Systematic design of cantilever beams for muscle research

1977 ◽  
Vol 42 (5) ◽  
pp. 786-794 ◽  
Author(s):  
R. J. McLaughlin
Keyword(s):  
Elastic Modulus ◽  
Cross Section ◽  
Experimental Studies ◽  
Circular Cross Section ◽  
Design Procedure ◽  
Structural Materials ◽  
Thick Wall ◽  
Beam Parameter ◽  
Thin Wall ◽  
Cantilever Beams

Experimental studies of muscle contraction often involve difficult problems in the design of cantilever beams for movable levers, transducers, or mechanical supports. Equations are presented for the calculation of mass, inertia, stress distribution, strain, deflection curve, compliance, and resonant frequency of uniform or nonuniform cantilever beams made of structural materials of different density or elastic modulus. Formulas are listed for solid, thick-wall, and thin-wall uniform beams of rectangular and circular cross section. Physical properties including density, elastic and torsional moduli, stress and strain limits, thermal expansion coefficients, Poisson's ratio, and certain elastic-modulus-to-density ratios are tabulated for structural materials including common metals, glass, plastic, and wood. A graphical design procedure is presented based on a chart containing loci of constant beam parameter values as a function of beam length and height or diameter, for the simple geometries. The choice of structural material is discussed for design problems with typical constraints, and examples are given of the design of beams of nonuniform cross section. Methods for extending the design chart to other geometries and materials are included.

Bending Vibrations of Variable Section Beams

1956 ◽  
Vol 23 (1) ◽  
pp. 103-108
Author(s):  
E. T. Cranch ◽  
Alfred A. Adler
Keyword(s):  
Cross Section ◽  
Rectangular Cross Section ◽  
Circular Cross Section ◽  
Beam Theory ◽  
Cantilever Beams ◽  
Constant Depth ◽  
Bending Vibrations ◽  
Variable Section

Abstract Using simple beam theory, solutions are given for the vibration of beams having rectangular cross section with (a) linear depth and any power width variation, (b) quadratic depth and any power width variation, (c) cubic depth and any power width variation, and (d) constant depth and exponential width variation. Beams of elliptical and circular cross section are also investigated. Several cases of cantilever beams are given in detail. The vibration of compound beams is investigated. Several cases of free double wedges with various width variations are discussed.

scholarly journals From 0D to 3D Aero-Thermo-Fluid Simulations of a Fan Outlet Guide Vane Cooler (FOGVC)

2021 ◽  
Author(s):  
Luis Costero Sánchez ◽  
Klaus Höschler ◽  
Sagar Sadananda Bhat
Keyword(s):  
Cross Section ◽  
Guide Vane ◽  
Rectangular Cross Section ◽  
Circular Cross Section ◽  
Heat Rate ◽  
Internal Cavity ◽  
Thin Wall ◽  
Wall Model ◽  
Ansys Fluent ◽  
First Time

As the first time, 0D-1D-3D and fully 3D steady-state aero-thermo-fluid simulations of a structural oil-to-air Fan Outlet Guide Vane Cooler (FOGVC) in a jet engine are presented. Using the commercial softwares Ansys Fluent, the thermo-mechanical module of Ansys and the 1D fluid solver Flownex, 5 simulation types (3D fully conjugate heat transfer with and without a thin wall model, 3D with a thin wall model, 1D-3D coupled, 1D and 0D) corresponding to 4 levels of simplification in 3 possible domains (oil, oil-metal and oil-metal-air) have been compared to provide selection criteria when a determined level of accuracy in the simulations without prohibited computational times is desired. The methodologies are applied to two different oil internal cavities: an inverted U with rectangular cross section and a coil internal cavity with a circular cross section. The obtained results show that depending on the scope of the research (outlet oil temperature, dissipated heat rate or oil pressure drop) and the accuracy of the results, one method or the other may be used. Experimental data would be needed to validate the numerical results by all employed methodologies and geometries.

