Search results

Filters

  • Journals
  • Authors
  • Keywords
  • Date
  • Type

Search results

Number of results: 14
items per page: 25 50 75
Sort by:
Download PDF Download RIS Download Bibtex

Abstract

Coal ash produced from thermal power plants as a substitute for conventional construction material has increased considerably in recent years. In the past, studies on partial replacement of soil were carried out with a single type of ash. Because of the insufficient evidence, limited research has been initiated on the productive usage of Fly and Bottom Ashes. This paper aims to study the properties of these materials and investigate their efficacy in road construction. Laboratory investigations were conducted to assess chemical and physical properties and mechanical performance to evaluate both ash types in pavement construction. The rutting factor is calculated for various combinations of coal ash materials with the addition of polypropylene fiber as a reinforcement in increments of 0.1% of its total weight with an aspect ratio of 200. The analytical tool ANSYS is used to validate the service life, vertical strain and quality of reinforced ash materials.

Go to article

Authors and Affiliations

S.M. Subash
N. Mahendran
M. Manoj Kumar
M. Nagarajan
Download PDF Download RIS Download Bibtex

Abstract

Numerous technological applications use MEMS capacitive sensing technique as a major component, because of their ease of fabrication process, inexpensive and high sensitivity. The paper aims at modeling interdigitated capacitive (IDC) sensing. Virtually observe the contribution of variations in geometrical parameters to sensor efficiency and optimization factor. The sensor design is verified through ANSYS simulations. Results indicate “an efficient but poorly optimized sensor is better than a well-optimized sensor”. It is difficult to detect capacitance in the range of few pF generated using capacitive sensing. How it can be maximized with dimension optimization is focused in this paper.
Go to article

Authors and Affiliations

Vaishali Sanjay Kulkarni
1
Suvarna Sandip Chorage
2

  1. Department of E&TC at AISSMSIOIT-Pune,India
  2. Department of E&TC at BVCOEW-Pune, India
Download PDF Download RIS Download Bibtex

Abstract

The web-tapered I-columns have the capacity to resist the flexural buckling and lateral torsional buckling at a particular location where as in the rest of the member the capacity is lower. There needs a focusing on the nonprismatic members, to find the buckling capacity and standard procedures are to be framed in Indian Code IS 800:2007. This exploratory research explores simulated finite element models covering a total of 60 web tapered column sections having taper ratios (h2/h1) from 1.0 to 3.0 using FEA software ANSYS17.2. With an elaborate Eigenvalue buckling analysis, this research has come up with newer design equation for calculating the buckling load of web tapered I columns. This novel equation could predict the buckling stress for any taper ratio of web tapered I column of any length.

Go to article

Authors and Affiliations

C. Rameshbabu
S. Prabavathy
Download PDF Download RIS Download Bibtex

Abstract

In recent time, as the Chinese consumption level increases, the consumption quantity of high-value fruits, vegetables and seafood products have been increasing year by year. As a consequence, the traffic volume of refrigerated products also increases yearly and the popularization degree of the cold-chain transportation enhances. A low-temperature environment should be guaranteed during transportation, thus there is about 40% of diesel oil should be consumed by the refrigerating system and the cold-chain transportation becomes very costly. This study aimed to explore methods that could reduce the cost of transport packages of refrigerated products. On the basis of the heat transfer theory and the fluid mechanics theory, the heat exchanging process of corrugated cases during the operation of refrigerating system was analyzed, the heat transfer process of corrugated cases and refrigerator van was theoretically analyzed and the heat balance equation of corrugated cases was constructed.

Go to article

Authors and Affiliations

Ying Yu
Download PDF Download RIS Download Bibtex

Abstract

In this paper a two-disc spinning disc reactor for intensified biodiesel synthesis is described and numerically simulated. The reactor consists of two flat discs, located coaxially and parallel to each other with a gap of 0.2 mm between the discs. The upper disc is located on a rotating shaft while the lower disc is stationary. The feed liquids, triglycerides (TG) and methanol are introduced coaxially along the centre line of rotating disc and stationary disc. Fluid hydrodynamics in the reactor for synthesis of biodiesel from TG and methanol in the presence of a sodium hydroxide catalyst are simulated, using convection-diffusion-reaction species transport model by the CFD software ANSYS©Fluent v. 13.0. The effect of the upper disc’s spinning speed is evaluated. The results show that the rotational speed increase causes an increase of TG conversion despite the fact that the residence time decreases. Compared to data obtained from adequate experiments, the model shows a satisfactory agreement.

