An Investigation of the Steady-State Performance of a Wave Aerodynamic Thrust Bearing for High Speed Applications

2012 ◽  
Author(s):  
Nicoleta M. Ene ◽  
Florin Dimofte
Keyword(s):  
Steady State ◽  
High Speed ◽  
Thrust Bearing ◽  
Outer Diameter ◽  
Axial Loads ◽  
Numerical Predictions ◽  
Minimum Film Thickness ◽  
Computer Codes ◽  
Inner Diameter ◽  
Steady State Performance

The steady-state performance of an aerodynamic double thrust wave bearing was investigated. The investigation showed that a double thrust wave bearing with an inner diameter of 15 mm and an outer diameter of 45 mm can support axial loads of 200 N at 100,000 rpm for a minimum film thickness of 3 microns. The influence of the wave bearing parameters on the bearing performance was also analyzed. The theoretical analysis was validated by experimentally testing one side of the thrust bearing. A special test rig was built for this purpose. The experimental data were close to the numerical predictions, validating the computer codes.

Effect of the Field Shaper Geometries in Electromagnetic Crimping of Tubes on Rods

2019 ◽  
Vol 141 (11) ◽  
Author(s):  
Ramesh Kumar ◽  
Sachin D. Kore
Keyword(s):  
Experimental Study ◽  
High Speed ◽  
High Strain ◽  
Effective Length ◽  
Outer Diameter ◽  
Solenoid Coil ◽  
Element Analysis ◽  
Materials Properties ◽  
Inner Diameter ◽  
Joining Process

Abstract Electromagnetic crimping is a solid state, high-speed, and high strain-rate joining process. Finite element analysis, as well as experimental study, was carried out on three types of field shapers, namely, tapered, taper-stepped, and stepped. In all three field shapers, the effective length, outer diameter, inner diameter, total length, and materials properties were constant. These field shapers were kept inside the same multi-turn solenoid coil for all the experiments. It was found that the taper-stepped field shaper results better regarding impact velocity, Lorentz force, temperature generation, less heating, and uniformity in crimping among the three types of field shapers.

Static and Dynamic Performance of an Infinite Stiffness Hydrostatic Thrust Bearing

1977 ◽  
Vol 99 (1) ◽  
pp. 106-112 ◽  
Author(s):  
N. Tully
Keyword(s):  
Steady State ◽  
Vibration Analysis ◽  
Thrust Bearing ◽  
Dynamic Performance ◽  
Cone Angle ◽  
Vibration Absorber ◽  
Static Stiffness ◽  
Load Range ◽  
Normal Diaphragm ◽  
Steady State Performance

A novel form of variable hydrostatic restriction is proposed which will automatically achieve a high, infinite or negative static stiffness over a substantial load range. The restrictor is formed between the bearing body and a spring mounted conical plug. The steady state performance is analyzed and design curves presented which are valid for any cone angle from zero, i.e., fixed clearance, to 90 deg which is the normal diaphragm restrictor. The dynamic response to forced sinusoidal vibrations is examined in conventional vibration analysis form and it is found that the restrictor system may be designed to act as a vibration absorber.

Steady State Performance Characteristics of a Tilting Pad Thrust Bearing

2000 ◽  
Vol 123 (3) ◽  
pp. 608-615 ◽  
Author(s):  
Sergei B. Glavatskikh
Keyword(s):  
Steady State ◽  
Film Thickness ◽  
Thrust Bearing ◽  
Operating Conditions ◽  
Performance Characteristics ◽  
Shaft Speed ◽  
Oil Film ◽  
Tilting Pad ◽  
Bearing Load ◽  
Steady State Performance

The paper reports results of the experimental investigation into the steady state performance characteristics of a tilting pad thrust bearing typical of design in general use. Simultaneous measurements are taken of the pad and collar temperatures, the pressure distributions, oil film thickness, and power loss as a function of shaft speed, bearing load, and supplied oil temperature. The effect of operating conditions on bearing performance is discussed. A small radial temperature variation is observed in the collar. A reduction in minimum oil film thickness with load is approximately proportional to p−0.6, where p is an average bearing pressure. It has also been found that the oil film pressure profiles change not only due to the average bearing load but also with an increase in shaft speed and temperature of the supplied oil.

scholarly journals Steady-state performance investigation of open-circuit hydrostatic drives used in the rotary head of drill machine

2017 ◽  
Vol 233 (1) ◽  
pp. 3-20 ◽  
Author(s):  
Alok Vardhan ◽  
K Dasgupta ◽  
N Kumar ◽  
Santosh Kr Mishra
Keyword(s):  
Steady State ◽  
High Speed ◽  
Mining Operation ◽  
Open Circuit ◽  
Alternative Drive ◽  
Displacement Pump ◽  
Torque Loss ◽  
Drive Systems ◽  
Low Torque ◽  
Steady State Performance

This paper highlights the steady-state performance of open-circuit hydrostatic drives for the rotary head of drill machine through modeling and experiment. In this respect, two alternative drive systems are considered. A drive system that consists of a variable displacement pump and two high-speed low-torque hydro-motors with a gear reducer unit and the other one consists of an identical pump and a low-speed high-torque hydro-motor. The steady-state model of the proposed drive arrangements is made by bondgraph simulation technique, where the relationship of the various losses of the components are obtained as a function of operating parameters and are identified experimentally. Using them, the slip and torque loss along with the overall efficiency of the drives are characterized. The performances of the hydrostatic drives are compared for the usual operating speed range of the drill machine used in mining operation. The studies made also identify the operating range of the proposed hydrostatic drives with reasonable efficiency.