Design and Numerical Simulation of Radial Inflow Turbine Volute

2014 ◽  
Vol 31 (4) ◽  
Author(s):  
Samip P. Shah ◽  
S.A. Channiwala ◽  
D.B. Kulshreshtha ◽  
Gaurang Chaudhari
Keyword(s):  
Compressible Flow ◽  
Cross Section ◽  
Cross Sections ◽  
Numerical Models ◽  
Circular Cross Section ◽  
Design Procedure ◽  
Design Parameters ◽  
Flow Angle ◽  
Trapezoidal Cross Section ◽  
Radial Inflow Turbine

AbstractThe volute of a radial inflow turbine has to be designed to ensure that the desired rotor inlet conditions like absolute Mach number, flow angle etc. are attained. For the reasonable performance of vaneless volute turbine care has to be taken for reduction in losses at an appropriate flow angle at the rotor inlet, in the direction of volute, whose function is to convert gas energy into kinetic energy and direct the flow towards the rotor inlet at an appropriate flow angle with reduced losses. In literature it was found that the incompressible approaches failed to provide free vortex and uniform flow at rotor inlet for compressible flow regimes. So, this paper describes a non-dimensional design procedure for a vaneless turbine volute for compressible flow regime and investigates design parameters, such as the distribution of area ratio and radius ratio as a function of azimuth angle. The nondimensional design is converted in dimensional form for three different volute cross sections. A commercial computational fluid dynamics code is used to develop numerical models of three different volute cross sections. From the numerical models, losses generation in the different volutes are identified and compared. The maximum pressure loss coefficient for Trapezoidal cross section is 0.1075, for Bezier-trapezoidal cross section is 0.0677 and for circular cross section is 0.0438 near tongue region, which suggested that the circular cross section will give a better efficiency than other types of volute cross sections.

Energy Transfer From High-to Low-Frequency Modes in a Flexible Structure via Modulation

1994 ◽  
Vol 116 (2) ◽  
pp. 203-207 ◽  
Author(s):  
S. A. Nayfeh ◽  
A. H. Nayfeh
Keyword(s):  
Cross Section ◽  
High Frequency ◽  
Natural Frequencies ◽  
Circular Cross Section ◽  
Low Frequency ◽  
Cantilever Beams ◽  
Axially Symmetric ◽  
Internal Resonances ◽  
Planar Motions ◽  
High Frequency Modes

An experimental study of the response of axially-symmetric (i.e., circular cross-section) cantilever beams to planar external excitations is presented. Because of the axial symmetry, one-to-one internal resonances occur at each natural frequency. These resonances cause the planar motions to lose stability and nonplanar (whirling) motions are observed. Under certain conditions, periodically-and chaotically-modulated motions may occur. In addition, when the beam is excited near one of its high natural frequencies, large first-mode responses accompanied by slow modulations of the amplitudes and phases of high-frequency modes are observed. This interaction between high-and low-frequency modes may be extremely dangerous because the amplitudes of the responses of the low-frequency modes can be very large compared with those of the directly excited high-frequency modes.

Experimental Studies of Turbulent Flow in a Porous Circular Tube With Uniform Fluid Injection Through the Tube Wall

1966 ◽  
Vol 33 (1) ◽  
pp. 7-17 ◽  
Author(s):  
Reuben M. Olson ◽  
E. R. G. Eckert
Keyword(s):  
Turbulent Flow ◽  
Cross Section ◽  
Mass Velocity ◽  
Tube Wall ◽  
Experimental Studies ◽  
Circular Cross Section ◽  
Axial Position ◽  
Tube Length ◽  
Injection Velocity ◽  
Porous Tube