Go to article

Authors and Affiliations

Zhuqing Wen
Jerzy Petera
Download PDF Download RIS Download Bibtex

Abstract

A rotor-stator spinning disk reactor for intensified biodiesel synthesis is described and numerically simulated in the present research. The reactor consists of two flat disks, located coaxially and parallel to each other with a gap ranging from 0.1 mm to 0.2 mm between the disks. The upper disk is located on a rotating shaft while the lower disk is stationary. The feed liquids, triglycerides (TG) and methanol are injected into the reactor from centres of rotating disk and stationary disk, respectively. Fluid hydrodynamics in the reactor for synthesis of biodiesel from TG and methanol in the presence of a sodium hydroxide catalyst are simulated, using convection-diffusion-reaction multicomponent transport model with the CFD software ANSYS©Fluent v. 13.0. Effect of operating conditions on TG conversion is particularly investigated. Simulation results indicate that there is occurrence of back flow close to the stator at the outlet zone. Small gap size and fast rotational speed generally help to intensify mixing among reagents, and consequently enhance TG conversion. However, increasing rotational speed of spinning disk leads to more backflow, which decreases TG conversion. Large flow rate of TG at inlet is not recommended as well because of the short mean residence time of reactants inside the reactor.

Go to article

Authors and Affiliations

Zhuqing Wen
Jerzy Petera
Download PDF Download RIS Download Bibtex

Abstract

Several modelling techniques are currently available to analyse the efficiency of inter-digital transducers (IDTs) fabricated on piezoelectric substrates for producing surface acoustic wave (SAW) devices. Impulse response method, equivalent circuit method, coupling of modes, transmission matrix method, and numerical techniques are some of the popular ones for this. Numerical techniques permit modelling to be carried out with any number of finger electrode pairs with required boundary conditions on any material of interest. In this work, we describe numerical modelling of SAW devices using ANSYS to analyse the effect of mass loading, a major secondary effect of IDTs on the performance of SAW devices. The electrode thickness of the IDT influences the resonance frequency of the SAW delay line. The analysis has been carried out for different electrode materials, aluminium, copper, and gold, for different substrate materials, barium titanate (BaTiO3), X-Y lithium niobate (LiNbO3), lithium tantalate (LiTaO3), and the naturally available quartz. The results are presented and discussed.
Go to article

Authors and Affiliations

Sheeja P. George
1 2
ORCID: ORCID
Johney Issac
2
Jacob Philip
3

  1. Department of Electronics, College of Engineering, Chengannur, Kerala, India
  2. Department of Instrumentation, CUSAT, Kochi, Kerala, India
  3. Amaljyothi College of Engineering, Kanjirappally, Kottayam, Kerala, India
Download PDF Download RIS Download Bibtex

Abstract

The aim of the considerations presented in the article was a stand-alone groundbased photovoltaic power plant. The article is devoted to the qualitative analysis of some lightning protection configurations. These types of constructions often require an individual look at the design and execution of lightning protection installations, which causes problems with the selection of optimal solutions. These problems relate primarily to the way the lightning rods are arranged to create protection zones, but also to the way they are attached: to the supporting structure for PV modules or as free-standing. Another problem raised in the article is the way how lightning current is discharged from rods to the ground and how it is dispersed there. Due to the vast area of such facilities and the requirements for electrical safety, it is necessary to consider and design a ground system with optimal electrical parameters, but also technical and economic ones. All these elements have their impact on the value of voltages induced in the electrical installation, which is also presented in the content of the article as the magnetic field distribution and calculation of induced voltages in an exemplary configuration. Finally, this article will compare described technical solutions encountered in selecting the best protection method for this type of photovoltaic installation.
Go to article

Authors and Affiliations

Konrad Sobolewski
1
ORCID: ORCID
Emilia Sobieska
1
ORCID: ORCID

  1. Warsaw University of Technology, Faculty of Electrical Engineering, Poland
Download PDF Download RIS Download Bibtex

Abstract

In this investigation, the effective mechanical, coupling and dielectric properties of Macro-fiber-composites (MFCs) consisting of piezo-rod-element constituents are determined using representative volume element method combined with finite element analysis. Experiments are conducted on piezo-bar-element MFCs to understand the applicability of the proposed approach which would later be extended to composites with modified geometric pattern. The longitudinal strains with respect to static deflections of beam and forced displacements under varying electrical loads are measured for the MFCs, and compared with the numerical simulations. Based on the good agreement from the result comparisons of piezo-bar-element MFCs, the effective material properties of piezo-rod-element MFCs are numerically determined based on the RVE approach.
Go to article

