Journal of Thermal Engineering and Applications vol 3 issue 3

ISSN 2349-8994 (Online)

Journal of

Thermal Engineering

& Applications

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Journal of Thermal Engineering and Applications

ISSN: 2349-8994(online)

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It is my privilege to present the print version of the [Volume 3, Issue 3] of our Journal of Thermal

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STM JOURNALS

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

2. Thermal Analysis (Energy and Exergy) of Crystalline Silicon Solar Photovoltaic Module for Hazy Day Ankit Singh, N.V. Saxena 8

3. Performance Evaluation of an Arbitrary Profiled Vertical Fin in Non Newtonian MediumRavi Kumar Sangewar 20

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 27

5. Thermal Performance Analysis of a Solar Dryer-cum-Air Heater with Modified Absorber Surface Harshita Badal, Ankita Badal, Usha Bajpai 34

ContentsJournal of Thermal Engineering and Applications

JoTEA (2016) 1-7 © STM Journals 2016. All Rights Reserved Page 1

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 2×104 to 4×10

4.

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.



Volume 3, Issue 3

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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.



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 non-

monotonically varying characteristics along the length of fin.

Keywords: Non-Newtonian fluid, Nusselt number, Prandtl number

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.

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

by adopting a power law type relation between

the shear stress and shear deformation [2].

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.

FORMULATION

The fin is assumed to be dissipating heat only

by convection to the isothermal quiescent non-

Newtonian fluid. The physical configuration

of the fin is shown in Figure 1.

.



Volume 3, Issue 3

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Influence of Process Parameters on Temperature

Distribution and Microstructure of Friction Stir Welded

Magnesium Alloy

Piyush Gulati1,2,*, Dinesh Kumar Shukla

1, Gurpreet Singh Phull

2

1Department of Mechanical Engineering, Dr. B.R. Ambedkar National Institute of Technology,

Jalandhar, Punjab, India 2School 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



Volume 3, Issue 3

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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].

ISSN 2349-8994 (Online)

Journal of

Thermal Engineering

& Applications

(JoTEA)

September–December 2016

www.stmjournals.com

STM JOURNALSScientific Technical Medical

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