Journal of Thermal Engineering and Applications vol 3 issue 3 by STM Journals

ISSN 2349-8994 (Online)

Journal of Thermal Engineering & Applications (JoTEA) Septemberâ&#x20AC;&#x201C;December 2016

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Journal of Thermal Engineering and Applications ISSN: 2349-8994(online)

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Thermodynamics

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Transition to turbulence

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Bashar Dan-asabe

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P Balachander

Indian Institute of Technology, Banaras Hindu University Varanasi, India.

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P. R. Tailor

P. Selva Kumar

Department of Mechanical Engineering S. V. National Institute of Technology, Surat India.

Department of Mechanical Engineering, PSN Engineering College, Tirunelveli, India.

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Randip Das

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Satyabhama Bhat

Shailendra Kumar Shukla

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Sudip Kumar Samanta

Professor Thermal Turbomachines Laboratory Department of Mechanical EngineeringIndian Institute of Technology, Madras.

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Ajay Tripathi

Visiting Assistant Professor, Mechanical Engineering, Centre of Excellency Energy, Indian Institute of Technology Jodhpur (IITJ), India.

Rustamji Institute of Technology, BSF Academy, Tekanpur, Gwalior.

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Ahmed Hussein

Suchismita Satapathy

Assist.Prof.College of Engineering, Department of Mechanical Engineering, Babylon University, Babylon City, HIILA , Iraq.

Department of Mechanical Engineering,. National Institute of Technology,. Rourkela-769008, India.

Prakash Ghose School of mechanical Engineering, KIIT University, Bhubaneswar.

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Dr. Varun

Ankur Geete

Mechanical Engg. Deptt. National Institute of Technology Hamirpur, Himachal Pradesh.

Mechanical Engineering Department, Sushila Devi Bansal College of Technology, Indore (M.P.)

Sudhakar Kumarasamy

M. K. Pradhan

Department of Energy, Maulana Azad National Institute of Technology Bhopal.

Department of Mechanical Engineering, Maulana Azad National Institute of Technology, Bhopal.

Deoraj Prajapati

M. Sivasubramanian

Department of Mechanical Engineering, PEC University of Technology, Chandigarh.

Department of Mechanical Engineering, Kalasalingam University, Krishnankoil.

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Dr.Ch.S.N.Murthy

Mechanical Engineering Department, L.D.R.P. Institute of Technology and Research, Gandhinagar.

Department of Mining Engineering National Institute of Technology Karnataka, Surathkal.

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It is my privilege to present the print version of the [Volume 3, Issue 3] of our Journal of Thermal Engineering and Applications (JoTEA), 2016. The intension of JoTEA Journal is to create an atmosphere that stimulates vision, research and growth in the area of Thermal Engineering. Timely publication, honest communication, comprehensive editing and trust with authors and readers have been the hallmark of our journals. STM Journals provide a platform for scholarly research articles to be published in journals of international standards. STM journals strive to publish quality paper in record time, making it a leader in service and business offerings. The aim and scope of STM Journals is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high level learning, teaching and research in all the Scientific, Technical and Medical domains. Finally, I express my sincere gratitude to our Editorial/ Reviewer board, Authors and publication team for their continued support and invaluable contributions and suggestions in the form of authoring write ups/reviewing and providing constructive comments for the advancement of the journals. With regards to their due continuous support and co-operation, we have been able to publish quality Research/Reviews findings for our customers base. I hope you will enjoy reading this issue and we welcome your feedback on any aspect of the Journal.

Dr. Archana Mehrotra Managing Director STM Journals

Journal of Thermal Engineering and Applications

Contents

1. Assessment of Engine Performance with Perforated and Solid Fins Prashant Sharma, Siddhartha Kosti

2. Thermal Analysis (Energy and Exergy) of Crystalline Silicon Solar Photovoltaic Module for Hazy Day Ankit Singh, N.V. Saxena

3. Performance Evaluation of an Arbitrary Profiled Vertical Fin in Non Newtonian Medium Ravi Kumar Sangewar

4. Influence of Process Parameters on Temperature Distribution and Micro Structure of Friction Stir Welded Magnesium Alloy Piyush Gulati, Dinesh Kumar Shukla, Gurpreet Singh Phull

5. Thermal Performance Analysis of a Solar Dryer-cum-Air Heater with Modified Absorber Surface Harshita Badal, Ankita Badal, Usha Bajpai

Journal of Thermal Engineering and Applications ISSN: 2349-8994(online) Volume 3, Issue 3 www.stmjournals.com

