Longitudinal Impact of Cylindrical Shells With Discontinuous Cross-Sectional Area

1972 ◽  
Vol 39 (4) ◽  
pp. 1005-1010 ◽  
Author(s):  
R. W. Mortimer ◽  
J. L. Rose ◽  
A. Blum
Keyword(s):  
Cylindrical Shells ◽  
Cross Sectional Area ◽  
Experimental Results ◽  
Longitudinal Impact ◽  
Sectional Area ◽  
Governing Equations ◽  
Cross Sectional ◽  
Inertia Effects ◽  
Stress Ratios ◽  
Good Agreement

The reflections and transmissions of longitudinal strain pulses in cylindrical shells having cross-sectional area discontinuities are studied both analytically and experimentally. Three different theories were used to analyze this problem: the first, termed “bending” theory, includes the transverse shear, radial inertia, and rotary inertia effects; the second is based on a modified “membrane” theory; the last is derived from the “uniaxial” theory. Solutions were obtained by solving each of the three systems of governing equations by the method of characteristics. The longitudinal and circumferential incident, reflected, and transmitted strain pulses calculated from the bending and membrane theories are shown to be in good agreement with the experimental results, whereas the uniaxial comparisons are poor. In addition, the calculated reflected and transmitted stress ratios are in good agreement with the experimental results; the ratios obtained from the uniaxial theory are shown to be generally inadequate.

Variable Inertia Damper Using MR Fluid

2016 ◽  
Author(s):  
Taichi Matsuoka ◽  
Kazuhiko Hiramoto ◽  
Katsuaki Sunakoda ◽  
Naoto Abe
Keyword(s):  
Dynamic Property ◽  
Cross Sectional Area ◽  
Experimental Results ◽  
Moving Mass ◽  
Inertia Effect ◽  
Sectional Area ◽  
Cross Sectional ◽  
Mr Fluid ◽  
Damping Effect ◽  
New Type

Inertia damper has an inertia effect by a flywheel which is caused by a quick moving mass. In general, it is difficult to change the inertia mass physically. In order to obtain a variable inertia effect, a new type of inertia damper has a long bypass pipe is proposed in this paper. This type of damper generates a damping effect and inertia effect by the fluid. It is noted that the inertia effect is depended on a density of the fluid, cross sectional areas of cylinder and bypass pipe, and length of the bypass pipe. If the diameter of the bypass pipe can be controlled, it means that a cross sectional area of the bypass pipe can be switched by clustering particles of MR fluid under magnetization, the inertia effect might be artificially controllable. A trial damper with several electromagnets installed along the long bypass pipe is manufactured, and dynamic property is measured when MR fluid inside the bypass pipe is magnetized by the electromagnets. From experimental results, it seems to be that the inertia effect can be switched and depended on amplitude of magnetization. Finally, the calculated results are theoretically approached, and compared with the experimental results.

Relationships Between Cutting Force Variations and Cutting Factors in Plain Milling Operations. Part 1: Plain Milling With a Single-Toothed Helical Cutter

1981 ◽  
Vol 103 (2) ◽  
pp. 165-173
Author(s):  
S. Kato ◽  
T. Yamada ◽  
M. Hashimoto ◽  
K. Yamaguchi
Keyword(s):  
Cutting Force ◽  
Optical Method ◽  
Constant Width ◽  
Cross Sectional Area ◽  
Experimental Results ◽  
Sectional Area ◽  
Cross Sectional ◽  
Milling Operations ◽  
Variation Patterns ◽  
Force Variation

In plain milling operations with a single-toothed helical cutter, three components of cutting force are measured simultaneously and continuously corresponding to the varying cross-sectional area of cut by means of a unique optical method. Based on the measured cutting force variation in a constant width of cut, some required cutting force variations in various widths of cut can be obtained by summing up the overlapped basic cutting force variation patterns. Relationships between cutting force variations and cutting factors in plain milling operations are explained on the basis of the experimental results and the expanded results of experiments.

scholarly journals Longitudinal dispersion in natural channels: l. Experimental results from the River Severn, U.K.

2000 ◽  
Vol 4 (3) ◽  
pp. 345-353 ◽  
Author(s):  
T. C. Atkinson ◽  
P. M. Davis
Keyword(s):  
Line Source ◽  
Short Interval ◽  
Tracer Experiment ◽  
Cross Sectional Area ◽  
Experimental Results ◽  
Longitudinal Dispersion ◽  
Sectional Area ◽  
Cross Sectional ◽  
Channel Geometry ◽  
Rhodamine Wt

Abstract. Abstract: A tracer experiment using Rhodamine WT dye was carried out to measure longitudinal dispersion in a 14-km reach of the River Severn in Wales, U.K. The river’s discharge was measured at six points and the depth, width and cross-sectional area were measured at 86 points along the test reach. The channel geometry was close to being statistically uniform. Discharge and velocity were both nearly constant. Dye concentrations were recorded at stations between 210 and 13775 m downstream of injection. Dye was injected over a short interval as a near-uniform line source across the channel. These conditions make the data useful for testing mathematical theories of dispersion. They are presented in full. Keywords: Channels; dispersion; tracers; River Severn

Determination of Allowable Pushrod Angle Using a Three-Dimensional Valve Train Model

1998 ◽  
Vol 123 (3) ◽  
pp. 408-412 ◽  
Author(s):  
C. Y. Cheng ◽  
D. J. Lewandowski ◽  
J. W. David
Keyword(s):  
Dynamic Performance ◽  
Three Dimensional ◽  
Cross Sectional Area ◽  
Experimental Results ◽  
Valve Train ◽  
Intake Port ◽  
Sectional Area ◽  
Cross Sectional ◽  
Engine Power

Pushrod-type valve trains are still found in many engines. Since a vertical pushrod causes interference with the intake port, which reduces engine power, the pushrod is sometimes tilted to increase the available cross-sectional area of the intake port. In order to analyze this mechanism, a three-dimensional valve train model was developed. The model is then verified through experimention. Simulation and experimental results agree that valve train dynamic performance is not significantly affected by pushrod angles less than 20 degrees.

