Three types of solar air heaters were experimentally compared: (1) a simple single pass design (Type I), (2) Type I with an aluminum wire mesh added (Type II), and (3) Type I with aluminum fins added (Type III). Thermal efficiency was highest for Type III at 46.12%, followed by Type II and Type I, showing that adding features to disrupt airflow and increase the heat transfer area, like aluminum wire mesh and fins, improves thermal performance. The study aimed to evaluate designs for maximizing heat collection from solar radiation using a low-cost air heating technology.
Three solar air heater having different absorber areas by er. vikas manushendraVikas Manushendra
In earlier years, the entire world has become completely dependent on relic energies such as natural gas, lubricant and coal. This type of resources are existing in limited amount. These resources has been created by natural processes across millions of years. The whole world is completely dependent upon energy. Energy is the basic part of our daily life. The utilization of energy in different purpose such as heating and cooling homes, schools and businesses. Energy is also used for lighting and appliances. In machinery purpose, energy perform different function such as running our vehicle, flying plane, boat sail and running machine. Energy is the player of new generation wealth and also it is significant component of economic development. In future consideration renewable energy is the main source of energy. The complete world is developing day by day and it requires more and more fuel so all the developing countries are focusing on shortage of fuels and necessity for other energy sources. Solar energy is the best alternative source of energy and also it is pollution free and unlimited energy. Nowadays world, the development of country is calculated by the energy utilization of country, the energy of utilization is completely connected with GDP of Country.
THERMAL PERFORMANCE AND ECONOMICS ANALYSIS OF DOUBLE FLOW PACKED BED SOLAR AI...IAEME Publication
Solar air heater is a type of heat exchanger that transforms solar radiation energy into heat energy. Conventional solar air heaters have poor thermal performance due to high heat losses and low convective heat transfer coefficient between absorber and flowing air. Attempts have been made to improve the thermal performance of conventional solar air heater by employing various design and flow arrangements. Double flow solar air heater with packing is an important and effective design improvement that has been proposed to improve the thermal performance. This paper presents the performance and economic analysis of double flow solar air collector with and without packing in the duct. Effect of various parameters on the thermal performance and pressure drop characteristics has been studied experimentally. The study concludes that double flow arrangement with packing is economical and having short payback period. Also, the thermal performance of double flow solar air heater with packing in upper duct is significantly higher compared to double flow solar air heater without packing and conventional solar air heater.
Three solar air heater having different absorber areas by er. vikas manushendraVikas Manushendra
In earlier years, the entire world has become completely dependent on relic energies such as natural gas, lubricant and coal. This type of resources are existing in limited amount. These resources has been created by natural processes across millions of years. The whole world is completely dependent upon energy. Energy is the basic part of our daily life. The utilization of energy in different purpose such as heating and cooling homes, schools and businesses. Energy is also used for lighting and appliances. In machinery purpose, energy perform different function such as running our vehicle, flying plane, boat sail and running machine. Energy is the player of new generation wealth and also it is significant component of economic development. In future consideration renewable energy is the main source of energy. The complete world is developing day by day and it requires more and more fuel so all the developing countries are focusing on shortage of fuels and necessity for other energy sources. Solar energy is the best alternative source of energy and also it is pollution free and unlimited energy. Nowadays world, the development of country is calculated by the energy utilization of country, the energy of utilization is completely connected with GDP of Country.
THERMAL PERFORMANCE AND ECONOMICS ANALYSIS OF DOUBLE FLOW PACKED BED SOLAR AI...IAEME Publication
Solar air heater is a type of heat exchanger that transforms solar radiation energy into heat energy. Conventional solar air heaters have poor thermal performance due to high heat losses and low convective heat transfer coefficient between absorber and flowing air. Attempts have been made to improve the thermal performance of conventional solar air heater by employing various design and flow arrangements. Double flow solar air heater with packing is an important and effective design improvement that has been proposed to improve the thermal performance. This paper presents the performance and economic analysis of double flow solar air collector with and without packing in the duct. Effect of various parameters on the thermal performance and pressure drop characteristics has been studied experimentally. The study concludes that double flow arrangement with packing is economical and having short payback period. Also, the thermal performance of double flow solar air heater with packing in upper duct is significantly higher compared to double flow solar air heater without packing and conventional solar air heater.
