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Orifice Meters are mechanical devices used to measure gases and liquids flows.
To this end, it is common in literature the incorporation of a correction factor, “C” (Calibration Coefficient), to consider the system not ideality, in other words, the losses for friction.
Thus, gets the basic equation of project (Eq. 1), applied when system has incompressible fluids (1) It is known that “C” factor depends on the type of volumetric meter, geometric relations of meter device, location of pressure taps and fluid flow regime.
In duct entrance, different axial velocities were defined to guarantees a certain Reynolds Number of interest, considering for these the fluid properties (water at 297 K): viscosity (m) and density (r) and the internal diameter pipe (D1).
According to Fig. 8, the location of pressure taps upstream may slightly affect the Calibration Coefficient value (note that the Orifice Meter is located from x = 0.50).

Lee 2,b 1 Solid Mechanics Research Center, School of Aeronautical Science and Engineering, BeiHang University, XueYuan Road No. 37, BeiJing,100083, China 2 Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology, 373-1 Guseong-dong, Yuseong-gu, Daejeon 305-701, Korea (South) a liuhuarui@yahoo.com.cn, bleejungju@kaist.ac.kr Keywords: Scattering, Rayleigh Wave, Whispering Gallery Wave, Guided Wave, Far-field Form Function Abstract.
The pressure ip of the incident plane wave external to the cylinder is presented by ∑ ∞ = ⊥ − = 0 0 ) sin(cos)()( n z n n n i zktnrkJiPp ωθ ε , (1) where αcoskk =⊥ , αsinkkz = , ck /ω= , c is the velocity of the wave in the fluid medium outside the cylinder, 0P is the incident pressure wave amplitude, nε is the Neumann factor ( 1=nε , if 0=n ; 2=nε , if 0>n ), and nJ is the first kind Bessel function of order n.
Then the mechanical stress and the electric displacement components can be obtained by the constitutive relations 3.
Solution of the Problem When a fluid medium is present outside the cylinder, the relatively high permittivity of the fluid like water could possibly affect the electrical boundary conditions.
Due to the fact that some resonances are sensitive to axial properties of the cylinder, while others are sensitive to transverse properties of the cylinder, the resonance scattering theory is able to apply to the nondestructive evaluation field and characterizes the material properties in both axial and transverse directions.

In recent years, new generation nickel-base superalloys, such as René104 (also called ME3) [4], LSHR (Low Solvus, High Refractory alloy) [5], Alloy 10 [6] and N19 (SMO43) [7] are developed; these new alloys are optimized for numerous mechanical and physical properties at the higher temperatures, and also to produce dual microstructure discs (a fine-grain core and a coarse-grain rim), which should have a high potential for optimum performance.
There is more interest in the development of techniques, such as predicting microstructure in forgings and numerical simulation of forging process, in order to obtain the excellent mechanical properties of forging components.
Analysis of the constitutive model For the range of deformation conditions employed in this study, flow stress as a function of both deformation temperature and strain rate is analyzed using a hyperbolic sine Arrhenius-type equation [11,12], which is expressed as follows: (2) with A, a structure factor, a, a stress level parameter, n, a stress index (materials constants), , the strain rate, Q, the activation energy, T, the deformation temperature, s, the flow stress, R, the universal gas constant (8.314J/mol.K).
The micrographs reveal that the deformed microstructure is affected by the deformation conditions, and the recrystallized regions and the grain size increase with increasing deformation temperature and decreasing strain rate.
The full recrystallized fine-grained structure can be obtained after extrusion, which enhances the deformation properties of materials.

The porosity has a greatest effect on the combination property.
But the heat conduction will be affected by the actual contact area between the porous medium and the wall obviously, when the porous medium is inserted into the pipes by some mechanical methods.
The effects of the key parameters, such as Darcy Number, Reynolds Number and porous block geometrical factor on the heat transfer enhancement were analyzed.
To simplify the problem, the following assumptions of this model are made:(1) Sintering porous media material is homogeneous and isotropic, the thermal physical properties of it are constant;(2) the inside solid skeleton of the porous medium and fluids meet local thermal equilibrium;(3) Ignore the influence of gravity;(4) Ignore viscous dissipation's effects of the fluid on temperature field;(5) Fluid is Newtonian fluid and its physical parameters are constant.
However, f/f0 of solid-ring turbulator pipe decreases with increasing Re number and the ratio is about 22 to 26.The friction factor of porous-ring turbulator pipe is about 2 to 3 times of that solid-ring turbulator pipe under the same Re number.