Bibliography

[1] R .J. Prazenica, D. Kim, H. Moncayo, B. Azizi, M. Chan, Design, Characterization, and Testing of Macro-Fiber Composite Actuators for Integration on a Fixed-Wing UAV, Proc. of SPIE 9057, 905715-2 (2014).
[2] J.R. Farmer, A comparison of power harvesting techniques and related energy storage issues, Master of Science Thesis, Virginia Polytechnic Institute and State University, May (2017).
[3] J. Schröck, T. Meurer, A. Kugi, Control of a flexible beam actuated by macro-fiber composite patches: II. Hysteresis and creep compensation, experimental results, Smart Mater. Struct. 20, 015016 (2011).
[4] R .B. Williams, Nonlinear Mechanical and Actuation Characterization of Piezoceramic Fiber Composites, PhD Thesis, Virginia Polytechnic Institute and State University, March (2004).
[5] S. Ju, C.H. Ji, Indirect Impact based Piezoelectric Energy Harvester for Low Frequency Vibration, IEEE Transd., USA, 978-1-4799- 8955-3, June 21-25 (2015).
[6] Y. Kuang, M. Zhu, Evaluation and validation of equivalent properties of macro fibre composites for piezoelectric transducer modelling, Compos. Part B-Eng. 158, 189-197 (2019).
[7] Z. Dong, C. Faria, B.P. luymers, M. Hromčí, M. Šebek, W. Desmet, Structure-preserving low-order modeling approach of laminated composite plates integrated with macro-fiber composite transducers for dynamic application, Compos. Struct. 208, 287-297 (2019).
[8] J. Latalski, Modelling of Macro fiber composite piezoelectric active elements in abaqus system, E. I Niezawodnosc-Main. and Relia., December (2011).
[9] M. Khazaee, A. Rezaniakolaie, L. Rosendahl, A broadband macrofiber- composite piezoelectric energy harvester for higher energy conversion from practical wideband vibrations, Nano Energy 76, 104978 (2020).
[10] R .B. Williams, D.J. Inman, Nonlinear Tensile and Shear Behavior of Macro Fiber Composite Actuators, J. Compos. Mater. 38 (2004).
[11] C.S. Guimarães, V.P. Budinger, F.L.S. Bussamra, J.A. Hernandes, Structural Shape Control using Macro Fiber Composite Piezoelectric Sensors and Actuators, Comput. Mech., Argentina, 8263-8279, 15-18 (2010).
[12] Jose M. Simoes Moita, Isidoro F.P. Correia, Cristovao M. Mota Soares, Carlos A. Mota Soares, Active control of adaptive laminated structures with bonded piezoelectric sensors and actuators, CompuStruct. 82, 1349-1358 (2004).
[13] Y.X. Hao, K.F. Zhao, W. Zhang, S.W. Yang, Nonlinear dynamics and dynamic instability of smart structural cross-ply laminated cantilever plates with MFC layer using zigzag theory, Appl. Mathematical Mod (2019). DOI: https://doi.org/j.apm.2019.10.056 (in press).
[14] Shun-Qi Zhang, Ya-Xi Li, Rudiger Schmidt, Modeling and simulation of macro-fiber composite layered smart structures, Comp. Struct 51, (2015).
[15] Satyajit Panda, M.C. Ray, Nonlinear finite element analysis of functionally graded plates integrated with patches of piezoelectric fiber reinforced composite, Finite Elements in Analysis and Design 44, 493-504 (2008)
[16] A. Pandey, A. Arockiarajan, An experimental and theoretical fatigue study on macro fiber composite (MFC) under thermomechanical loadings, Eur. J. Mech. A-Solid (2017). DOI: https://doi.org/10.1016/j.euromechsol.2017.06.005
[17] A. Pandey, A. Arockiarajan, Fatigue study on the sensor performance of Macro Fiber Composite (MFC): Theoretical and experimental approach, Compos. Struct. 174, 301-318 (2017).
[18] A. Pandey, A. Arockiarajan, Performance studies on Macro Fiber composite(MFC) under thermal condition using Kirchhoff and Mindlin plate theories, Int. J. Mech. Sci. (2017). DOI: https://doi.org/10.1016/j.ijmecsci.2017.06.034
[19] K.L. Acosta, S. Srivastava, W.K. Wilkie, D.J. Inman, Primary and secondary pyroelectric effects in macro-fiber composites, Compos. Part B-Eng. 177, 107275 (2019).
[20] D. Tan, P. Yavarow, A. Erturk, Nonlinear elastodynamics of piezoelectric macro-fiber composites with interdigitated electrodes for resonant actuation, Compos. Struct. (2017). DOI: https://doi.org/10.1016/j.compstruct.2017.12.056
[21] Q. Jiao, Ji. Hongli, Q. Jinhao, The synergism of peak to peak value, frequency and superimposed DC bias voltage on electricfield- induced strain of PZT based-macro fiber composites, Ceram. Int. 45, 22067-22077 (2019).
[22] K. Steiger, P. Mokrý, Finite element analysis of the macro fiber composite actuator: macroscopic elastic and piezoelectric properties and active control thereof by means of negative capacitance shunt circuit, IOP Publishing, Smart Mater. Struct. 24, 025026 (2015).
[23] S. Sreenivasa Prasath, A. Arockiarajan, Effective electromechanical response of macro-fiber composite (MFC): Analytical and numerical models, Int. J. Mech. Sci. 77, 98-106 (2013).
[24] Z. Abas, H.S. Kim, L. Zhai, J. Kim, Finite element analysis of vibration driven electro-active paper energy harvester with experimental verification, Adv. Mech. Eng. 22, 1-9 (2015).
[25] I EEE Standards on Piezoelectricity, ANSI/IEEE Standard, The Institute of Electrical and Electronic Engineers, New York, 1988.
[26] S. Sreenivasa Prasath, A. Arockiarajan, Analytical, numerical and experimental electromechanical predictions of the effective properties of macro-fiber composite (MFC), Sensor. Actuat. A-Phy. 214, 31-44 (2014).
[27] M.P. Saravanan, K. Marimuthu, P. Sivaprakasam, Modeling and analysis of dynamic structure with macro fiber composite for energy harvesting, Mater. Today-Proc. (2020). DOI: https://doi.org/10.1016/j.matpr.2020.05.390, 2214-7853 (in press).
[28] Smart-Material Corporation, MFC Datasheet, https://www.smart-material.com/Datasheets.html [29] A. Pandey, A. Arockiarajan, Actuation performance of macro-fiber composite (MFC): Modeling and experimental studies, Sensor. Actuat. A-Phy. 248, 114-129 (2016).
Go to article