DESIGN, SIMULATION AND ANALYSIS OF A HYBRID-TYPE (PV/T) SOLAR AIR HEATER FOR ...ijiert bestjournal
This paper deals with the numerical analysis of a H ybrid-Type (PV/T) Solar Air Heater and a study on t he effect of various design parameters that enhance th e performance of the system. The heat transfer improvement in general may be achieved by increasin g the heat transfer coefficient or by increasing th e surface area or by increasing both. The main object ive of the present work is to determine the optimum air mass flow rate at which PV/T systems are to be oper ated and to develop an optimal design of a hybrid t ype (PV/T) solar air heater that shows better performan ce at various heat fluxes due to solar radiation. T his study determines the set of design parameters which lead to the best annual yield of the system. In th is study of a hybrid type (PV/T) solar air heater ICEM CFD (ANSYS) is used to obtain the optimum results,there by increasing the efficiency of the system.
A Detailed Review on Artificial Roughness Geometries for Optimizing Thermo-Hy...IJMER
It is well known fact that the heat transfer coefficient between the absorber surface of solar air collector & flowing fluid i.e. air can be improved by providing artificial roughness geometry on heat transfer surface (absorber surface).In this way the Thermal efficiency is increased. But at the same time due to roughness geometry pumping power of solar air collector in increased due to fictional losses in duct. So it necessary to examine the shape, size & flow pattern of various roughness elements to get maximum efficiency with minimum frictional losses. Therefore the selection of roughness geometry has to be based on the parameter that takes into account both Thermal & Hydraulic (friction) performance i.e. Thermo-hydraulic Performance of Solar air collector. Number of roughness elements has been investigated on heat transfer & friction characteristics of solar air collectors. In this paper, reviews of various artificial roughness elements used as passive heat transfer techniques, in order to improve Thermo-hydraulic performance of solar air collectors is reviewed & presented. Correlations developed by various researchers with the help of experimental results for heat transfer & friction factor for solar air collector by taking different roughness geometries are given & these correlations are useful to predict the Thermo-hydraulic performance of solar air collector having roughened ducts. The objective of this paper is also the awareness of effect of various types’ roughness geometries on heat
A heat pipe heat exchanger is a simple device which is made use of to transfer heat from one location to another, using an evaporation-condensation cycle.
A passive solar system heat-driven convection or heat pipes to circulate the working fluid. Passive systems cost less and require low or no maintenance, but are less efficient. Overheating and freezing are major concerns.
An active solar system use one or more pumps to circulate water and/or heating fluid. This permits a much wider range of system configurations.
Introduction
Literature Review
Gap Finding
Objective Function
Parameter and range selection
Reference Setup CAD Design
Prototype making
Real scale setup construction/fabrication and installation
Component of setup
Constructed Setup
Testing and Equipment
Solar air heater from the major component of solar energy utilization system which absorbs the incoming solar radiations , converting it into thermal energy at the absorbing surface , in transferring the energy to a fluid flowing collector. The efficiency of flat plate solar air heater has been found to be low convective heat transfer coefficient between the absorber plate and the flowing air which increases the absorber plate temperature , leading to high heat losses to the environment resulting in low thermal efficiency of such collectors.
Artificial roughness in the form of repeated ribs the most effective and economic way of improving the thermal performance of solar air heater.
From the Literature review we conclude that the Multi V ribs with gap gave highest enhancement in nusselt number , however there was a very high enhancement in friction factor also.
All the research work is done on Single pass SAH so we worked upon the Double pass SAH.
From Literature review we also conclude that by providing turbulence ( Ribs ) the SAH is more efficient than Flat plate SAH.
The major objective of this work is to find out the ways to improve effectiveness of SAH by integration of Artificial Roughness Solar Air Heater By Using Perforated Multi V Ribs with Double Pass Parallel Flow.
The second objective is to come out with new shape and geometry to enhance effectiveness of SAH and compare it with other existing geometries and find out gaps and limitations of that shape.
