hybrid air cooler and warmer report
DESCRIPTION
An innovative air conditioner design with the use of natural energy resourcesTRANSCRIPT
1. INTRODUCTION
Air conditioning has become one of the basic need for mankind to
sustain the hot climatic conditions due to global warming and to sustain
the winter conditions as well. But in a country like India where the
climatic conditions are usually hot, it is necessary to have a cooler in
order to bare the hot conditions. Though there are many air conditioners
invented with various features to overcome this crisis but they all emit
greenhouse gases like Hydro Fluoro Carbon (HFC), Carbon-di-Oxide
(CO2), Hydro Fluoro Ethers (HFE) there by leading to global warming
which in turn increases the surface temperature of the earth’s surface and
also leading several health issues like dehydration, allergies, asthma, and
also most of them run with the help of electricity which is produced with
the help of non-renewable which is depreciating every day form of
energy hence in order to overcome these issues it is necessary to design
an air conditioner with zero emission and minimum energy consumption.
So it is wise to design the modern air conditioner to run with help of
renewable energy and with the capability of converting it into a warmer,
hence our project is designed in a way to compromise these problems.
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1.1 Objective
The main objective of the project is to use the renewable energy
resource to operate the air cooler and to convert it as warmer as well with
the help of heating coil.
1.2 Scope of project
Evaporative cooling systems have the advantage of using harmless
working fluids such as water or solutions of certain salts, they are
environmentally safe. Additionally, producing electricity from renewable
resources can solve the crisis of over consumption of non-renewable
energy resources.
1.3 Project planning
To start of this project, a meeting with the supervisor in the first
week was done to manage the schedule of weekly meetings. The purpose
is to inform the supervisor on the progress of the project and guided by
the supervisor to solve difficulty.
Briefing based on the introduction and next task of the project is
given by supervisor. Make research on the literature review with the
means of the internet, books available, published articles and materials
that is related to the title.
Design phase start of by sketching a few models using manual
sketching on A4 papers. We did so as to make comparison for choosing
the best concept. Software applications were downloaded from internet to
design the model based on the sketches. Software Solid works helped us
to draw better dimensional model.
The preparation of mid-presentation of the project was the next.
Before presenting, the supervisor will see through the slide presentations
and comment on corrections to be made.
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2. TERMINOLOGY OF EVAPORATIVE COOLING SYSTEM
2.1 EVAPORATIVE COOLING SYSTEM
An evaporative cooler is a device that cools air through
the evaporation of water. Evaporative cooling differs from typical air
conditioning systems which use vapour-compression or absorption
refrigeration cycles. Evaporative cooling works by employing water's
large enthalpy of vaporization. The temperature of dry air can be dropped
significantly through the phase transition of liquid water to water vapour
(evaporation), which can cool air using much less energy
than refrigeration. In extremely dry climates, evaporative cooling of air
has the added benefit of conditioning the air with more moisture for the
comfort of building occupants. Air washers and wet cooling towers use
the same principles as evaporative coolers but are designed for purposes
other than directly cooling the air inside a building. For example, an
evaporative cooler may be designed to cool the coils of a large air
conditioning or refrigeration system to increase its efficiency.
2.1.1PRINCIPLE OF EVAPORATIVE COOLING SYSTEM
Fig 2.1 Principle of evaporative cooling system
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Evaporative coolers lower the temperature of air using the principle
of evaporative cooling, unlike typical air conditioning systems which
use vapour-compression refrigeration or absorption refrigerator.
Evaporative cooling is the addition of water vapour into air, which causes
a lowering of the temperature of the air. The energy needed to evaporate
the water is taken from the air in the form of sensible heat, which affects
the temperature of the air, and converted into latent heat. This conversion
of sensible heat to latent heat is known as an adiabatic process because it
occurs at a constant enthalpy value. Evaporative cooling therefore causes
a drop in the temperature of air proportional to the sensible heat drop and
an increase in humidity proportional to the latent heat gain. Vapour-
compression refrigeration uses evaporative cooling, but the evaporated
vapour is within a sealed system, and is then compressed ready to
evaporate again, using energy to do so. A simple evaporative cooler's
water is evaporated into the environment, and not recovered. In an
interior space cooling unit, the evaporated water is introduced into the
space along with the now-cooled air; in an evaporative tower the
evaporated water is carried off in the airflow exhaust.
