i-manager's Journal on Mechanical Engineering (JME)


Volume 9 Issue 1 November - January 2019

Research Paper

Thermal Performance Analyses of Concentric Pipe Counter Flow Heat Exchanger at Different Operating Conditions by CFD

Rajendra Pathak* , Ankur Geete**
*Research Scholar, Department of Mechanical Engineering, Sushila Devi Bansal College of Technology, Indore, Madhya Pradesh, India.
**Associate Professor, Department of Mechanical Engineering, Sushila Devi Bansal College of Technology, Indore, Madhya Pradesh, India.
Pathak, R., and Geete, A. (2019). Thermal Performance Analyses of Concentric Pipe Counter Flow Heat Exchanger at Different Operating Conditions by CFD. i-manager’s Journal on Mechanical Engineering, 9(1), 1-12. https://doi.org/10.26634/jme.9.1.14805

Abstract

In this research work, a concentric pipe counter flow heat exchanger (CPCFHEx) is analyzed to optimize the performance at different conditions. CFD analyses are executed and temperature, pressure, velocity, and turbulence profiles are studied through pipes by CFD simulation method. Effectiveness, overall heat transfer coefficients, pressure drops, and change in velocities for CPCFHEx are found. Entropy, exergy, and entransy analyses are also done with different flow rates and inner pipe materials to find optimum operating conditions. After analyses, maximum temperature difference (i.e. 4.688 K) for cold fluid and effectiveness (i.e. 0.1562) are found for copper at low flow rates (i.e. 0.081 and 0.19 kg/s cold/hot) but maximum temperature difference (i.e. 1.595 K) for hot fluid is found for steel at high flow rates (i.e. 0.1 and 0.22 kg/s cold/hot). Maximum rate of heat transfer (i.e. 1.603 W) and overall heat transfer coefficient (i.e. 3.160 W/m2 K) but maximum rates of entropy generation (i.e. 1.144 J/s-K) and exergy destruction (i.e.343.2 J/s) are found for copper at high flow rates. Minimum rate of entransy dissipation (i.e. 19874.925 J-K/s) and entransy dissipation number (i.e. 0.4516) are obtained for steel at high flow rates. High conductive material for pipe and low flow rates of fluids are recommended to get better performance of HExs in terms of rate of heat transfer, effectiveness, entropy generation, and exergy destruction.

Research Paper

A Novel Approach of Turning on Titanium(Ti-6AL-4V) Alloy using NFGMT Coupled with GRA, PCA, and RSM

Sivakoteswararao Katta* , Mihai Dupac**, Baojian Guo***
*Research Scholar, Department of Mechanical Engineering, Acharya Nagarjuna University, Guntur, Andhra Pradesh, India.
**Associate Professor, Department of Mechanical Engineering, RVR&JC College of Engineering, Guntur, Andhra Pradesh, India.
***Associate Professor, Department of Mechanical Engineering, Bapatla Engineering College, Bapatla, Andhra Pradesh, India.
Katta, S., Chaitanya, G., and Shankar, B. R. (2019). A Novel Approach of Turning on Titanium (Ti-6AL-4V) Alloy using NFGMT Coupled with GRA PCA and RSM. i-manager’s Journal on Mechanical Engineering, 9(1), 13-21. https://doi.org/10.26634/jme.9.1.14813

Abstract

The present work attempted to find the impact of proces parameters on turning titanium grade 5 alloys and accurate optimization model for responses, such as cutting force, cutting time, and temperature using Principal Component Analysis (PCA), Gray Relational Analysis (GRA), and (RSM) Response Surface Methodology optimization techniques. Graphene Nanoparticles are used to mix with the vegetable oil based (Soya Bean) cutting fluid. The experiment has been done by using machining parameters, such as feed rate, cutting speed, depth of cut, and an analysis has been made to evaluate the machining parameters for cutting force, cutting time, and temperature based on the actual series of experiments with uncoated carbide tool. The outcomes state that the depth of cut and speed has a greater influence on the values of cutting force and temperature as compared to feed. The predicted results are identical to the experimental values. Since this research is multi-objective, these developed models using RSM and PCA can be used for the evaluation of cutting force, temperature, and cutting time as well.