Equations Used are DITTUS BOELTER and MODIFIED BLASSIUS EQUATION.
Parameters Used are Raynolds Number , Nusselt number , Friction factor and we have to find out variation in between these parameters with respect to other by plotting graphs.
Anemometer
Lux Meter
Digital Thermometer
Tilted U tube Manometer
Mercury Manometer
THERMAL PERFORMANCE OF EVACUATED TUBE AND FLAT PLATE SOLAR COLLECTORS IN NORD...IAEME Publication
In this paper the results of the experiments of measuring the performance of evacuated tube and flat plate type solar collectors in Nordic climate conditions are presented. The measurements of the collectors of a given and equal gross surface area were performed in the test installation
environment. While the azimuth of the collectors was preserved constantly by 180°, the vertical incline was varied in order to identify the most suitable value of the thermal performance
International Journal of Computational Engineering Research(IJCER) ijceronline
nternational Journal of Computational Engineering Research (IJCER) is dedicated to protecting personal information and will make every reasonable effort to handle collected information appropriately. All information collected, as well as related requests, will be handled as carefully and efficiently as possible in accordance with IJCER standards for integrity and objectivity.
A B S T R A C T
In the present paper, an experimental analysis of a solar water heating collector with an integrated latent heat storage unit is presented. With the purpose to determine the performance of a device on a lab scale, but with commercial features, a flat plate solar collector with phase change material (PCM) containers under the absorber plate was constructed and tested. PCM used was a commercial semi-refined light paraffin with a melting point of 60°C. Tests were carried out in outdoor conditions from October 2016 to March 2017 starting at 7:00 AM until the collector does not transfer heat to the water after sunset. Performance variables as water inlet temperature, outlet temperature, mass flow and solar radiation were measured in order to determine a useful heat and the collector efficiency. Furthermore, operating temperatures of the glass cover, air gap, absorber plate, and PCM containers are presented. Other external variables as ambient temperature, humidity and wind speed were measured with a weather station located next to the collector. The developed prototype reached an average thermal efficiency of 24.11% and a maximum outlet temperature of 50°C. Results indicate that the absorber plate reached the PCM melting point in few cases, this suggests that the use of a PCM with a lower melting point could be a potential strategy to increase thermal storage. A thermal analysis and conclusions of the device performance are discussed.
CONTEMPORARY URBAN AFFAIRS (2017) 1(3), 7-12. Doi: 10.25034/ijcua.2018.3672
www.ijcua.com
Performance investigation of a flat plate collector incorporated with differe...eSAT Journals
Abstract In the present study a performance evaluation is conducted between a normal flat plate collector (Solar Air Heater) and a flat plate collector incorporated with Tin material. The normal flat plate collector consists of a sheet metal placed within the casing and the Tin incorporated flat plate collector consists of Tin material which is stationed in the form of tins along with the sheet metal within the casing The temperature and velocity of air was measured by using a Thermocouple and Thermo- anemometer respectively. The performance evaluation is done on the basis of efficiencies produced by the two flat plate collectors for natural convection and forced convection. Index terms: Tin, Collector, Convection
Mini Project : Air cooler cum Water ChillerPranit Khot
the mini project is about air cooler cum water chiller perfoemance and its practical significance this ppt includes brief summary and results of the project
Design of Air Preheater for Solar Dryer for Drying Cerealsijiert bestjournal
This paper expla ins about various factors which are to be considering while designing solar dryer for agriculture products. It includes the major part s like air pre heater,air duct,and cabin for keeping agricultura l products. Out of these parts of air pre heater is important as solar energy is available in attuned form & we have to concentrate it with help of solar collectors. In c ollectors absorber plates are made up of good thermal conductor like copper,aluminium so the plate is get heated due to solar radiation & hence air is h eated by the convection process by forcing the air to flow over absorber plate & this heated air is directed towards the cabin through ducts . After that heated air is made to flow over agri cultural product s specially cereals lying in the cabin which is a closed space having number of trays placed in vertical shell with suitable distance & heated air takes away moisture present in it.