Authors and Affiliations

M.P. Saravanan
1
ORCID: ORCID
K. Marimuthu
2
ORCID: ORCID
K. Jayabal
3
ORCID: ORCID

  1. Mohamed Sathak AJ College of Engineering, Chennai, India
  2. Coimbatore Institute of Technology, Coimbatore, India
  3. Indian Institute of Information Technology, Design and Manufacturing, Kancheepuram, Chennai, India
Download PDF Download RIS Download Bibtex

Abstract

The analyses aim to determine aerodynamic force coefficients in the case of airflow around two smooth or rough cylinders positioned at different angles to the direction of wind velocity. Such systems, for instance, may be part of a tubular water slide. The results were compared with the values of the interference coefficient of the cylinders arranged in a row included in Eurocode EN 1991 part 4. The aerodynamic forces of the cylinder systems were determined on the basis of experimental tests conducted in a wind tunnel. To verify the above results, CFD (computational fluid dynamics) simulations were prepared. An important observation is that for the angle of yaw β = 0◦, the negative component of the lift force (lateral) fy is shown, while for the other cases, the situation is opposite and the lateral force points outside the gap (upward). The second is that the results of aerodynamic drag for rough cylinders arranged in a row and calculated according to EN 1991 part 4 may be underestimated. The flow around the pair of smooth cylinders is quite different from that of the rough ones, because during the experiment the first falls into the critical flow regime, while the second has supercritical characteristics.
Go to article

Authors and Affiliations

Agnieszka Padewska-Jurczak
1
ORCID: ORCID
Piotr Szczepaniak
1
ORCID: ORCID
Ryszard Walentyński
1

  1. Faculty of Civil Engineering, Department of Mechanics and Bridges, ul. Akademicka 5, 44-100 Gliwice, Poland
Download PDF Download RIS Download Bibtex