Fully developed turbulent flow of air at Re = 28,000 to 82,000 entered a porous tube with circular cross section. Air was injected uniformly through the tube wall for 18 diameters at various ratios of mass velocity through the tube wall to the average mass velocity at the entrance cross section of the tube, ranging from 0.00246 to 0.0584. Tests were also made with zero entrance velocity at the upstream end of the porous tube so that the flow developed in the tube exclusively as a result of the uniform mass injection through the tube wall. Most of the change in the shape of the velocity profiles, in the internal and wall shear, in the momentum flux factor, and in the friction factor occurred within the first 10 to 12 diameters of the tube length. Some changes even persisted further downstream, caused by the fact that mass is continuously injected along the porous tube. The parameters mentioned above, however, become independent of axial position for normalized distances downstream from the entrance cross section larger than x/D = 10 to 12, when they are considered as function of the ratio of injection velocity to average main flow velocity at the specific axial location. Eddy diffusivity values agreed in this presentation reasonably with the results of measurements in turbulent tube flow without injection. Normalized friction factors agreed with values measured in external flow. Properly normalized velocity defect profiles with injection agreed with those for flow without injection.

Simpler Estimation of Fracture Toughness during Material Development, Process Optimization and Quality Control of Structural Materials

2012 ◽  
Vol 736 ◽  
pp. 192-206 ◽  
Author(s):  
Kalyan Kumar Ray
Keyword(s):  
Heat Treatment ◽  
Fracture Toughness ◽  
Quality Control ◽  
Cross Section ◽  
Process Optimization ◽  
Volume Fraction ◽  
Circular Cross Section ◽  
Structural Materials ◽  
Microalloyed Steels ◽  
Material Development

Existing standard International methods to estimate fracture toughness of structural materials as documented in ASTM standard E-1820 are neither appropriate for material development due to the requirement of considerable volume nor suitable for process optimizations like deciding suitable heat treatment or for quality control of tonnage materials at the stage of production due to techno-economic reasons owing to their time-consuming nature. This report overviews several investigations often in their feasibility stage and aims to suggest a common solution to all these problems considering measurement of fracture toughness (KIVM) using chevron notched bend bar specimens with either rectangular cross-section (RC) or circular cross-section (CC). At the outset the theoretical background for obtaining KIVMRC and KIVMCC and the corresponding normalized stress intensity factors are discussed in order to illustrate the relatively simpler principle of estimation of fracture toughness. The usefulness of this technique is next illustrated using a number of examples related to: (a) design of small specimens for fracture toughness determination using this principle (b) optimization of the volume fraction of the constituent phases in dual phase steels, (c) design of heat treatment for cast rolls, (d) optimization of cryotreatment for tool steels and (e) study of the effect of inclusions on toughness characteristics of microalloyed steels. The examples related to (a) is for demonstrating the capability of this technique for material development, that related to (b), (c) and (d) are to illustrate its potential for process optimization and the one related to (e) is to illustrate its potential for quality control of tonnage materials.

Pressure Losses in Smooth Pipe Bends

1960 ◽  
Vol 82 (1) ◽  
pp. 131-140 ◽  
Author(s):  
H. Ito¯
Keyword(s):  
Cross Section ◽  
Experimental Studies ◽  
Circular Cross Section ◽  
Empirical Formulas ◽  
Design Problems ◽  
Pressure Losses ◽  
Test Information ◽  
Present Test ◽  
Practical Design ◽  
Smooth Pipe

The results of extensive experimental studies to determine the pressure losses for turbulent flow in smooth pipe bends of circular cross section are presented in this paper. To make the data usable in practical design problems, the results are discussed in relation to those found by previous investigators, and empirical formulas for the bend-loss coefficient are given. The general correlation of the test data appears to be as good as our present test information will permit.

scholarly journals Main results of experimental studies of reinforced concrete structures of high-strength concrete B100 round and circular cross sections in torsion with bending

