Study on Nanofiber Spinning Using Centrifugal Force - Rotational Speed of Spinning Disk vs Nanofiber/Microfiber Diameter when Disk Speed is Increased via Gears -

Considering the effect of centrifugal force generated by the rotation to the crankshaft frequency and vibration mode, the frequency and vibration mode of multi-speed cases are calculated. The results showed that the impact of the centrifugal force on the crankshaft vibration increases with the increase of rotational speed, especially in the high speed region, this phenomenon is more obvious. From low speed to high speed, the vibration frequency has a large deviation, which shows that in this case, it is necessary to consider the frequency change caused by pre-stress.

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I. On the magnetic rotation of the plane of polarisation of light in doubly refracting bodies

Proceedings of the Royal Society of London ◽

10.1098/rspl.1889.0007 ◽

1890 ◽

Vol 46 (280-285) ◽

pp. 65-71

Keyword(s):

Magnetic Field ◽

Centrifugal Force ◽

Magnetic Rotation ◽

Spinning Disk ◽

Axis Of Rotation ◽

Elliptic Polarisation ◽

Incident Plane ◽

Polarised Light ◽

The Magnetic Field ◽

Lines Of Force

In repeating Villari’s experiment on the rotation of the plane of polarisation of light in a spinning disk of heavy glass, placed with its axis of rotation perpendicular to the lines of force in a magnetic field, it was observed that the incident plane polarised light became elliptically polarised. The elliptic polarisation was due to the centrifugal force which had the effect of stretching the glass along the radii of the disk and compressing it parallel to the axis of rotation. The strained glass in the magnetic field has, therefore, the double property of elliptically polarising plane polarised light, and at the same time rotating the plane of polarisation.

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In-Plane Stress and Displacement Distributions in a Spinning Annular Disk Under Stationary Edge Loads

Journal of Applied Mechanics ◽

10.1115/1.2788997 ◽

1997 ◽

Vol 64 (4) ◽

pp. 897-904 ◽

Cited By ~ 6

Author(s):

Jen-San Chen ◽

Jhi-Lu Jhu

Keyword(s):

Plane Stress ◽

Rotational Speed ◽

Stress Function ◽

Classical Solutions ◽

Airy Stress Function ◽

Displacement Fields ◽

Centrifugal Effect ◽

Annular Disk ◽

Spinning Disk ◽

Stress And Displacement Fields

It is well known that the in-plane stress and displacement distributions in a stationary annular disk under stationary edge tractions can be obtained through the use of Airy stress function in the classical theory of linear elasticity. By using Lame’s potentials, this paper extends these solutions to the case of a spinning disk under stationary edge tractions. It is also demonstrated that the problem of stationary disk-spinning load differs from the problem of spinning disk-stationary load not only by the centrifugal effect, but also by additional terms arising from the Coriolis effect. Numerical simulations show that the amplitudes of the stress and displacement fields grow unboundedly as the rotational speed of the disk approaches the critical speeds. As the rotational speed approaches zero, on the other hand, the in-plane stresses and displacements are shown, both numerically and analytically, to recover the classical solutions derived through the Airy stress function.

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A Method for Measuring Pressure under Rotating Conditions

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.663.522 ◽

2013 ◽

Vol 663 ◽

pp. 522-527

Author(s):

Deng Chao Li ◽

Xiang Luo ◽

Xu Cai

Keyword(s):

Experimental Data ◽

Centrifugal Force ◽

Surface Pressure ◽

Pressure Sensor ◽

Rotational Speed ◽

Output Signal ◽

Functional Relationship ◽

Sensor Output ◽

Strain Type ◽

Type Pressure

A method which can accurately measure surface pressure under rotating conditions is presented. Based on the calibration for strain type pressure sensor, a curve which shows the functional relationship between sensor output signal and actual pressure under different rotational speed is obtained; and the diaphragm deformation caused by centrifugal force can be neglected by the curve. Thus, the actual pressure can be acquired accurately. The factors which may cause errors on the experiment are analyzed. Moreover, the correctional method for the experimental data is attained.

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Effects of Load Parameters on the Natural Frequencies and Stability of a Flexible Spinning Disk With a Stationary Load System

Journal of Applied Mechanics ◽

10.1115/1.2899494 ◽

1992 ◽

Vol 59 (2S) ◽

pp. S230-S235 ◽

Cited By ~ 49

Author(s):

Jen-San Chen ◽

D. B. Bogy

Keyword(s):

Friction Force ◽

Centrifugal Force ◽

Natural Frequencies ◽

Numerical Solutions ◽

Positive Definite ◽

Transverse Mass ◽

Gyroscopic System ◽

Theoretical Understanding ◽

Spinning Disk ◽

Derivatives Of

The orthogonality properties among the eigenfunctions for a gyroscopic system are derived for a stiffness operator that is not positive definite. The derivatives of the eigenvalues with respect to certain parameters in the system are then obtained. The results are applied to a spinning disk in contact with a stationary load system, which contains such parameters as friction force, transverse mass, damping, stiffness, and the analogous pitching elements, to predict the effects of these parameters and the stiffening of the disk due to the centrifugal force on the natural frequencies and stability of the spinning disk. The results obtained provide a theoretical understanding for previously reported observations based on numerical solutions.