Assessment of Engine Performance with Perforated and Solid Fins Prashant Sharma, Siddhartha Kosti* Department of Mechanical Engineering, ShriRam College of Engineering and Management, Banmore, Gwalior, Madhya Pradesh, India Abstract Fins increases the heat transfer from a heat generated device by increasing the surface area of it. Fin with holes or perforated fins increases the surface area available for heat removal but also increases the intensity of the air flow, which further increases the heat removal. A two wheeler engine with fins having circular perforation has been designed in the present work. ANSYS 16.0 has been utilized to solve present analysis. Al6063 and Nickel as a material have been considered to see its effect on the heat transfer rate. Perforation has been done to see its effect on the heat transfer. Results of perforated fin engine have been compared by engine without perforated fins. Time-temperature cooling curve has been plotted and results reveal that perforation increases the heat transfer. From the results it also been noticed that Nickel shows larger heat transfer rate compared to Al6063. Weight analysis has also been conducted in the present work. Engine having perforated fins weigh 1.0772 kg for Al6063 and 3.5507 kg for Nickel, but engine with solid fins weigh 1.0798 kg for Al6063 and 3.5593 for Nickel, which reveals that engine made of Nickel weigh more than three times when compared with engine made of Al6063. Keywords: Fin arrays, Navier-Stokes, Nusselt number, Reynold number

INTRODUCTION All most all the electronic devices today generates large amount of heat, which needed to be cool down. This heat can either be cool by passive ways or by active ways. Fins, also known as extended surface have been most widely used active ways studied and adopted for the cooling of these heat generated systems. Perforations in the fins are the recent topic of research nowadays. Shaeri and Yaghoubi in 2009 [1] numerically studied the fluid flow and turbulent convection heat transfer from solid and perforated fins array. They solved the incompressible Navier-Stokes equation considering air as a working fluid using k-ε RNG turbulence model. They used SIMPLE algorithm for solving the problem for Prandtl number of 0.71 for air. Reynolds number was the governing parameter of the flow problem and has been varied from 2×10 4 to 4×104. They concluded that the flow is steady for solid fin and fin with 1 perforation. They found large average friction drag for fin with perforation. Total drag is higher for solid fin when compared with fin with perforation and

it increases with number of perforation. They found larger fin effectiveness for perforated fins and it increases with number of perforation. They also concluded that the perforated fins are lighter in weight. Shaeri and Yaghoubi in 2009 [2] studied the thermal performance of perforated fins in a heat sink. Three-dimensional heat transfer and fluid flow have been studied by solving the incompressible Navier-stokes equation. They adopted finite volume approach and SIMPLE algorithm for solving the present problem. To discretize the governing equation they adopted second order upwind scheme. They take Reynolds number as a governing parameter whose range is 100– 350. They calculated effectiveness, friction coefficient and thermal performance of the fins with perforation and compared it with the results of fin without perforation.

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Journal of Thermal Engineering and Applications ISSN: 2349-8994(online) Volume 3, Issue 3 www.stmjournals.com

Thermal Analysis (Energy and Exergy) of Crystalline Silicon Solar Photovoltaic Module for Hazy Day Ankit Singh*, N.V. Saxena Department of Thermal Engineering, Millennium Institute of Technology, Bhopal, Madhya Pradesh, India Abstract With the growing population, demand for a renewable energy source has reached to peak level. It is necessary to have that source available easily and in sufficient quantity so that with the diminishing non-renewable source, basic need of energy can be fulfilled. This source can be the all-time available source, ‘solar energy’. Concern of most of the countries is just to make the availability of this source better and cheaper. Researches are ongoing in this field. This paper presents the thermal analysis for 10 W polycrystalline solar photovoltaic module with regard to the first and second laws of thermodynamics by taking analytical and experimental test reading at the energy centre, MANIT, Bhopal, India, on a hazy day of 20 June, 2016. We have to evaluate energy, exergy or availability, and power conversion efficiency of the module. This evaluation depends on parameters like solar intensity, wind speed, module temperature and ambient temperature. Exergetic efficiency of polycrystalline photovoltaic module varied from 10.85 to 1.31% throughout the day. It is clear that PV modules are very promising devices and there exists a lot of scope to further improve their performances. All these evaluations and analyses will result to give recommendation that will be befitted to improve the efficiency of PV module, along with making it cost effective and more compatible in today’s market. Keywords: Energy efficiency, exergy efficiency, power conversion efficiency, PV module

