Journal Vol – 17 No -5, May 2022



Bouaraour Kamel, Lalmi Djemoui



This paper, reports the numerical results of the turbulent flow characteristics and turbulent quantities when a triangular object is placed at the exit of two nozzles. The fluid flow at the entrance of the nozzles is considered isothermal and incompressible. Three turbulence k-ε models are used to study the jets interaction and its resulting characteristics. The numerical method is first validated with the available experimental results for a configuration where no object is placed between nozzles. Numerical simulations are carried out for fixed turbulence intensity at the nozzles exit (3%), and for Reynolds numbers varied from 2.103 to 104. Results reveal that the existence of a solid object between the dual jets affects the location of the merge and combined points. The merge point is pushed downstream of the flow, and the corresponding axial velocity of the combined point is reduced for all Reynolds numbers. The turbulent kinetic energy field is also affected, either in the near field or in the far field for all Reynolds numbers. We have concluded also that the Realizable k-ε model overestimates velocity and turbulent kinetic energy fields compared to the other models.


flow interaction,merge point,combined point,turbulence model,


I. Abbasalizadeh M., Jafarmadar S. and Shirvani H., “The effects of pressure difference in nozzle’s two phase flow on the quality of exhaust mixture”, International Journal of Engineering Transactions B: Applications, vol. 26, no. 5, pp: 553-562, 2013.
II. Anderson E. A. and Spall R. E., “Experimental and numerical investigation of two-dimensional parallel jets”, Transactions of ASME, Journal of Fluids Engineering, vol. 123, no. 2, pp: 401-406, 2001.
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V. Elbanna H., Sabbagh J. A. and Rashed M. I. I, “Interception of two equal turbulent jets”, AIAA Journal, vol. 23, no. 7, pp: 985-986, 1985.
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IX. Hnaien N., Marzouk Khairallah S., Ben Aissia H and Jay J, “Numerical study of interaction of two plane parallel jets”, International Journal of Engineering TRANSACTIONS A: Basics, vol. 29, no. 10, pp: 1421-1430, 2016.
X. Karnam A., Baier F., Gutmark E. J., Jeun J., Wu G. J. and Lele S. K., “An investigation into flow field interactions between twin supersonic rectangular jets”, AIAA Scitech forum, January 2021.
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XXI. Sourav S., Hossain Rifat A. and Taher Ali M. A., “Effects of Reynolds number on twin circular jets at a small space ratio”, International Journal of Research and Scientific Innovation, vol. 7, no. 8, pp: 248-252, 2020.
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XXVII. Zheng X., Jian X., Wei J. and Wenzheng D., “Numerical and experimental investigation of near-field mixing in parallel dual round jets”, International Journal of Aerospace Engineering, vol. 1, pp: 1-12, 2016.

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D. S. Jenaris, K. Hari Ram, D. S. Manoj Abraham, R. Rethan Raj, G. Satish Pandian, N. Ramanan



This work primarily focuses on the polymer matrix composite comprising Nylon 6 and Basalt fibre pooled together for the purpose of wear reduction in spur gear material. The method employed here using the Nylon 6 and Basalt fibre is employed through the Injection Moulding method, the fibres are combined in the ratio of (80:20) & (70:30). This project aims to focus on the mechanical properties such as tensile, compression, and impact test as per ASTM standards. Later Finite Element models were then developed to simulate the impact, tensile, and wear characteristics behavior of the tested material,


Compressive Strength,Split Tensile Strength,GGBS,Metakaoline,Regression Analysis,


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II. K. Mao, W. Li, C. J. Hooke, and D. Walton, “Polymer gear surface thermal wear and its performance prediction,” Tribol. Int., vol. 43, no. 1–2, pp. 433–439, 2009.

III. K. Mao, W. Li, C. J. Hooke, and D. Walton, “Friction and wear behaviour of acetal and nylon gears,” Wear, vol. 267, no. 1–4, pp. 639–645, 2009.

IV. K. Mao, P. Langlois, Z. Hu, K. Alharbi, X. Xu, M. Milson, W. Li, C. J. Hooke, and D. Chetwynd, “The wear and thermal mechanical contact behaviour of machine cut polymer gears,” Wear, vol. 332–333, pp. 822–826, 2015

V. M. C. S. Ribeiro, S. P. B. Sousa, and P. R. O. Nóvoa, “An investigation on fire and flexural mechanical behaviors of nano and micro polyester composites filled with SiO 2 and Al 2 O 3 particles,” Mater. Today Proc., vol. 2, no. 1, pp. 8–19, 2015.

VI. S. Xue and I. Howard, “Dynamic modelling of flexibly supported gears using iterative convergence of tooth mesh stiffness,” Mech. Syst. Signal Process., pp. 1–22, 2016.

VII. S. Senthilvelan and R. Gnanamoorthy, “Effect of rotational speed on the performance of unreinforced and glass fiber reinforced Nylon 6 spur gears,” Mater. Des., vol. 28, no. 3, pp. 765–772, 2007.

VIII. V. Savaria, F. Bridier, and P. Bocher, “Predicting the effects of material properties gradient and residual stresses on the bending fatigue strength of induction hardened aeronautical gears,” Int. J. Fatigue, pp. 1–39, 2015.