Design of air preheater for solar dryer for drying cerealsSumit Dharmarao
This paper explains about various factors which are to be considering while designing solar
dryer for agriculture products. It includes the major parts like air pre heater, air duct, and
cabin for keeping agricultural products. Out of these parts of air pre heater is important as
solar energy is available in attuned form & we have to concentrate it with help of solar
collectors. In collectors absorber plates are made up of good thermal conductor like copper,
aluminium so the plate is get heated due to solar radiation & hence air is heated by the
convection process by forcing the air to flow over absorber plate & this heated air is directed
towards the cabin through ducts. After that heated air is made to flow over agricultural
products specially cereals lying in the cabin which is a closed space having number of trays
placed in vertical shell with suitable distance & heated air takes away moisture present in it.
DESIGN, SIMULATION AND ANALYSIS OF A HYBRID-TYPE (PV/T) SOLAR AIR HEATER FOR ...ijiert bestjournal
This paper deals with the numerical analysis of a H ybrid-Type (PV/T) Solar Air Heater and a study on t he effect of various design parameters that enhance th e performance of the system. The heat transfer improvement in general may be achieved by increasin g the heat transfer coefficient or by increasing th e surface area or by increasing both. The main object ive of the present work is to determine the optimum air mass flow rate at which PV/T systems are to be oper ated and to develop an optimal design of a hybrid t ype (PV/T) solar air heater that shows better performan ce at various heat fluxes due to solar radiation. T his study determines the set of design parameters which lead to the best annual yield of the system. In th is study of a hybrid type (PV/T) solar air heater ICEM CFD (ANSYS) is used to obtain the optimum results,there by increasing the efficiency of the system.
A Detailed Review on Artificial Roughness Geometries for Optimizing Thermo-Hy...IJMER
It is well known fact that the heat transfer coefficient between the absorber surface of solar air collector & flowing fluid i.e. air can be improved by providing artificial roughness geometry on heat transfer surface (absorber surface).In this way the Thermal efficiency is increased. But at the same time due to roughness geometry pumping power of solar air collector in increased due to fictional losses in duct. So it necessary to examine the shape, size & flow pattern of various roughness elements to get maximum efficiency with minimum frictional losses. Therefore the selection of roughness geometry has to be based on the parameter that takes into account both Thermal & Hydraulic (friction) performance i.e. Thermo-hydraulic Performance of Solar air collector. Number of roughness elements has been investigated on heat transfer & friction characteristics of solar air collectors. In this paper, reviews of various artificial roughness elements used as passive heat transfer techniques, in order to improve Thermo-hydraulic performance of solar air collectors is reviewed & presented. Correlations developed by various researchers with the help of experimental results for heat transfer & friction factor for solar air collector by taking different roughness geometries are given & these correlations are useful to predict the Thermo-hydraulic performance of solar air collector having roughened ducts. The objective of this paper is also the awareness of effect of various types’ roughness geometries on heat
A heat pipe heat exchanger is a simple device which is made use of to transfer heat from one location to another, using an evaporation-condensation cycle.
A passive solar system heat-driven convection or heat pipes to circulate the working fluid. Passive systems cost less and require low or no maintenance, but are less efficient. Overheating and freezing are major concerns.
An active solar system use one or more pumps to circulate water and/or heating fluid. This permits a much wider range of system configurations.
Introduction
Literature Review
Gap Finding
Objective Function
Parameter and range selection
Reference Setup CAD Design
Prototype making
Real scale setup construction/fabrication and installation
Component of setup
Constructed Setup
Testing and Equipment
Solar air heater from the major component of solar energy utilization system which absorbs the incoming solar radiations , converting it into thermal energy at the absorbing surface , in transferring the energy to a fluid flowing collector. The efficiency of flat plate solar air heater has been found to be low convective heat transfer coefficient between the absorber plate and the flowing air which increases the absorber plate temperature , leading to high heat losses to the environment resulting in low thermal efficiency of such collectors.
Artificial roughness in the form of repeated ribs the most effective and economic way of improving the thermal performance of solar air heater.
From the Literature review we conclude that the Multi V ribs with gap gave highest enhancement in nusselt number , however there was a very high enhancement in friction factor also.
