Minimizing the Negative Effects of Coolant Channels on the Torsional and Torsional-Axial Stiffness of Drills

Coolant channels allow internal coolant delivery to the cutting region and significantly improve drilling, but these channels also reduce the torsional and torsional-axial stiffness of the drills. Such a reduction in stiffness can degrade the quality of the drilled holes. The evacuation of cutting chips and the delivery of the cutting fluid put strict geometrical restrictions on the cross-section design of the drill. This necessitates careful selection and optimization of features such as the geometry of the coolant channels. This paper presents a new method that uses Prandtl’s stress function to predict the torsional and torsional-axial stiffness values. Using this method drills with one central channel are compared to those with two eccentric coolant channels, which shows that with the same cross-section area, the reduction of axial and torsional-axial stiffness is notably smaller for the design with two eccentric channels compared to a single central channel. The stress function method is further used to select the appropriate location of the eccentric coolant channels to minimize the loss of torsional and torsional-axial stiffness. These results are verified by comparison to the results of three-dimensional finite element analyses.

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Determination of physiological cross-section area of patient-specific masticatory muscles with three-dimensional medical imaging analysis

Proceedings of the Second Joint 24th Annual Conference and the Annual Fall Meeting of the Biomedical Engineering Society] [Engineering in Medicine and Biology ◽

10.1109/iembs.2002.1053415 ◽

2003 ◽

Author(s):

Linping Zhao ◽

P.K. Patel ◽

G.E.O. Widera ◽

G.F. Harris

Keyword(s):

Medical Imaging ◽

Cross Section ◽

Three Dimensional ◽

Masticatory Muscles ◽

Patient Specific ◽

Imaging Analysis ◽

Cross Section Area ◽

Section Area

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Size effects on compressive behaviors of three-dimensional braided composites under high strain rates

Journal of Composite Materials ◽

10.1177/0021998318771459 ◽

2018 ◽

Vol 52 (28) ◽

pp. 3895-3908 ◽

Cited By ~ 4

Author(s):

Tao Liu ◽

Baozhong Sun ◽

Bohong Gu

Keyword(s):

Cross Section ◽

Three Dimensional ◽

Sample Length ◽

Braided Composites ◽

Element Analysis ◽

Cross Section Area ◽

Section Area ◽

Unit Cells ◽

Microstructure Model ◽

The Cross

The compressive behaviors of three-dimensional braided composites with different cross sections and lengths along braided direction under high strain rates were reported from numerical simulations and experimental tests. The microstructure models with and without defects were established. The microstructure model with random distributed defects was to investigate the influence of sample length and random defects on the compressive properties. The microstructure model without defects is to reveal the effect of the cross section area on the compressive behavior. We found from finite element analysis that volume fractions of interior, surface, and corner unit cells vary with the cross section area. The strength and modulus were sensitive to the volume fractions of the unit cells and defects in the braided composites. The effect of the sample length on the compressive behaviors was not as significant as the cross section area and defects. The testing validated the finite element analysis results well.

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Colour Doppler Sonographic Estimation of Vascular Stenosis by Peak Systolic Velocity, Vessel Diameter and Vessel Cross Section Area With and Without Levovist

European Journal of Ultrasound ◽

10.1016/s0929-8266(97)87253-9 ◽

1997 ◽

Vol 6 ◽

pp. S28-S29

Author(s):

K Kroger

Keyword(s):

Cross Section ◽

Peak Systolic Velocity ◽

Vessel Diameter ◽

Colour Doppler ◽

Cross Section Area ◽

Section Area ◽

Vascular Stenosis

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SAF file: It's really three dimensional file

Mustansiria Dental Journal ◽

10.32828/mdj.v14i1.744 ◽

2018 ◽

Vol 14 (1) ◽

pp. 1

Author(s):

Prof. Dr. Jamal Aziz Mehdi

Keyword(s):

Cross Section ◽

Root Canal ◽

Three Dimensional ◽

Circular Cross Section ◽

Circular Motion ◽

Root Canal Treatment ◽

Metal Core ◽

Rotating Blade

The biological objectives of root canal treatment have not changed over the recentdecades, but the methods to attain these goals have been greatly modified. Theintroduction of NiTi rotary files represents a major leap in the development ofendodontic instruments, with a wide variety of sophisticated instruments presentlyavailable (1, 2).Whatever their modification or improvement, all of these instruments have onething in common: they consist of a metal core with some type of rotating blade thatmachines the canal with a circular motion using flutes to carry the dentin chips anddebris coronally. Consequently, all rotary NiTi files will machine the root canal to acylindrical bore with a circular cross-section if the clinician applies them in a strictboring manner