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Akter Hossain, Sarder Firoz Ahmmed



 In this article, the effect of temperature-dependent viscosity (TVD) on the unsteady laminar flow and heat transfer (HT) of a viscous incompressible fluid due to a rotating disc (RD) has been investigated numerically by exploiting an in-house numerical code. A set of time-dependent, axisymmetric, and non-linear partial differential equations which govern the fluid flows and heat transfer are reduced to non-linear local non-similarity ordinary differential equations by introducing a newly developed group of transformations for different time regimes. Three different solution methods, such as, (i) perturbation solution method for small t, (ii) asymptotic solution method for large t, and (iii) implicit finite difference method for the entire t regime, have been applied to solve the resulting equations treating t as the time-dependent rotating parameter. The local radial skin friction, tangential skin friction and the heat transfer are computed at the surface of the disc for different numerical parameters, such as, Prandtl number, Pr and the viscosity-variation parameter, e. Besides, the key dimensionless quantities such as velocity and temperature profiles, which are inherently linked with the boundary layer thickness, are presented graphically for different values of e while Pr = 0.72. It is found that the dimensionless radial, tangential and axial velocity profiles decrease as e increases, and consequently, the momentum boundary layer thickness is decreased. On the other hand, the non-dimensional temperature profiles are increased owing to the increasing values of e, and this effect eventually leads to a small increment in the thermal boundary layer thickness.  


Unsteady flow,heat transfer (HT),temperature-dependent viscosity (TDV),laminar flow,rotating disc (RD),


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pp: 103-112, 2019.

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VIII. H. B. Keller, Numerical methods in the boundary layer theory, Annual Annual Review of Fluid Mechanics, vol. 10, pp: 417-433, 1978.

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XVII. M. G. Rogers, G. N. Lance, The rotationally symmetric flow of a viscous fluid in presence of infinite rotating disc, Journal of Fluid Mechics, vol. 7, pp: 617-631, 1960.

XVIII. M. A. Hossain, S. M. Munir, Mixed convection flow from a vertical flat plate with temperature dependent viscosity, International Journal of Thermal Sciences, vol. 39, no. 2, pp: 173-183, 2000.

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International Journal of The rmal Sciences, vol. 40, no. 1, pp: 11-20, 2001.

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Research, vol. 48, pp: 1-25, 2018.

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XXVII. P. R. N. Childs, Rotating flow, 1st Edition, Butterworth–Heinemann, UK, 2010.

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XXXV. W. G. Cochran, The flow due to a rotating disc, Proceedings of the
Cambridge Philosophical Society, vol.30, pp.365-37, 1934.

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Kalyanaraman. R



In this paper, we consider a system with two heterogeneous servers Markovian queue. In which the system breakdown occurs when the system is in busy mode. Immediately the system undergoes repair. After completion of the repair, the system either undergoes optional repair mode or becomes busy mode based on a Bernoulli schedule. It is assumed that the number of repairs follows the Poisson process and the repair periods follow an exponential distribution. The model has been solved in steady-state using the matrix analytic method. Some performance measures and numerical results are obtained.


Markovian queue,heterogeneous server,breakdown,repair,steady-state solution,matrix-Geometric method,


I. Cheng, C.Y., and Liu, H.H., (2010) The-finite – time -period preventive maintenance policies with failiure rate reduction under a warranty consideration, Journal of the Chinese institute of industrial Engineers, v.27, 81-89.
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V. Kalyanaraman, R., and Senthilkumar, R., (2018a) Heterogeneous server Markovian queue with switching of service modes,Annamalai University Science Journal, v.51(1), 1-8.
VI. Kalyanaraman, R., and Senthilkumar, R., (2018b) Heterogeneous server Markovian queue with restricted Admissibility and with Reneging, Mathematical Sciences International Research Journal, v.7 (1), 309-315.
VII. Kalyanaraman, R., and Senthilkumar, R., (2018c) Heterogeneous server Markovian queue with restricted Admissibility of customers,Journal of Applied Mathematics Analysis and Applications, v.7(1), 85-97.
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XXI. Witold BIAŁY and Juraj RUŽBARSKÝ (2018) Breakdown Cause and Effect Analysis. Case Study, Management Systems in Production Engineering, v.26 (2), pp. 83-87.
XXII. Wu, C.H., Lee, W.C., Ke, J.C., and Liu,T.H., (2014) Optimization analysis of on unreliable multi server queue with a controllable repair policy, Computer and Operation research, v.49, pp-83-96.

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Shrinjoy Sen, Tapas Kumar Nandi



In the present work, the preliminary finding of possibilities of heat transfer and pressure drop is reported across the shell and tube arrangement cross-flow heat exchanger. The heat exchanger consists of cold-water flows through the bundle of circular tubes and hot air across the shell. Like in the conventional arrangement, the flow in adjacent rows of tubes is normal to the fluid flow in the shell in the cross-flow arrangement. The three-dimensional turbulent flow region is modelled by employing ANSYS FLUENT 21.0. The standard k-ε model is used to model the turbulence flow. A SIMPLE algorithm scheme is applied to link the pressure and velocity fields inside the domain for air fluids. The heat transfer in the water inside the tubes is represented by a convective boundary condition. The tube flow Reynolds number was fixed at 2200 and the shell flow Reynolds number was varied from 6000 to 10000 in the turbulent zone.  The purpose of this paper is to determine temperature reduction and pressure drop across the tube bundle. The simulation will predict the temperature of the airstream at the heat exchanger exit and the pressure drop. The results indicated that there is a significant amount of temperature drop in the air that releases the heat due to forced convection and temperature drop continues in the turbulent region of the incoming fluid.


Cross flow heat exchanger,Temperature drop,Pressure drop,Turbulent flow,


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III. A.S. Krishnan, P. Gowtham. (2017). Computational study of the staggered and double cross flow heat exchanger, Defence Science Journal, Vol. 67, No. 4, pp. 396-400.
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VI. W.M. Kays, A.L. London. (1984). Compact Heat Exchanger 3rd edition, McGraw-Hill Book Co.

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