Abstract

Gas emissions from underground sites to the atmosphere depend on many factors. Pressure drops are considered to be the most important. However, emissions can also be observed during the initial phase of the pressure rise, following a previous drop in pressure. On the other hand, gas emissions may not be detected when the pressure drops, especially when a previous pressure rise has taken place. The aim of the research was to determine the role of variations in baric tendency on airflow rate and its direction. To solve this problem a numerical model was built utilizing the Ansys Fluent software package. Subsequently, three scenarios of baric tendency variations were tested: a) rise – drop, b) drop – drop, c) drop – rise. The results showed inert behavior of gases. Under scenario (c), 1 hour after the change in tendency gases still were flowing out to the atmosphere. Considering scenario (a), it was proved that even during a pressure drop gas emissions do not take place, which can be crucial for further determination of the gas hazard at the surface or for assessment of the rate of gas emissions from a particular gas emitter. Scenario (b) merely gave an overview of the process and was mainly used for validation purposes. It gave a maximal CO2 concentration of 2.18%vol (comparable to measurements) and a CO2 mass flow rate 0.15kg/s. Taking into account greenhouse gas emissions this amounted to 514 kg CO2/h.
Go to article

Authors and Affiliations

Paweł Wrona
Aleksander Król
Małgorzata Król
Download PDF Download RIS Download Bibtex

Abstract

The presence of nanoparticles in heat exchangers ascertained increment in heat transfer. The present work focuses on heat transfer in a longitudinal finned tube heat exchanger. Experimentation is done on longitudinal finned tube heat exchanger with pure water as working fluid and the outcome is compared numerically using computational fluid dynamics (CFD) package based on finite volume method for different flow rates. Further 0.8% volume fraction of aluminum oxide (Al2O3) nanofluid is considered on shell side. The simulated nanofluid analysis has been carried out using single phase approach in CFD by updating the user-defined functions and expressions with thermophysical properties of the selected nanofluid. These results are thereafter compared against the results obtained for pure water as shell side fluid. Entropy generated due to heat transfer and fluid flow is calculated for the nanofluid. Analysis of entropy generation is carried out using the Taguchi technique. Analysis of variance (ANOVA) results show that the inlet temperature on shell side has more pronounced effect on entropy generation.

Go to article

Authors and Affiliations

Pavan Kumar Konchada
Vinay Pv
Varaprasad Bhemuni
Download PDF Download RIS Download Bibtex

Abstract

Stepped spillway is hydraulic structure designed to dissipate the excess in kinetic energy at the downstream of dams and can reduce the size of stilling basin at the toe of the spillway or chute. The flow on a stepped spillway is characterisedby the large aeration that can prevent or reduce the cavitation damage. The air entrainment starts where the boundary layer attains the free surface of flow; this point is called “point of inception”. Within this work the inception point is determined by using software Ansys Fluent where the volume of fluid (VOF) model is used as a tool to track the free surface thereby the turbulence closure is derived in the k – ε turbulence standard model. This research aims to find new formulas for de-scribe the variation of water depth at step edge and the positions of the inception point, at the same time the contour map ofvelocity, turbulent kinetic energy and strain rate are presented. The found numerical results agree well with experimental results like the values of computed and measured water depth at the inception point and the numerical and experimental inception point locations. Also, the dimensionless water depth profile obtained by numerical method agrees well with that of measurement. This study confirmed that the Ansys Fluent is a robust software for simulating air entrainment and explor-ing more characteristics of flow over stepped spillways.

Go to article

Authors and Affiliations

Chakib Bentalha
Mohammed Habi
Download PDF Download RIS Download Bibtex

Abstract

This article focuses on the finite element analysis (FEA) of the nonlinear behavior of a layered functionally graded material (FGM) plate as concerns displacement, stresses, critical buckling load and fundamental frequency. The material properties of each layer in an FGM plate are assessed according to a ceramic based simple power law distribution and the rules of mixture. The finite element model of a layered FGM plate is developed using ANSYS®15.0 software. The developed finite element model is used to study the static and dynamic responses of an FGM plate. In this paper, the effects of power law distribution, thickness ratio, aspect ratio and boundary conditions are investigated for central displacement, transverse shear stress, transverse normal stress, critical buckling load and fundamental frequency, and the obtained FEA results are in sound agreement with the literature test data results. Since the FGM is used in a high temperature environment, the FE analysis is performed for the FGM plate under a thermal field and then correlated. Finally, the FGM plate is analyzed under a thermomechanical load by using the current FE concept.

Go to article

Authors and Affiliations

N. Vasiraja
P. Nagaraj

This page uses 'cookies'. Learn more