INTRODUCTION With the growing demand of energy, development of a new or convenient energy source is very important all over the world. It can be in the form of derived energy or from some renewable source that has futuristic value. Energy is the basic need necessarily to be fulfilled in any developing country, as, with the increasing demand and utilizing capacity, the hike in prices of the fuel are reaching beyond limits for one or the other person in developing country. Also in few coming decades, the availability of those fossil reserves is near to get diminished. To switch these depleting sources with some new and effective source, researchers are being carried out in this way. One of the most viable sources that is widely available and from which energy can be obtained in unlimited amount is the Sun. India is highly benefitted and has great scope for generating solar energy because of its geographical location on Earth. This is the reason of India being a tropical country as it receives solar radiation almost

throughout the year, which accounts to about 3,000 h of sunshine per year. This is equal to more than 5,000 trillion kWh. Almost all parts of India receive 4–7 kWh of solar radiation per square meters. States like Andhra Pradesh, Bihar, Gujarat, Haryana, Madhya Pradesh, Maharashtra, Orissa, Punjab, Rajasthan, and West Bengal have great potential for trapping solar energy due to their location. As in our country majority of the population lives in rural areas where electricity is still a big problem, it will be of great benefit to promote solar energy to this region and thus increasing the scope for research. Also, use of solar energy can reduce the use of firewood and dung cakes by rural household [1]. Basics of Photovoltaic Solar Module Photovoltaic modules are used to convert solar radiation into electricity. Modules are made of semiconductor material. They convert incident solar radiation to heat energy by absorbing solar energy.

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Journal of Thermal Engineering and Applications ISSN: 2349-8994(online) Volume 3, Issue 3 www.stmjournals.com

Performance Evaluation of an Arbitrary Profiled Vertical Fin in Non-Newtonian Medium Ravi Kumar Sangewar* Department of Mechanical Engineering, O.P. Jindal Institute of Technology, Raigarh, Chhattisgarh, India

Abstract In this article, the problem of a parabolic profiled fin dissipating heat by natural convection to quiescent non-Newtonian fluid has been solved theoretically. The generalized equations of temperature distribution and heat transfer rates have been generated using the appropriate boundary conditions with different flow behavior index (n). The results obtained from the graphs indicated that there is a significant influence of flow behavior index (n) and fin parameter (M) on the local and average heat transfer coefficient. The results further indicated that for a wide range of fin parameters, the local heat transfer coefficients are exhibiting nonmonotonically varying characteristics along the length of fin. Keywords: Non-Newtonian fluid, Nusselt number, Prandtl number

by adopting a power law type relation between the shear stress and shear deformation [2].

INTRODUCTION The outcome of investigations regarding flow of non-Newtonian fluids in modern industries is very important. For example, the calculation of heat transfer is very much essential in designing the components accurately in cosmetic and pharmaceutical industries where non-Newtonian fluids such as molten plastics emulsions and pulps flow.

Aim of present study is to formulate a general equation for a parabolic profile vertical fin dissipating heat to non-Newtonian fluid with flow behavior index (n), which gives temperature distribution on its surface and heat transfer rates.

Cho and Nell, in their study revealed the heat transfer phenomenon for non-Newtonian fluids flowing through the circular pipes [1]. Shenoy et al. theoretically solved the conjugate problem of thermal convection from a fin dissipating heat to non-Newtonian fluid

FORMULATION The fin is assumed to be dissipating heat only by convection to the isothermal quiescent nonNewtonian fluid. The physical configuration of the fin is shown in Figure 1. .

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Journal of Thermal Engineering and Applications ISSN: 2349-8994(online) Volume 3, Issue 3 www.stmjournals.com

Influence of Process Parameters on Temperature Distribution and Microstructure of Friction Stir Welded Magnesium Alloy Piyush Gulati1,2,*, Dinesh Kumar Shukla1, Gurpreet Singh Phull2 1

Department of Mechanical Engineering, Dr. B.R. Ambedkar National Institute of Technology, Jalandhar, Punjab, India 2 School of Mechanical Engineering, Lovely Professional University, Phagwara, Punjab, India

Abstract The effect of processing parameters on temperature distribution and microstructure was evaluated after friction stir welding of AZ31 magnesium alloy plates. Temperature distributions were recorded using thermocouples inserted into the drilled holes. Microstructures of the specimens were evaluated using optical microscopy and grain size and other factors were measured. Microhardness results were evaluated using Vicker’s micro hardness tester. Microstructure results revealed that grain size was reduced and grain structure became fine after friction stir welding. Keywords: Friction stir welding, grain size, microhardness, microstructure, thermocouples

