Journal of Mechanical Research and Application: 5 (3)

Open Access Article

1 - Welding of Aged hardened Nickel base superalloys
محمد رضا محقق نیا

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Open Access Article

2 - The Effect of Parameters of Winkler-Pasternak Elastic Foundations on Stress Analysis of Rectangular Plates Subjected to a Moving Load
احمدرضا خورشیدوند علی خیری امیر مسعود الله قلی

In this study, the stress analysis of rectangular plates resting on Winkler Pasternak model of elastic foundations under a movingconcentrated load with constant velocity and the impact of parameters related to the elastic foundations on normal stresses areinvestigated. More

In this study, the stress analysis of rectangular plates resting on Winkler Pasternak model of elastic foundations under a movingconcentrated load with constant velocity and the impact of parameters related to the elastic foundations on normal stresses areinvestigated. The strain components are assumed to be linear and the Poisson’s ratio is kept constant. Based on first order sheardeformation theory (FSDT) and by employing Hamilton’s principle, the theoretical equations of motion and boundary conditionsare derived. Dimensionless discrete equations and boundary conditions have been achieved by using two dimensional generalizeddifferential quadrature method (DQM) and Newmark procedure. The convergence and accuracy of the present formulation andmethod of the solution, where possible, are demonstrated by comparing with the work of other investigators. With these results,the effect of Winkler foundation modulus and stiffness of Pasternak shear layer foundations on normal stresses of plates havebeen investigated. The analysis provides for both simply supported and clamped boundary conditions at edges. It is discoveredthat the Pasternak shear layer has a predominant influence over Winkler elastic modulus on the plates. Manuscript profile

Open Access Article

3 - Application of sound analysis in the diagnosis of heart and respiratory diseases
امیرسام جواهریان

In this article, we will introduce the applications of sound processing in heart and respiratory diseases. Sound waves are longitudinal mechanical waves. This wave physics can propagate in solids, liquids and gases. The material particles that transmit this wave More

In this article, we will introduce the applications of sound processing in heart and respiratory diseases. Sound waves are longitudinal mechanical waves. This wave physics can propagate in solids, liquids and gases. The material particles that transmit this wave physics oscillate in the direction of the wave propagation. Longitudinal Biomechanical waves occur in a wide range of frequencies. And meanwhile, the physical frequencies of sound waves are in the range that can stimulate the human ear and brain to hear.This range is approximately 20 Hz to about 20,000 Hz and is called audible range. Longitudinal mechanical waves whose frequency is below of the audible range are called subsonic waves, and those whose frequency is above of this range are called ultrasonic waves.Whenever we hit an object, the layers of air move between our hand and the object, and if these movements are more than 16 times per second, a sound is created. In order to better study the role of speech organs in the production of Persian language phonemes, it first seems necessary to provide brief information on how to produce phoneme or sound.Phoneme or sound is produced by the vibration of air molecules. Vibration means the movement of air molecules from their place in a certain direction and their return to their original place. This physical phenomenon is called a wave. Manuscript profile

Open Access Article

4 - Analysis of Buckling of Functionally Graded Carbon Nanotubes-reinforced Composite Beams in Hygrothermal Environments
زهره مزروعی سبدانی علیرضا شاطرزاده

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Open Access Article

5 - Extraction of the governing equations for steady state and axisymmetric behavior of a porous piezoelectric circular solid plate
علی ابجدی محسن جباری احمد رضا خورشیدوند

Based on the available evidence, porous piezoelectric materials have great potential for the development of smart (active) structures with high strength, high stiffness and light weight such as ceramics and composites. Among the ceramic materials with porous piezoelectr More

Based on the available evidence, porous piezoelectric materials have great potential for the development of smart (active) structures with high strength, high stiffness and light weight such as ceramics and composites. Among the ceramic materials with porous piezoelectric compounds, can be mentioned Lead-zirconate-titanate (PZT), Lead-titanate (PbTiO2), Lead-zirconate (PbZrO3), Barium-titanate (BaTiO3), Cadmium-selenide (CdSe), etc. This study extracts the governing partial differential equations for steady- state and axisymmetric behavior of a circular solid plate is made of an undrained saturated porous piezoelectric hexagonal material symmetry of class 6 mm. The porosities of the plate vary through the thickness; thus, material properties, except poisson’s ratio, are assumed as exponential functions of axial variable z in cylindrical coordinates. Additionally, piezothermoelastic behavior of a circular plate subject to external thermal, mechanical and electrical loads is considered, so various concepts including three-dimensional linear elasticity theory and dielectric theory are used in combination to create a linear piezoelectric model. The extraordinary and special industrial properties of porous piezoelectric materials, their increasing use and the need to know the behavior of these materials, doubles the importance of this research. Manuscript profile

Open Access Article

6 - Technology Selection, Flare Gas Recovery, Environmental Hazards, Fault Tree Analysis, Fuzzy Inference
ابوالقاسم نوبختی صدیق رئیسی کاوه خلیلی دامغانی رویا سلطانی

Burning of substandard gases in refineries causes environmental pollution with nitrogen and sulfur compounds and greenhouse gases and unburned hydrocarbons and is associated with thermal energy losses. Environmental protection and commitment to global treaties has led t More

Burning of substandard gases in refineries causes environmental pollution with nitrogen and sulfur compounds and greenhouse gases and unburned hydrocarbons and is associated with thermal energy losses. Environmental protection and commitment to global treaties has led to the selection of one of the two most well-known technologies of the research goal to introduce an alternative that with the least failure, maximizes environmental protection. The main challenge in conducting this research is the dependence of the breakdowns of the alternative on the operating conditions such as pressure and temperature and the lack of empirical data due to the lack of experience in using them. For such purpose, the Fault Tree Analysis (FTA) method is applied to determine the failure scenarios of each alternative in different modes and using the fuzzy inference system, the probability of failure of each technology is estimated. This study also sets standard limits for relevant values that allow design engineers to make decisions about redesigning or controlling pressure and temperature. The required data for this research has been extracted from one of the refineries in the south of Iran. The results showed that the Water Seal Drum system is on average 8% more suitable than the Fast-Opening Valve system and can operate better under critical pressure and temperature scenarios and has been introduced as a superior flaring system Manuscript profile

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