Research Paper

CFD Analysis on Internally Finned Two Phase Closed Thermosyphon Using Nanofluids

K. Manikanta* , A. Swarna Kumari **
* M.Tech Graduate, Department Of Mechanical Engineering, University Of College Of Engineering, Jawaharlal Nehru Technological University, Kakinada, Andhra Pradesh, India.
** Professor, Department Of Mechanical Engineering, University Of College Of Engineering, Jawaharlal Nehru Technological University, Kakinada, Andhra Pradesh, India.
Manikanta, K., and Kumari, A. S. (2019). CFD Analysis on Internally Finned Two Phases Closed Thermosyphon Using Nanofluids. i-manager’s Journal on Mechanical Engineering, 9(1), 22-30. https://doi.org/10.26634/jme.9.1.14973

Abstract

In recent decades, the compactness of the electronic component continues to increase, the heat generation rates also keep on increasing exponentially. Thermal management plays a critical and essential role in maintaining high efficiency and reliability of electronic components. Several cooling technologies are available, among them heat pipe technology is a very promising thermal management solution in high heat flux applications. Heat pipe technology utilises phase change by latent heat of vaporisation and latent heat of condensation. The two-phase closed thermosyphon (TPCT) is a gravity-assisted wickless heat pipe. Due to high efficiency, reliability, simple structure, and cost effectiveness thermosyphons are being used in many applications. In this present work, the geometrical model of twophase closed thermosyphon with internal fins attached to the condenser section is created using CATIA V5R20 software. The model is simulated using ANSYS FLUENT 15.0 commercial software and the interaction between two phases is modelled using Volume of Fluid (VOF) technique. Further optimization is done to improve heat transfer rate using different types of nanofluids, different aspect ratios, and geometries of internal fins. Heat transfer characteristics like temperature distribution and heat transfer rate are studied and compared for all cases. Simple Thermosyphon with fins and without fins was compared using Silicon Dioxide nanofluid as a working fluid. Among three nanofluids used in this work, silicon dioxide (SiO ) shows higher heat transfer rate in Thermosyphon with spiral fins.

Research Paper

Optimization of Four Wheeler-Disc Brake Rotor Using Couple Field, CFD, Squeal Analysis

V. Y. Varma Nayakar* , A. Swarna Kumari **
* M.Tech Graduate, Department of Mechanical Engineering, University of College of Engineering, Jawaharlal Nehru Technological University, Kakinada, Andhra Pradesh, India.
** Professor, Department of Mechanical Engineering, University of College of Engineering, Jawaharlal Nehru Technological University, Kakinada, Andhra Pradesh, India.
Nayakar, V. Y. V., and Kumari, A. S. (2019). Optimization of Four Wheeler-Disc Brake Rotor Using Couple Field, CFD, Squeal Analysis. i-manager’s Journal on Mechanical Engineering, 9(1), 31-43. https://doi.org/10.26634/jme.9.1.14972

Abstract

Safety is always associated with the effective usage of the braking phenomenon of the automobiles. Disc brakes in fourwheelers compared to solid disc type, ventilated disc brake rotor design helps to cool down the disc from heat generated due to friction with the air vents provided. Frictional heat generation in disc brake which leads to severe negative effects, i.e. thermal cracks, brake fade, premature wear, rotor disc thickness variation, etc. So, the precision of temperature distribution and geometry of the disc brake rotor plays a key role in cooling factor of the disc brake and squeal noise generation during braking also plays a major role in deciding the effectiveness of a disc brake with respect to brake fade. In this study, by changing the geometry of the disc brake rotors is to analyze the thermo-mechanical behaviour of the solid and ventilated disc brakes and using the coupled transient thermal and static structural analysis is performed using Finite Element Methods with the help of ANSYS. It is used to determine the temperature, deformation, stresses, and strain fields established in various models of disc brake rotors. Computational Fluid Dynamics (CFD) analysis is performed to investigate the wall heat transfer coefficient of ventilated disc brake rotors using ANSYS Fluent software. From the above CFD analysis, due to changing of vane shapes, there is a considerable increase (10.25%) in modified straight rectangular vane compared to the rectangular vane in heat transfer coefficient of the rotor. Finally, modal analysis is performed using ANSYS to check the disc brake squeal. By comparing the parameters, i.e. temperature, stress distribution is validated with the analytical results, and thereby the optimized or best disc brake rotor is proposed for the effective usage of braking operation of a four-wheeler.

Review Paper

Effect of Process Parameters on Surface Finish in Single Point Incremental Forming Process-A Review

Narinder Kumar* , R. M. Belokar **
* Research Scholar, Department of Production and Industrial Engineering, Punjab Engineering College, Chandigarh, India.
** Professor, Department of Production and Industrial Engineering, Punjab Engineering College, Chandigarh, India.
Kumar, N., and Belokar, R. M. (2019). Effect of Process Parameters on Surface Finish in Single Point Incremental Forming Process-A Review. i-manager’s Journal on Mechanical Engineering, 9(1), 44-51. https://doi.org/10.26634/jme.9.1.14818

Abstract

Single Point Incremental Forming (SPIF) is an emerging flexible forming process, which makes use of CNC milling machine to create complex parts having low volume production rate without using dedicated dies and tooling. A lot of research on this process has been carried out due to its several advantages like customized parts, economical and higher formability as compared to conventional forming process. To make this process more suitable for industry, it is necessary to overcome some of the challenges that is need some serious attention. In this paper, a systematic literature review is presented that studied the quantitative effect of the process parameters on the surface finish. A roadmap for the selection of experimental parameters on this process is proposed which may act as a reference for the researchers.