Introduction It is well known that during AIP process droplets are generated, which adhere loosely to the coating surface and significantly affect the performance of the coating [1].
In the meantime, the composition of coatings has significant effect on their mechanical and oxidation resistant properties.
The control of reactive gas is another critical matter for optimization of coating properties [2].
It has been shown that melting point of target materials affects the number and size of Fig. 1.
At elevated temperatures, the formation of TiO2 cluster by outward diffusion of Ti through lattice and defects of the coating, and interdiffusion between (Ti,Al)N coating and steel may be the main factors for the deterioration of the coating.

The study of loess localization shear band does not acquire great achievement for the influence of loess structural properties.
Based on digital photographic measurement and analysis of correlation between images LI Yuan-hai[11] puts forth a recognition method of soil shear band; Sun[12] conducts true triaxial test on dense sand and analyses the influence of different paths on sand softening properties and formation of shear band; Wang[13] analyses the effect of stress state on sand localization deformation through true triaxial test.
WANG Zhu-pin[14] uses fly ash, makes full use of field characteristics of numerical picture measuring technique to analyze shear band modality and stress-strain characteristics of triaxial test samples as well as the forming conditions and influencing factors of shear band.
For structural loess, the existence of heterogeneity and weak element can affect the shear band a lot.
The element will adopt Mohr-Coulomb criterion to judge whether destroyed if breakage ratio is larger than 0.95 in following load steps. 2.3 Failure criterion In order to simulate engineering properties of soil, kinds of failure criterions have been put forward to describe strength of soil.

In particular, the carbide type, morphology, size and distribution pattern in the cast state affect significantly the mechanical properties of HSSs after full heat treatment, primarily their toughness and wear resistance.
In the case of the latter, thickness and continuity of eutectic carbide networks are other important factors impacting the above-mentioned properties.
Thus, the M2C decomposition together with common carbide dissolution results in significant changes in the final microstructure and hence dominantly determines the mechanical properties of HSS after their full heat treatment [17, 18].
Jiang, Morphology and properties of M2C eutectic carbides in AISI M2 Steel, ISIJ Int. 50 (2010) 1151–1157
Chaus, Microstructural and properties evaluation of M2 high speed steel after inoculating addition of powder W and WC, Mater.

Moreover, the capability of simulating and predicting damage phenomena is increasingly important for both structural optimization and the definition of safety factors against strong excitations (i.e. earthquakes, blast or impact loadings).
The material fracture properties are defined in terms of a stress versus crack-opening displacement relation.
In the work of Schlangen and van Mier, a regular pattern of nodal sites was superimposed over images of the internal structure of concrete to assign different mechanical properties to the frame elements representing the different phases: aggregate, matrix, and aggegrate-matrix interface.
The Delaunay tessellation defines the lattice topology; the dual Voronoi tessellation defines the geometrical properties of the elements.
[3] ACI Committee, Fracture Mechanics of Concrete: Concepts, Models and Determination of Material Properties, Elsevier, 1992

And it is accomplished by establishing the mathematical model of mechanical part at first, then establishing the mathematical model of hydraulic system, and finally combining two mathematical models through the output force and displacement of the hydraulic cylinder.
Mathematical modeling of mechanical parts The mechanical part of the test bench consist of the test object, the bearing unit and the elastic element of the front hydraulic cylinder.
According to continuity properties of hydraulic oil and the flow characteristics of the hydraulic cylinder and the servo valve [5,6], we can get the following equation: (2) Where Kq represents the flow gain of the valve, Kc stands for the valve flow-pressure coefficient, PL represents the load pressure of the hydraulic system, QL stands for the load flow, A is the effective area of the double rod piston cylinder, Cip denotes the inside leakage coefficient of the hydraulic cylinder, Cop denotes the external leakage coefficient of the hydraulic cylinder, β is the equivalent bulk modulus of the hydraulic oil, and V0 is the cavity volume of the hydraulic cylinder.
Meantime, its searching for the optimal solution is not affected by initial value.
Journal of Mechanical Engineering, Vol. 6 (2013), p.89-98

The strength of porcelain can be affected by small defects.
Such factors, like voids, porosity, or even micro-cracks may reduce the strength of porcelain.
Wear process may be accelerated by the ceramic restorations whose wear properties differ from those of the tooth structure that they slide against.
Ovecoglu, Physical properties and microstructural characterization of dental porcelains mixed with distilled water and modeling liquid, Dent.
Yoshimura, Mechanical properties and porosity of dental glasses at different temperature, Mater.