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REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
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Journal of the Korean Society of Tribologists and Lubrication Engineers
Journal Basic Information
Journal DOI :
The Korean Society of Tribologists and Lubrication Engineers
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Volume & Issues
Volume 20, Issue 6 - Dec 2004
Volume 20, Issue 5 - Oct 2004
Volume 20, Issue 4 - Aug 2004
Volume 20, Issue 3 - Jun 2004
Volume 20, Issue 2 - Apr 2004
Volume 20, Issue 1 - Feb 2004
Selecting the target year
Feasibility Verification of Cryogenic Ball Bearings for a Turbopump
Journal of the Korean Society of Tribologists and Lubrication Engineers, volume 20, issue 4, 2004, Pages 177~182
In a turbopump cryogenic ball bearings are used to carry static and hydraulic loads, and these ball bearings must stand up to high load and speed in cryogenic circumstance. Verification of bearing performance is crucial to successful development of a turbopump. In this paper, focusing on the turbopump under developing by KARI, the performances of 203 and 207 bearings are verified through the series of tests simulating the real operating condition of turbopump.
Experimental Study on the Leakage Performance Characteristics of Floating Ring Seal
Journal of the Korean Society of Tribologists and Lubrication Engineers, volume 20, issue 4, 2004, Pages 183~189
The floating ring seal is used in an oxidizer and a fuel pump of the turbo pump unit in the liquid rocket engine to optimize a leakage without rubbing phenomenon. The damper floating ring seal, one of the floating ring seals, is with round hole pattern surfaces. It can reduce the leakage by increased friction factor that obtained from experimental data. In this paper, the leakage test about floating ring seal and damper floating ring seal was conducted. The test result showed the leakage performance of damper floating ring seal was better than the leakage performance of floating ring seal. With the leakage test the lock-up and rotation test about seal was conducted and that position is measured. The relatively large lock-up eccentric ratio was obtained from the test result of damping floating ring seal. The attitude angle of seal increases with increasing of shaft rotation.
Subsurface Stress Analysis with the Consideration of Tangential Loading and Elasto-Hydrodynamic Lubrication
Journal of the Korean Society of Tribologists and Lubrication Engineers, volume 20, issue 4, 2004, Pages 190~196
The effect of tangential loading on the subsurface stress field has been investigated numerically. As tangential load increases, the subsurface stress field expands more widely to the direction of the tangential load. Places of the maximum shear stress and the maximum effective stress are getting closer to the surface with the increasing tangential load. The tangential load in an elasto-hydrodynamic lubrication condition is so low that it does not affect the subsurface stress field.
Disk Vibration Suppression with Air Bearing Concept
Journal of the Korean Society of Tribologists and Lubrication Engineers, volume 20, issue 4, 2004, Pages 197~203
As the rotational speed and the track density are increased, the vibration of disk/spindle system becomes critical issue in order to reduce the track mis-registration. In this work, we propose a simple inclined air bearing (20
20 mm) system which is located very near to the rotating poly-carbonate disk, and investigate suppressing effect for the disk vibration mode (0,0) both experimentally and numerically. We find dynamic stiffness and damping coefficients of air bearing and then apply those values to the disk vibration analysis. Numerical results show about 10 percent difference comparing to the experimental results. Also we investigate the reduction of disk vibration and power consumption with two different kinds of inclined bearing for the normal disk drive system experimentally. We find inclined air bearing can reduce about 30 percents of the transverse disk vibration.
Experimental Study on the Oil Leakage Characteristics of Valve Stem System
Journal of the Korean Society of Tribologists and Lubrication Engineers, volume 20, issue 4, 2004, Pages 204~208
This paper presents the oil leakage characteristics of the valve stem system in gasoline engines. For the oil leakage investigation, four study models have been prepared as functions of used poppet valve and used valve stem seal, used poppet valve and unused valve stem seal, unused poppet valve and used valve stem seal, and unused poppet valve and unused valve stem seal. With four models, the experimental study on the oil leakage has been investigated for the oil temperature, intake pressure, and camshaft speed. The experimental results show that the sealing performance of the valve stem seal plays an important role on the leakage of the valve stem system. And the appropriate replacement of a stem seal with used poppet valve shows good sealing performance in oil leakage in compared with a new valve system.
Analysis of Lubrication and Dynamic Characteristics of a Cylinder Block for Hydraulic Pump
Journal of the Korean Society of Tribologists and Lubrication Engineers, volume 20, issue 4, 2004, Pages 209~217
Lubrication characteristics between a cylinder block and a valve plate for high speed bent-axis type hydraulic pump play an important role in volumetric efficiency and durability of pump. In this paper, a finite element method is presented for the computation of the pressure distribution between a cylinder block and a valve plate for high speed bent-axis type hydraulic pump. Also, a Runge-Kutta method is applied to simulate the cylinder block dynamics of three-degrees of freedom motion. From the results of computation, we can draw two major conclusions. One is related to the fluid film characteristics between a cylinder block and a valve plate and the other is related to the average leakage that is determined by the pressure gradient and the clearance near the discharge port. The numerical results of cylinder block dynamics were compared with the experimental results using eddy-current type gap sensors those are fixed at a pump housing.