future developments and determinations of policy are, companies should pay attention to brand image, product quality, to make customers more satisfied and keep using Mitsubishi cars as their choice.


Author(s):  
Hao Li ◽  
Haipeng Geng ◽  
Bo Wang ◽  
Wei Zheng

In this paper, a rotordynamic experiment on a compressor rotor system is presented and the feasibility of gas foil bearings with inhomogeneous bump foils is verified. A push–pull device is designed to obtain the stiffness curve and the nominal clearance of foil bearings. Operating points and dynamic coefficients of the rotor system at each rotating speed are predicted. In rotordynamic analysis, an alternative model of the impeller is proposed and the critical speed is predicted by employing the finite element method, in which the dynamic coefficients of inhomogeneous foil bearings are taken into account. Compared with the experimental result, the accuracy of the prediction for the critical speed is verified to be about 14% error. Two sets of foil bearings with 22 and 41 μm nominal clearance are manufactured and tested. Test results indicate that the vibration amplitude can be greatly reduced by diminishing the bearing clearance. When foil bearings with 22 μm clearance are used, the high-order harmonic frequencies of rotor vibration are significantly inhibited, and the amplitude of the rotating frequency is obviously restricted. Thus, the foil bearing with inhomogeneous bump foils tested in this paper can meet the speed requirement of the compressor when the nominal clearance is set at 22 μm.


1983 ◽  
Vol 105 (3) ◽  
pp. 480-486 ◽  
Author(s):  
M. Sakata ◽  
T. Aiba ◽  
H. Ohnabe

In the field of rotor dynamics, increased attention is being given to the transient response analysis of the rotor, since the effects of impact loading and vibrations of the rotor arising from blade loss can be studied by a time transient solution of the rotor system. As recent trends in rotating machinery have been directed towards lightweight, high-speed flexible rotors, the effect of flexibility on transient response analysis is becoming of increasing importance. In the present paper, a transient vibration analysis is carried out on a flexible-disk/flexible-shaft system or rigid-disk flexible-shaft system subjected to a sudden imbalance that is assumed to represent the effect of blade loss. To solve the basic equation governing a rotating flexible disk the Galerkin’s method is used, and the equation of motion of the rotor system is numerically solved by employing the Runge-Kutta-Gill’s method. Experiments were conducted on a model rotor having a blade loss simulator; the shaft vibrations were also measured. The validity of the anaytical results was demonstrated by comparison with the experimental results.


2011 ◽  
Vol 2-3 ◽  
pp. 785-790
Author(s):  
Jong Hyen Baek ◽  
Yong Kyu Kim ◽  
Jae Ho Lee ◽  
Hyen Jung Jo

For the purpose of improving the future domestic train control systems and securing interoperability, according to the global development trends of train control systems, it is presented that the test results of interoperability between wayside train control systems installed in existed line, and the onboard train control system. Due to the safety-critical characteristics of train systems, the site test in the section where the wayside equipment is installed may lead to a danger against safety. Therefore, by way of constructing a simulation environment of train control systems, the T/R data systems of the equipment for interoperability are confirmed and the interoperability test are obtained by applying these systems to onboard equipment.


2018 ◽  
Vol 4 (4) ◽  
Author(s):  
Hidekazu Takazawa ◽  
Kazuma Hirosaka ◽  
Katsumasa Miyazaki ◽  
Norihide Tohyama ◽  
Naomi Matsumoto

A new Japanese nuclear regulation involves estimating the possible damage to plant structures due to intentional aircraft impact. The effect of aircraft impact needs to be considered in the existing nuclear power plants. The structural damage and fuel dispersion behavior after aircraft impact into plant structures can be evaluated using finite element analysis (FEA). FEA needs validated experimental data to determine the reliability of the results. In this study, an analysis method was validated using a simple model such as a cylindrical tank. Numerical simulations were conducted to evaluate the impact and dispersion behavior of a water-filled cylindrical tank. The simulated results were compared with the test results of the VTT Technical Research Centre of Finland (VTT). The simulations were carried out using a multipurpose FEA code LS-DYNA®. The cylindrical tank was modeled using a shell element, and the tank water was modeled using smoothed particle hydrodynamics (SPH) elements. First, two analysis models were used to evaluate the effect of the number of SPH elements. One had about 300,000 SPH elements and the other had 37,000 SPH elements. The cylindrical tank ruptured in the longitudinal direction after crashing into a rigid wall, and the filled water dispersed. There were few differences in the simulated results when using different numbers of SPH elements. The VTT impact test was simulated with an arbitrary Lagrangian-Eulerian (ALE) element to consider the air drag. The analytical dispersion pattern and history of dispersion velocity ratio agreed well with the impact test results.


ETIKONOMI ◽  
2013 ◽  
Vol 12 (1) ◽  
Author(s):  
Indayani Indayani ◽  
M Nur Yahya

The aim of this study is to determine and examine the influence of cash position, debt to equity ratio, and growth potential to the dividend payout ratio of companies listed in Indonesia Stock Exchange (BEI). The analysis method of the data used to test the hypothesis is the multiple linear regressions. The test result showed that simultaneous cash position, debt to equity ratio, and growth potential did not significantly influence the dividend payout ratio at manufacturing companies listed on the BEI. The test results showed that only partially variable cash position that significantly influence the dividend payout ratio of companies listed on the Stock Exchange, while variable debt to equity ratio, and growth potential does not affect the dividend payout ratio of companies listed on the BEIDOI: 10.15408/etk.v12i1.1904


Author(s):  
W. Schmitt ◽  
V. Thomas

The first part of this paper describes the test installation of the gas turbine and the compressor in the workshop, test execution, measuring methods, evaluation and measuring uncertainties. The second part of this paper describes the site installation, execution of the test under full load conditions on natural gas, measuring methods, evaluation and measuring uncertainties. The third part of this paper compares both the measurements and the Reynolds number correction which was used for the evaluation of the pipeline compressor test results in the workshop.


2020 ◽  
Vol 2 (1) ◽  
pp. 21-32
Author(s):  
Syaiful Pakaya

This study aims to determine how much influence work culture and leadership partially and simultaneously on the work discipline of employees at the Gorontalo City Education Office. The sampling method used in this study is the census method, namely the number of samples in the study is less than 100. The main point is through a list of statements  that are tested through validity and reliability tests. The analysis method used is the path analysis method. The first test results show that the variables of work culture (X1) and leadership (X2) have a simultaneous effect on employee work discipline. The results of testing the second hypothesis show that work culture (X1) partially has a positive and significant effect on employee work discipline. The third test results indicate that the leadership variable (X2) partially has a positive and significant effect on employee work discipline.


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