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ANALYSIS OF THE GENERAL EQUATIONS OF THE TRANSVERSE VIBRATION OF A PIECEWISE UNIFORM VISCOELASTIC PLATE

Computational nanotechnology ◽

10.33693/2313-223x-2020-7-3-52-56 ◽

2020 ◽

Vol 7 (3) ◽

pp. 52-56

Author(s):

MMATMATISA JALILOV ◽

◽

RUSTAM RAKHIMOV ◽

Keyword(s):

Cross Section ◽

Transverse Vibration ◽

Three Dimensional ◽

Viscoelastic Plate ◽

Constant Thickness ◽

Regional Problem ◽

Rigid Contact ◽

Under Construction ◽

Derivatives Of ◽

Theoretical Results

This article discusses the analysis of the general equations of the transverse vibration of a piecewise homogeneous viscoelastic plate obtained in the “Oscillation of inlayer plates of constant thickness” [1]. In the present work on the basis of a mathematical method, the approached theory of fluctuation of the two-layer plates, based on plate consideration as three dimensional body, on exact statement of a three dimensional mathematical regional problem of fluctuation is stood at the external efforts causing cross-section fluctuations. The general equations of fluctuations of piecewise homogeneous viscoelastic plates of the constant thickness, described in work [1], are difficult on structure and contain derivatives of any order on coordinates x, y and time t and consequently are not suitable for the decision of applied problems and carrying out of engineering calculations. For the decision of applied problems instead of the general equations it is expedient to use confidants who include this or that final order on derivatives. The classical equations of cross-section fluctuation of a plate contain derivatives not above 4th order, and for piecewise homogeneous or two-layer plates the elementary approached equation of fluctuation is the equation of the sixth order. On the basis of the analytical decision of a problem the general and approached decisions of a problem are under construction, are deduced the equation of fluctuation of piecewise homogeneous two-layer plates taking into account rigid contact on border between layers, and also taking into account mechanical and rheological properties of a material of a plate. The received theoretical results for the decision of dynamic problems of cross-section fluctuation of piecewise homogeneous two-layer plates of a constant thickness taking into account viscous properties of their material allow to count more precisely the is intense-deformed status of plates at non-stationary external loadings.

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Analysis of the difference between the area of the cross section area and the surface EMG and the Maximum muscle strength according to the presence of the patellofemoral pain syndrome

Korean Journal of Sports Science ◽

10.35159/kjss.2020.02.29.1.803 ◽

2020 ◽

Vol 29 (1) ◽

pp. 803-811

Author(s):

Wan-Ki Hong ◽

Cheol-Hee Park

Keyword(s):

Muscle Strength ◽

Cross Section ◽

Pain Syndrome ◽

Patellofemoral Pain Syndrome ◽

Surface Emg ◽

Patellofemoral Pain ◽

Cross Section Area ◽

Section Area ◽

The Cross ◽

The Difference

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Boundary element method in numerical study of three-dimensional Stokes flows in channels of arbitrary shape

Proceedings of the Mavlyutov Institute of Mechanics ◽

10.21662/uim2012.1.018 ◽

2012 ◽

Vol 9 (1) ◽

pp. 94-97

Author(s):

Yu.A. Itkulova

Keyword(s):

Boundary Element Method ◽

Boundary Element ◽

Cross Section ◽

Numerical Study ◽

Three Dimensional ◽

Cylindrical Tube ◽

Variable Cross Section ◽

Variable Cross ◽

Periodic Flows ◽

Element Method

In the present work creeping three-dimensional flows of a viscous liquid in a cylindrical tube and a channel of variable cross-section are studied. A qualitative triangulation of the surface of a cylindrical tube, a smoothed and experimental channel of a variable cross section is constructed. The problem is solved numerically using boundary element method in several modifications for a periodic and non-periodic flows. The obtained numerical results are compared with the analytical solution for the Poiseuille flow.

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