Pelvic Canal Narrowing Caused by Triple Pelvic Osteotomy in the Dog

1994 ◽  
Vol 07 (03) ◽  
pp. 110-113 ◽  
Author(s):  
D. L. Holmberg ◽  
M. B. Hurtig ◽  
H. R. Sukhiani
Keyword(s):  
Postoperative Complications ◽  
Pelvic Osteotomy ◽  
Cross Sectional Area ◽  
Sectional Area ◽  
Cross Sectional ◽  
Canal Width ◽  
Operative Complications ◽  
Post Operative Complications

SummaryDuring a triple pelvic osteotomy, rotation of the free acetabular segment causes the pubic remnant on the acetabulum to rotate into the pelvic canal. The resulting narrowing may cause complications by impingement on the organs within the pelvic canal. Triple pelvic osteotomies were performed on ten cadaver pelves with pubic remnants equal to 0, 25, and 50% of the hemi-pubic length and angles of acetabular rotation of 20, 30, and 40 degrees. All combinations of pubic remnant lengths and angles of acetabular rotation caused a significant reduction in pelvic canal-width and cross-sectional area, when compared to the inact pelvis. Zero, 25, and 50% pubic remnants result in 15, 35, and 50% reductions in pelvic canal width respectively. Overrotation of the acetabulum should be avoided and the pubic remnant on the acetabular segment should be minimized to reduce postoperative complications due to pelvic canal narrowing.When performing triple pelvic osteotomies, the length of the pubic remnant on the acetabular segment and the angle of acetabular rotation both significantly narrow the pelvic canal. To reduce post-operative complications, due to narrowing of the pelvic canal, overrotation of the acetabulum should be avoided and the length of the pubic remnant should be minimized.

DETERMINATION OF THE FUNCTION OF THE ROD’S CROSS-SECTIONAL AREA USING VIBRATION EIGENFREQUENCIES

2020 ◽  
Vol 0 (4) ◽  
pp. 19-24
Author(s):  
I.M. UTYASHEV ◽  
◽  
A.A. AITBAEVA ◽  
A.A. YULMUKHAMETOV ◽  
◽  
...  
Keyword(s):  
Cross Sectional Area ◽  
Variable Cross ◽  
Sectional Area ◽  
Longitudinal Vibrations ◽  
Cross Sectional ◽  
Method Error ◽  
Various Boundary Conditions ◽  
Elastic Fixation ◽  
Crosssectional Area

The paper presents solutions to the direct and inverse problems on longitudinal vibrations of a rod with a variable cross-sectional area. The law of variation of the cross-sectional area is modeled as an exponential function of a polynomial of degree n . The method for reconstructing this function is based on representing the fundamental system of solutions of the direct problem in the form of a Maclaurin series in the variables x and λ. Examples of solutions for various section functions and various boundary conditions are given. It is shown that to recover n unknown coefficients of a polynomial, n eigenvalues are required, and the solution is dual. An unambiguous solution was obtained only for the case of elastic fixation at one of the rod’s ends. The numerical estimation of the method error was made using input data noise. It is shown that the error in finding the variable crosssectional area is less than 1% with the error in the eigenvalues of longitudinal vibrations not exceeding 0.0001.

Changes in the parameters of nasal breathing and parameters of the upper respiratory tract during orthognathic operations in patients with II and III skeletal class of jaw anomalies

2020 ◽  
pp. 22-27
Author(s):  
S.Sh. Gammadaeva ◽  
M.I. Misirkhanova ◽  
A.Yu. Drobyshev
Keyword(s):  
Respiratory Tract ◽  
Nasal Cavity ◽  
Nasal Septum ◽  
Cross Sectional Area ◽  
Upper Respiratory Tract ◽  
Sectional Area ◽  
Nasal Breathing ◽  
Cross Sectional ◽  
Skeletal Class ◽  
Upper Respiratory

The study analyzed the functional parameters of nasal breathing, linear parameters of the nasal aperture, nasal cavity and nasopharynx, volumetric parameters of the upper airways in patients with II and III skeletal class of jaw anomalies before and after orthognathic surgery. The respiratory function of the nose was assessed using a rhinomanometric complex. According to rhinoresistometry data, nasal resistance and hydraulic diameter were assessed. According to the data of acoustic rhinometry, the minimum cross-sectional area along the internal valve, the minimum cross-sectional area on the head of the inferior turbinate and nasal septum and related parameters were estimated. According to the CBCT data, the state of the nasal septum, the inferior turbinates, the nasal aperture, the state of the nasal cavity, and the linear values of the upper respiratory tract (nasopharynx) were analyzed. The patients were divided into 4 groups according to the classification of the patency of the nasal passages by

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