2019 ◽  
Vol 15 (1) ◽  
pp. 51-61
Author(s):  
Vladimir I Travush ◽  
Nikolay I Karpenko ◽  
Vladimir I Kolchunov ◽  
Semen S Kaprielov ◽  
Alexey I Dem’yanov ◽  
...  
Keyword(s):  
Reinforced Concrete ◽  
Cross Section ◽  
High Strength Concrete ◽  
Crack Opening ◽  
Experimental Studies ◽  
Concrete Structures ◽  
Circular Cross Section ◽  
High Strength ◽  
Reinforced Concrete Structures ◽  
Strength Concrete

Aim of the research to verify the proposed calculating apparatus and accumulate new experimental data on the complex resistance of reinforced concrete structures, experimental studies of such structures made of high-strength concrete of circular and circular cross-section were conducted at the testing base of the South-West State University. Method is experimental-theoretical. Results of experimental research the plots of the deflections and rotation angles, the dependency of deformations of concrete according to the testimony of the outlets of electrodesorption with respect to the calculated cross section 1-1. The main deformations of elongation and shortening of concrete were determined; the reinforcement was selected in such a way that in the stage preceding the destruction, it reached fluidity, so the stresses in the reinforcement are known. It is established that for reinforced concrete structures made of high-strength concrete of circular cross-section, as a rule, there is the development of two cracks, i.e. the round shape of the cross-section slightly reduces the concentration due to the structure of high-strength concrete. For the annular section there were several cracks, of which stands out the one on which the destruction occurs. On the steps preceding the destruction, this crack begins to prevail over the rest and has a maximum opening width. On the basis of experimental studies of reinforced concrete structures made of high-strength concrete of square and box sections, reliable data on the complex stress-strain state in the studied areas of resistance, such as: the values of the generalized load of cracking , and destruction ,, its level relative to the limit load; the distance between the cracks at different levels of cracking (up to the moment of destruction, as a rule, two or three levels are formed); crack widths at the level of the axis of the working armature, at a distance of two diameters from the axes of the armature and along the entire crack profile at various stages of loading, from which it follows that the crack opening at the level of the axis of reinforcement in 2-3 times less compared with the crack opening on the removal of 1.5-2 diameters of the working axis (longitudinal and transverse) reinforcement; the coordinates of the spatial formation of cracks; schematic drawings on tablets of education, development and opening of cracks of reinforced concrete constructions in torsion with bending. Thus, the experimental studies and the result provide an opportunity to test the developed computational model and its working hypotheses for assessing the resistance of reinforced concrete structures made of high-strength concrete in torsion with bending.

SAF file: It's really three dimensional file

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

Experimental Studies Of Multilayer Glass Structures On Compression, Compression With Bending And Simple Bending

2019 ◽  
pp. 22-30
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Applied Load ◽  
Experimental Studies ◽  
Strength Properties ◽  
Research Topic ◽  
Normative Values ◽  
Laminated Glass ◽  
The Cross ◽  
Experimental Values

The work of multilayer glass structures for central and eccentric compression and bending are considered. The substantiation of the chosen research topic is made. The description and features of laminated glass for the structures investigated, their characteristics are presented. The analysis of the results obtained when testing for compression, compression with bending, simple bending of models of columns, beams, samples of laminated glass was made. Overview of the types and nature of destruction of the models are presented, diagrams of material operation are constructed, average values of the resistance of the cross-sections of samples are obtained, the table of destructive loads is generated. The need for development of a set of rules and guidelines for the design of glass structures, including laminated glass, for bearing elements, as well as standards for testing, rules for assessing the strength, stiffness, crack resistance and methods for determining the strength of control samples is emphasized. It is established that the strength properties of glass depend on the type of applied load and vary widely, and significantly lower than the corresponding normative values of the strength of heat-strengthened glass. The effect of the connecting polymeric material and manufacturing technology of laminated glass on the strength of the structure is also shown. The experimental values of the elastic modulus are different in different directions of the cross section and in the direction perpendicular to the glass layers are two times less than along the glass layers.

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