All the research work is done on Single pass SAH so we worked upon the Double pass SAH.
From Literature review we also conclude that by providing turbulence ( Ribs ) the SAH is more efficient than Flat plate SAH.
The major objective of this work is to find out the ways to improve effectiveness of SAH by integration of Artificial Roughness Solar Air Heater By Using Perforated Multi V Ribs with Double Pass Parallel Flow.
The second objective is to come out with new shape and geometry to enhance effectiveness of SAH and compare it with other existing geometries and find out gaps and limitations of that shape.
Equations Used are DITTUS BOELTER and MODIFIED BLASSIUS EQUATION.
Parameters Used are Raynolds Number , Nusselt number , Friction factor and we have to find out variation in between these parameters with respect to other by plotting graphs.
Anemometer
Lux Meter
Digital Thermometer
Tilted U tube Manometer
Mercury Manometer
THERMAL PERFORMANCE OF EVACUATED TUBE AND FLAT PLATE SOLAR COLLECTORS IN NORD...IAEME Publication
In this paper the results of the experiments of measuring the performance of evacuated tube and flat plate type solar collectors in Nordic climate conditions are presented. The measurements of the collectors of a given and equal gross surface area were performed in the test installation
environment. While the azimuth of the collectors was preserved constantly by 180°, the vertical incline was varied in order to identify the most suitable value of the thermal performance
International Journal of Computational Engineering Research(IJCER) ijceronline
nternational Journal of Computational Engineering Research (IJCER) is dedicated to protecting personal information and will make every reasonable effort to handle collected information appropriately. All information collected, as well as related requests, will be handled as carefully and efficiently as possible in accordance with IJCER standards for integrity and objectivity.
A B S T R A C T
In the present paper, an experimental analysis of a solar water heating collector with an integrated latent heat storage unit is presented. With the purpose to determine the performance of a device on a lab scale, but with commercial features, a flat plate solar collector with phase change material (PCM) containers under the absorber plate was constructed and tested. PCM used was a commercial semi-refined light paraffin with a melting point of 60°C. Tests were carried out in outdoor conditions from October 2016 to March 2017 starting at 7:00 AM until the collector does not transfer heat to the water after sunset. Performance variables as water inlet temperature, outlet temperature, mass flow and solar radiation were measured in order to determine a useful heat and the collector efficiency. Furthermore, operating temperatures of the glass cover, air gap, absorber plate, and PCM containers are presented. Other external variables as ambient temperature, humidity and wind speed were measured with a weather station located next to the collector. The developed prototype reached an average thermal efficiency of 24.11% and a maximum outlet temperature of 50°C. Results indicate that the absorber plate reached the PCM melting point in few cases, this suggests that the use of a PCM with a lower melting point could be a potential strategy to increase thermal storage. A thermal analysis and conclusions of the device performance are discussed.
CONTEMPORARY URBAN AFFAIRS (2017) 1(3), 7-12. Doi: 10.25034/ijcua.2018.3672
www.ijcua.com
Performance investigation of a flat plate collector incorporated with differe...eSAT Journals
Abstract In the present study a performance evaluation is conducted between a normal flat plate collector (Solar Air Heater) and a flat plate collector incorporated with Tin material. The normal flat plate collector consists of a sheet metal placed within the casing and the Tin incorporated flat plate collector consists of Tin material which is stationed in the form of tins along with the sheet metal within the casing The temperature and velocity of air was measured by using a Thermocouple and Thermo- anemometer respectively. The performance evaluation is done on the basis of efficiencies produced by the two flat plate collectors for natural convection and forced convection. Index terms: Tin, Collector, Convection
Mini Project : Air cooler cum Water ChillerPranit Khot
the mini project is about air cooler cum water chiller perfoemance and its practical significance this ppt includes brief summary and results of the project
Design of Air Preheater for Solar Dryer for Drying Cerealsijiert bestjournal
This paper expla ins about various factors which are to be considering while designing solar dryer for agriculture products. It includes the major part s like air pre heater,air duct,and cabin for keeping agricultura l products. Out of these parts of air pre heater is important as solar energy is available in attuned form & we have to concentrate it with help of solar collectors. In c ollectors absorber plates are made up of good thermal conductor like copper,aluminium so the plate is get heated due to solar radiation & hence air is h eated by the convection process by forcing the air to flow over absorber plate & this heated air is directed towards the cabin through ducts . After that heated air is made to flow over agri cultural product s specially cereals lying in the cabin which is a closed space having number of trays placed in vertical shell with suitable distance & heated air takes away moisture present in it.