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Mist Generation During Metal Machining

Journal of Tribology ◽

10.1115/1.555399 ◽

2000 ◽

Vol 122 (3) ◽

pp. 544-549 ◽

Cited By ~ 18

Author(s):

Jonathan Thornburg ◽

David Leith

Keyword(s):

Fluid Flow ◽

Health Effects ◽

Centrifugal Force ◽

Rotational Speed ◽

Metalworking Fluids ◽

Adverse Health Effects ◽

Adverse Health ◽

Metal Machining ◽

Cut Depth

Use of metalworking fluids during machining results in a mist that is associated with adverse health effects. Experiments conducted on a small lathe quantified the amount of mist generated by evaporation/condensation, centrifugal force, and impaction. Evaporation/condensation was the most important mechanism, followed by centrifugal force, then impaction. For evaporation/condensation, rotational speed and cut depth determined the amount of heat generated during machining, whereas fluid flow determined the amount of heat transferred to the liquid. The flow-rotational speed interaction influenced mist generation by centrifugal force, whereas mist generation by impaction was determined only by fluid flow. [S0742-4787(00)01303-5]

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A review on nanofiber fabrication with the effect of high-speed centrifugal force field

Journal of Engineered Fibers and Fabrics ◽

10.1177/1558925019867517 ◽

2019 ◽

Vol 14 ◽

pp. 155892501986751 ◽

Cited By ~ 2

Author(s):

Zhi-Ming Zhang ◽

Yao-Shuai Duan ◽

Qiao Xu ◽

Biao Zhang

Keyword(s):

Surface Tension ◽

Force Field ◽

Centrifugal Force ◽

Formation Process ◽

Rotational Speed ◽

High Speed ◽

Solution Concentration ◽

Solution Viscosity ◽

Centrifugal Spinning ◽

Solution Parameters

Among the traditional methods for nanofiber fabrication, their inherent defects limit their application in industry. This work presents a simple and novel spinning technology to fabricate nanofiber, which uses a high-speed rotary spinneret called high-speed centrifugal spinning. Unlike electrospinning, the electric field is not required, and it could fabricate nanofiber in bulk from melt or solution materials. This work introduces the mechanism principle and development of high-speed centrifugal spinning. Besides, the high-speed centrifugal spinning is compared with the traditional spinning methods. The jet movement and nanofiber formation process under the action of centrifugal force are explained in detail. The effects of equipment parameters and spinning solution parameters on final nanofiber morphology are presented. These parameters are controllable, they include rotational speed of spinneret, length and diameter of nozzle, spinning solution concentration, spinning solution viscosity and surface tension, and collection distance.

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Balancing of Tool/Toolholder Assembly for High-Speed Machining

Materials Science Forum ◽

10.4028/www.scientific.net/msf.471-472.542 ◽

2004 ◽

Vol 471-472 ◽

pp. 542-546

Author(s):

Song Zhang ◽

Xing Ai ◽

Wei Xiao Tang ◽

J.G. Liu

Keyword(s):

Centrifugal Force ◽

Rotational Speed ◽

High Speed ◽

Manufacturing Industry ◽

High Speed Machining ◽

High Rotational Speed ◽

Good Balance ◽

Machining Quality ◽

System Maintenance

High-speed machining has become mainstream in machining manufacturing industry. In industries such as moldmaking and aerospace, it has become the norm rather the exception. The centrifugal force increases as the square of the speed. At rotational spindle speeds of 6,000 r/min and higher however, centrifugal force from unbalance becomes a damaging factor and it reduces the life of the spindle and the tool, as well as diminishes the quality of the finished product. Under high rotational speed, good balance becomes issue. High-speed machining experimental results shown that a well-balanced tool/toolholder assembly could obviously improve machining quality, extend tool life and shorten downtime for spindle system maintenance etc.

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Numerical Analysis of The Effect of Hydrodynamics and Operating Conditions on Biodiesel Synthesis in a Rotor-Stator Spinning Disk Reactor

Chemical and Process Engineering ◽

10.1515/cpe-2017-0020 ◽

2017 ◽

Vol 38 (2) ◽

pp. 265-281 ◽

Cited By ~ 2

Author(s):

Zhuqing Wen ◽

Jerzy Petera

Keyword(s):

Rotational Speed ◽

Transport Model ◽

Rotating Disk ◽

Operating Conditions ◽

Diffusion Reaction ◽

Rotating Shaft ◽

Multicomponent Transport ◽

Spinning Disk ◽

Biodiesel Synthesis ◽

Lower Disk

AbstractA rotor-stator spinning disk reactor for intensified biodiesel synthesis is described and numerically simulated in the present research. The reactor consists of two flat disks, located coaxially and parallel to each other with a gap ranging from 0.1 mm to 0.2 mm between the disks. The upper disk is located on a rotating shaft while the lower disk is stationary. The feed liquids, triglycerides (TG) and methanol are injected into the reactor from centres of rotating disk and stationary disk, respectively. Fluid hydrodynamics in the reactor for synthesis of biodiesel from TG and methanol in the presence of a sodium hydroxide catalyst are simulated, using convection-diffusion-reaction multicomponent transport model with the CFD software ANSYS©Fluent v. 13.0. Effect of operating conditions on TG conversion is particularly investigated. Simulation results indicate that there is occurrence of back flow close to the stator at the outlet zone. Small gap size and fast rotational speed generally help to intensify mixing among reagents, and consequently enhance TG conversion. However, increasing rotational speed of spinning disk leads to more backflow, which decreases TG conversion. Large flow rate of TG at inlet is not recommended as well because of the short mean residence time of reactants inside the reactor.

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