INTRODUCTION Magnesium and its alloys are the lightest of all metal alloys and possess excellent mechanical properties such as high strength to weight ratio and stiffness and also good machinability, therefore are in great demand in automobile industry [1, 2]. However, joining the magnesium alloys is a great challenge, if performed by traditional joining techniques such as GTAW, or GMAW as it leads to defects like hot cracks and porosity deteriorating joint’s mechanical properties. These defects produced by fusion welding processes can be overcome by solid state joining processes [3, 4]. Friction stir welding (FSW) is a solid state joining technique, which is capable of producing defect free joints, especially materials with low melting point [5, 6]. In FSW, a solid rotating tool, harder than the workpiece material, is used to join the plates permanently. The tool consisting of a shoulder and a probe/pin is plunged at a constant rotational speed into the joint line between two butted specimens that are clamped rigidly and is moved longitudinally at a constant welding speed. The combined rotating and plunging action of tool pin and shoulder produces

severe plastic deformation due to frictional heat and hence produces a strong metallurgical joint. The material flows in a stirring motion, thereby elongating the grains and producing a refined grain structure, which effectively responds to this technique to improve the strength and mechanical properties. In friction stir welding, various tool and processing parameters such as tool pin profile, shoulder and pin diameter, rotational speed, welding speed and plunge depth play a major role in producing defect free joints. Many researchers have shown the effect of varying tool profile and size on mechanical and metallurgical properties [7–10]. Since tool shoulder diameter plays a major role in producing frictional heat to produce a good joint, it has also been optimized [11]. The effects of welding speed on mechanical properties of friction stir welded magnesium alloys has also been investigated and it was observed that welding speed has significant influence on the formation of defects and hardness of stir zone and hardness of stir zone [12, 13]. However, effect of processing parameters on temperature distribution, resulting microstructure and grain development can be more explored. In this

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Journal of Thermal Engineering and Applications ISSN: 2349-8994(online) Volume 3, Issue 3 www.stmjournals.com

Thermal Performance Analysis of a Solar Dryer-cum-Air Heater with Modified Absorber Surface Harshita Badal*, Ankita Badal, Usha Bajpai Centre of Excellence in Renewable Energy Education and Research, Department of Physics, University of Lucknow, Lucknow, Uttar Pradesh, India Abstract The use of solar resource for food drying has always been a food preservation technique which has widely been practised in most parts of the world. The solar drying system utilizes solar energy to heat up air and to dry food substance placed in dryer, which is beneficial in reducing wastage of food products and helps in preservation of the same. Unfortunately, some of the methods practised in the rural areas have many disadvantages, one of which is the poor quality of food dried. The paper looks at bringing out a new modified design of a solar dryer, which combines the concept of mirror reflectors for better solar insulation and chimney for creating stack effect for better air movement. The ideas of flat plate and curved surface area and exhaust fan have also been explored. The system is designed for increasing the drying rate of the dryer and removing maximum possible moisture contents. The dryer is designed primarily as an indirect type passive solar dryer. The indirect type passive dryer has an advantage that the products are being protected from the UV radiation and there is less damage from temperature extremes; because in these types of dryers, food is placed in trays without sun exposure in the drying cabinet. Our aim has been not only to improve the performance of dryer but we want some better food products. The results obtained during the test period revealed that the temperatures inside the dryer and the solar collector were much higher than the ambient temperature during most sunshine hours. As a result, we got the collector temperature and dryer temperature higher with mirror reflectors than without mirror reflectors. The drying rate was also increased with mirror reflectors than without mirror reflectors and open drying. The variation of surface area of the absorber plate is also analysed in this paper and the effect of incorporating exhaust fan in the system has also been discussed. The results from this paper will go a long way in solar drying technology and preservation of food products in rural areas of India. Keywords: Solar drying, drying rate, passive dryer, collector area

INTRODUCTION Dry food items are a very important part of our daily life. Many countries and people require dry food items due to the climate conditions of their country because not every plant produces food through a year; we have to store some food for further consumption in off seasons. Dry food can be used or stored for a long time than normal food product; normal food does not last for more than two or three days. So people and scientists have discovered many ways of drying the food; ancient and basic type of food drying is solar drying. Solar drying saves food from spoilage bacteria and keeps its nutrition after drying also. Open sun drying is an old method of drying and very popular among normal household workers [1]. In open air drying, food can be spoiled because of dust dirt and humidity, so,

scientists discovered new methods of solar drying with solar food dryers. These dryers can be categorised as: simple, active, passive, and hybrid type of dryers. These dryers save our food from spoilage, dirt, dust and improve its quality also. The aim of this research is therefore to improve the performance of a passive solar dryer by its designing (using multiple mirror reflectors, modified absorber surface (using flat and curve surfaces), or using better air movement in dryer [2].

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Journal of Thermal Engineering & Applications (JoTEA) Septemberâ&#x20AC;&#x201C;December 2016

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