Analysis and comparison of steady-state performance characteristics of two-axial groove and multilobe hydrodynamic bearings lubricated with non-Newtonian fluids

2018 ◽  
Vol 232 (12) ◽  
pp. 1581-1596 ◽  
Author(s):  
Bhrigu Jyoti Das ◽  
Lintu Roy
Keyword(s):  
Steady State ◽  
High Speed ◽  
Journal Bearing ◽  
Maximum Flow ◽  
Maximum Load ◽  
Performance Characteristics ◽  
Flow Coefficient ◽  
Rotating Speed ◽  
The Stability ◽  
Steady State Performance

Rotating machines are one of the most important and widely used machineries in the modern engineering world. They are also the required to run at high rotating speed. The plain journal bearing is mostly replaced by some other bearing, as it does not suit the stability requirement of high-speed machines and precision machine tools. In order to improve the stability of a circular bearing, many researchers tried to change its geometrical configuration. In view of this, an attempt has been made in the present work to study the performance characteristics of four different bearing configurations using non-Newtonian lubricant and comparison of the results has been made with plain journal bearing. To calculate the steady-state performance characteristics, nondimensional form of the Reynolds equation using non-Newtonian lubricant has been written and solved for the steady-state nondimensional pressure distribution in a finite grid using finite difference method with successive over-relaxation technique satisfying appropriate boundary condition. From the study, it can be concluded that three-lobe bearing have maximum load-carrying capacity and minimum friction variable, whereas two-lobe bearing have maximum flow coefficient.

Study on the Dynamic Characteristics of the Large Diamond Circular Saw Blade

2014 ◽  
Vol 945-949 ◽  
pp. 781-784 ◽  
Author(s):  
Min Zhao ◽  
Lin Zhang ◽  
Bin Wu
Keyword(s):  
High Speed ◽  
Outer Diameter ◽  
Circular Saw ◽  
Experiment Method ◽  
Circular Saw Blade ◽  
Inner Diameter ◽  
Vibration Problems ◽  
Saw Blade ◽  
Vibration Modal ◽  
Large Diamond

Large diamond circular saw blade is a plane with large diameters and thin thick, so there are serious vibration problems in the process of sawing stone under the high-speed. By using the force hammer producing incentive experiment method, the effect of the inner and outer diameters to the vibration modal and frequency of diamond circular saw blade are analyzed. Through comparing inner and outer diameter, it can be found that the inner diameter has greater influence on the natural frequency, while the outer diameter has greater influence on the amplitude. The result supplies reliable data for eliminate or reduce resonance damage.

Experimental Measurement of CTOA During Ductile Crack Propagation in Pipeline Burst Tests

2018 ◽  
Author(s):  
Kazuki Shibanuma ◽  
Hikaru Yamaguchi ◽  
Takahiro Hosoe ◽  
Katsuyuki Suzuki ◽  
Shuji Aihara
Keyword(s):  
Steady State ◽  
Crack Propagation ◽  
Crack Velocity ◽  
High Speed ◽  
Crack Arrest ◽  
Opening Angle ◽  
Small Scale ◽  
Outer Diameter ◽  
Burst Test ◽  
Pipe Burst

Dynamic measurement of drop-weight tear test (DWTT) and pipe burst test for 356 mm outer diameter and 9.5 mm wall thickness steel pipe were conducted using high-speed camera. Crack velocity in the DWTT were 10 m/s during the steady state. Crack Tip Opening Angle (CTOA) values measured in the DWTT showed the constant value of about 20.1° during steady state propagation. On the other hand, crack velocity in the burst test showed monotonically decreasing during crack propagation from 200 m/s but it was found that CTOA value kept constant value of about 13.2° until crack arrest irrespective of the crack velocity. These results showed the validation of the CTOA criterion for the high-pressure gas pipelines. The results also showed that CTOA in a burst test is generally different from that in a test using small-scale specimen. Future developments of the experimental procedure using a small-scale specimen to provide CTOA value corresponding with that in a burst test would be effective.

Analysis of High-Speed Energy-Storing Flywheel Rotor

2012 ◽  
Vol 214 ◽  
pp. 249-253
Author(s):  
Xiu Hua Zhang ◽  
Xue Feng Zhao ◽  
Xing Lei Zhang
Keyword(s):  
High Speed ◽  
Maximum Energy ◽  
Structure Design ◽  
Outer Diameter ◽  
Analysis Method ◽  
Interference Fit ◽  
Analysis And Design ◽  
Finite Element Software ◽  
Inner Diameter ◽  
Flywheel Rotor

Appropriate rotor material and reasonable structure should be used for increase energy-storing density of flywheel. Theoretical analysis and design to high-speed energy-storing flywheel rotor with maximum energy-storing density is studied in the paper．The ratio of inner diameter and outer diameter and structure dimensions of a given condition flywheel rim is obtained by calculating. And the interference fit of rim/hub of the flywheel is analyzed with finite element software. One efficient and reliable calculating foundation and analysis method for the structure design of the flywheel rotor is provided.

Sign in / Sign up

Export Citation Format

Share Document