Design of air preheater for solar dryer for drying cerealsSumit Dharmarao
This paper explains about various factors which are to be considering while designing solar
dryer for agriculture products. It includes the major parts like air pre heater, air duct, and
cabin for keeping agricultural products. Out of these parts of air pre heater is important as
solar energy is available in attuned form & we have to concentrate it with help of solar
collectors. In collectors absorber plates are made up of good thermal conductor like copper,
aluminium so the plate is get heated due to solar radiation & hence air is heated by the
convection process by forcing the air to flow over absorber plate & this heated air is directed
towards the cabin through ducts. After that heated air is made to flow over agricultural
products specially cereals lying in the cabin which is a closed space having number of trays
placed in vertical shell with suitable distance & heated air takes away moisture present in it.
STUDY OF HEAT TRANSFER ON BROKEN ARC ROUGHNESS ELEMENTS ON THE ABSORBER PLATE...IAEME Publication
Performance of solar air heater can be enhanced by adding roughness to the inner periphery. The present study on the effect of various shape parameters for broken arc roughness elements of heat transfer and friction factor characteristics of rectangular duct. The duct has Reynolds number (Re) range of 3000-22300, respective roughness height (e/D) values is 0.045, arc angle (α) is 60˚ and roughness width (W/w) is 5 and relatively roughness pitch is 8.
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
Efficiency Analysis For an Experimentally Set-up Double-Pass V-Corrugated Sol...Aakanksha Dubey
This paper presents the efficiency analysis of an experimental set-up double-pass V-corrugated solar air heater. All
the experimental results were obtained with the developed solar air heater kept at an inclination angle of 23.5
degrees (Latitude Angle of Bhopal, India), facing due south, and using DC fans (for forced convection) with
different air flow rates. The efficiency results, gathered on two consecutive typical Indian peak summer days, are
presented taking into consideration the intermittent availability of sunlight at different times on these days. All the
relevant design aspects of the developed double-pass V-corrugated solar air heater such as the material used for
insulation, construction of the outer enclosure, and the solar air heater assembly, are discussed.
The Effects of Tempered Glass with Low Iron Oxide (Fe2O3) Content on the Effi...IJERD Editor
In this study, the effect of glass cover on the energy and exergy efficiencies of conventional type solar air heater was investigated experimentally. Classic and tempered low iron glass were used as a glass cover. Two of collectors whose dimensions are 900x1900x170mm3 were used in the experiments. The experiments were conducted at the air flow rates of 0.02, 0.03, 0.04 and 0.05 kg/s. Energy and exergy efficiencies were evaluated regarding to experimental results. As a result of the experiments, it was found that energy efficiency of the collector equipped with tempered glass with low iron oxide content increases by an amount of 4.5%-5.3%. In case of exergy efficiency, an increase was also observed between 0.4 and 0.82 percent
Performance of solar air heater system using different shapes of turbulators ...IJECSJournal
This paper presents a performance analysis of three types of turbulators i.e V-shaped, Square shaped and Transverse wedge shaped turbulator on absorber plate of solar air heater system and are compared with flat plate collector. Effects of different turbulators on absorber plate of solar collector are studied and results are found out. The performance of turbulator used in this experimentation is evaluated in terms of heat transfer, Reynolds number, Nusselt number, Friction factor etc. The results shows that transverse wedge shaped turbulator have remarkable heat transfer enhancement and high Reynolds number as well as Nusselt number. It is also observed that heat transfer from transverse wedge shaped rib is more than that of flat plate collector.
Solar air heater : Thermal performance analysis.pptxPrashant18538
Solar air heaters are one of the important devices to utilize solar energy. It is an important device to convert solar energy into heat energy economically.
Similar to Three solar air heater having different absorber areas by Er. Vikas Manushendra (20)
Solar air heater : Thermal performance analysis.pptx
Three solar air heater having different absorber areas by Er. Vikas Manushendra
1. Dissertation Report on
“A COMPARATIVE EXPERIMENTAL STUDY OF THERMAL PERFORMANCE
OF THREE SOLAR AIR HEATERS HAVING DIFFERENT ABSORBER AREA’’
In partial fulfillment for the award of degree of
MASTER OF TECHNOLOGY
In
MECHANICAL ENGINEERING
With specialization
ENERGY ENGINEERING
Centre of excellence, Solar energy research and utilization
1
SURESH GYAN VIHAR UNIVERSITY
JAIPUR
BY
VIKAS KUMAR
Guided By
Mr. HARI KUMAR SINGH
2. INTRODUCTION 2
Solar air heaters are unique type of heat interchange that absorb and
converts solar radiant energy into heat.
The main focus is on the use of Renewable energy.
It is pollution free device and very much environment friendly.
It provide a healthy environment with low cost air heating.
Basically solar air heaters are classified in the following
two categories:
a. Air heaters with porous absorbers and
b. Air heater with non porous absorber
Ceof
solar collector and the cost of equipment is very less as compare to
3. PROBLEM FORMULATION
3
In earlier year the entire world has become more and more dependent on
fossil fuels such as coal , oil and natural gas.
These resources are limited and it is created by natural processes over
millions of years.
The whole world focusing on Shortage of fuel and emphasizes the need
for alternate energy sources.
The Solar energy is one of the low cost and easily available energy
source in the world.
Solar energy is most pollution-free and limitless source
4. OBJECTIVE 4
To compare the thermal efficiency of three different solar air heaters, type-
I, type II and type III respectively.
To investigate the effect of mass flow rate in thermal efficiency of solar air
heater.
To show aluminum wire mesh and aluminum fins ensure more air flow
above and below the absorber plates, generate the turbulence and decrease
the dead zones in the collector.
To prove solar air heater as potential device for harnessing energy from the
sun.
5. MATERIALS & METHODS 5
Components of solar air heater:
The main component of solar air heater are following:-
The casing or container
Insulation
Absorber plate
Cover plate
Fan
Stand
6. The casing or container 6
It is made by strong plywood box.
The thickness of plywood was 12mm.
The internal dimension of box was 1476mm×726mm×186mm
Casing of plywood box
It is made by strong plywood box.
The thickness of plywood was 12mm.
The internal dimension of box was 147686
7. Insulation
7
The thermo Cole and aluminum sheet were used (Scientific name
Polystyrene) for insulating the plywood box from sides and bottom.
The insulation is necessary for the solar air heater for minimizing the heat
loss from sides and bottom of the collector box.
Thermo Cole for insulation
8. Absorber plate
8
The aluminum sheet of 22 gauge thickness were used for absorber plate.
The sheet was painted by black dark rubber coating for absorbing heat
and provides durability.
absorber plate before coated absorber plate after coated
9. Cover plate 9
The two normal transparent window glass cover of 5 mm thickness were
used for cover plate.
The length of glass cover was 1474 mm and width was 723 mm so that it
could sit over container box.
Thermal conductivity of glass is 0.96W/m K
Glass cover used for solar air heater
10. Fan 10
The two computer exhaust fan of 12v each were used to force the air
through the collector.
It was connected by voltage divider to regulate and maintain the speed
of fans.
Fans used for inlet of solar collector
11. Stand
11
The SAHs stand were making by 260
slope shape rectangular stand to
sit the SAHs.
stand for holding SAHs at an angle
12. Measuring instruments 12
Following measuring instruments used for experiment:
LM-35 temperature sensor
Digital (TENMARS TM- 207)
Digital anemometer (METRAVI AVM-05)
alcohol thermometer
Magnetic base
13. Magnetic bas for measuring tilt angle of SAHsDigital anemometer (METRAVI AVM-05)
Digital solar power meter (TENMARS TM- 207)
LM-35 temperature sensor
13
14. Technical specification of
measuring instruments
LM-35
Model- LM-35
Accuracy
0.5 ensured
Temp. operating
-55o
C to 150o
C
Operating from
4V to 30V
Less than
60 Aᵤ
Solar power
meter
Model – LM-100
Accuracy
-3% to 3% at 2854K
Range
20 to 2000 foot
candles
Resolution
0.01 fc/lux
Temperature
-10 o
C to 55o
C
Sensor
Silicon Photodiode
Alcohol
thermometer
Accuracy
1 o
C
Range
-10 to 100 o
C
Organic liquid
Mercury
Glass used
Normal
14
15. Experimental set-up
15
In this experiment following three types of solar air heaters were employed:
1. Simple single pass solar air heater (Type I)
2. Single pass solar air heater having aluminum
wire mesh (Type II)
3. Single pass SAHs having aluminum fins (Type
III)
17. 17Type II Type III
Aluminum wire mesh used in absorber plate
of Type II SAHs
Aluminum fins inserting on absorber plate of
Type III SAHs
18. Calculation 18
The thermal efficiency of all three types, I, type II and type III solar air
heaters, were calculated using equation :
η = Cṁ p (Ta, out – Ta, in)/I Ac
Where, ṁ = mass flow rate (kg/s)
Cp = Specific heat of air at constant pressure (kJ/kg K)
Ta, out = Temperature of air at outlet
Ta, in = Temperature of air at inlet
I = Solar radiation (W/m2
)
Ac = Surface area of the collector (m2
)
19. 19Energy
losses
1/U = 1/ha + dx1 / k1 + dx2 /k2
Where,
dx1 = Thickness of thermo Cole
dx2 = Thickness of plywood
k1 = Thermal conductivity of thermo Cole
k2 = Thermal conductivity of plywood
ha = Convective heat transfer coefficient for air
Q = UA∆T
Qtotal = Qsides + Qtop + Qbottom
Qtotal = 98.88 Watt
Total losses from Sun = 21600 kJ
Total gain = 20318 kJ
20. RESULT & DISCUSSIONS
20
Simple single pass solar air heater (Type I) at exit air
velocity is 4.20 m/s on May 30, 2015
1. The highest daily solar flux is obtained as 965 W/m2.
2. Daily mean solar flux is measured as 800 W/m2
.
3. The difference between the exit and inlet temperature is measured by 33°C.
22. Single pass solar air heater having aluminum wire mesh
(Type II) at exit air velocity is 4.20 m/s on June 05,2015 22
The highest daily solar flux is obtained as 995 W/m2
.
Daily mean solar flux is measured as 805 W/m2
.
The mean thermal efficiency is calculated as 43.26%.
The difference between the mean daily exit and inlet temperature is
measured as 31°C.
23. Single pass solar air heater having aluminum fins
(Type III) at exit air velocity is 4.20 m/s on June 15,
2015
23
The highest daily solar flux is obtained as 1025 W/m2
.
Daily mean solar flux is measured as 871 W/m2
.
The mean thermal efficiency is calculated as 41.44%.
The difference between the mean daily exit and inlet temperature is
measured as 33°C.
25. Thermal efficiency comparison graph of Type I,
Type II and Type III solar air heaters at exit air
velocity 4.20 m/s
25
26. CONCLUSIONS
26
Single pass solar air heaters having aluminum fins higher thermal efficiency
compare to single pass solar air heaters and single pass SAHs with aluminum
wire mesh.
Single pass solar air heater with aluminum wire mesh and aluminum fins has
improved thermal efficiency as wire mesh and fins increase the heat transfer
area.
The maximum mean thermal efficiency obtained as 46.12% in single-pass
solar air heater with aluminum fins (Type III) at exit air velocity 4.20 m/s.
The maximum peak thermal efficiency obtained as 46.12% in single-pass
solar air heater with aluminum fins (Type III) at exit air velocity 4.20 m/s.
The wire mesh and fins or obstacles guarantee a superior air flow above and
below the absorber plates, generate the turbulence and decrease the dead
zones in the collector.