2.2 SOLAR POWER PRODUCING SYSTEM
Solar power is the conversion of sunlight into electricity, either
directly using Photovoltaics (PV), or indirectly using Concentrated Solar
Power (CSP). Concentrated solar power systems use lenses or mirrors
and tracking systems to focus a large area of sunlight into a small beam.
Photovoltaics convert light into electric current using the photovoltaic
effect. Photovoltaics were initially, and still are, used to power small and
medium-sized applications, from the calculator powered by a single solar
cell to off-grid homes powered by a photovoltaic array. They are an
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important and relatively inexpensive source of electrical energy where
grid power is inconvenient, unreasonably expensive to connect, or simply
unavailable. However, as the cost of solar electricity is falling, solar
power is also increasingly being used even in grid-connected situations as
a way to feed low-carbon energy into the grid.
2.2.1 PHOTO VOLTAIC CELL
Fig. 2.2 Photo voltaic cell
A solar cell also called a photovoltaic cell is an electrical device
that converts the energy of light directly into electricity by
the photovoltaic effect. It is a form of photoelectric cell in that its
electrical characteristics e.g. current, voltage, or resistance vary when
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light is incident upon which, when exposed to light, can generate and
support an electric current without being attached to any external voltage
source, but do require an external load for power consumption.
2.3 WIND POWER PRODUCING SYSTEM
To extract energy from wind and to convert that energy into
electrical power, we need a Wind Turbine setup which can convert the
mechanical power into electrical power. The blades of the wind turbine
are fixed to the rotor part of the generator set which is mounted on the
turbine using gear-arrangement. Wind with a speed of 5km/hr or more
causes the rotation of the blades of the turbine. As the blades rotate, the
mechanical power then converts into electrical power with the help of
generator set.
2.3.1 WIND TURBINE
Fig 2.3 Wind turbine
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A wind turbine is a device that converts kinetic energy from
the wind into electrical power. A wind turbine used for charging batteries
may be referred to as a wind charger. The result of over a millennium of
windmill development and modern engineering, today's wind turbines are
manufactured in a wide range of vertical and horizontal axis types. The
smallest turbines are used for applications such as battery charging for
auxiliary power for boats or caravans or to power traffic warning signs.
Slightly larger turbines can be used for making small contributions to a
domestic power supply while selling unused power back to the utility
supplier via the electrical grid. Arrays of large turbines, known as wind
farms, are becoming an increasingly important source of renewable
energy and are used by many countries as part of a strategy to reduce
their reliance on fossil fuels. Not all the energy of blowing wind can be
harvested, since conservation of mass requires that as much mass of air
exits the turbine as enters it. Betz' law gives the maximal achievable
extraction of wind power by a wind turbine as 59% of the total kinetic
energy of the air flowing through the turbine.
Further inefficiencies, such as rotor blade friction and drag,
gearbox losses, generator and converter losses, reduce the power
delivered by a wind turbine. Commercial utility-connected turbines
deliver about 75% of the Betz limit of power extractable from the wind,
at rated operating speed. Efficiency can decrease slightly over time due to
wear, while the other half saw a production decrease of 1.2% per year.
Wind turbines are designed to exploit the wind energy that exists at
a location. Aerodynamic modelling is used to determine the optimum
tower height, control systems, number of blades and blade shape. Wind
turbines convert wind energy to electricity for distribution. Conventional
horizontal axis turbines can be divided into three components.
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2.3.2 WIND POWER PRODUCING CIRCUIT
Fig. 2.4 Wind power producing circuit
Differential heating of the earth’s surface and atmosphere induces
vertical and horizontal air currents that are affected by the earth’s rotation
and contours of the land and generates wind. A wind turbine obtains its
power input by converting the force of the wind into torque (turning
force) acting on the rotor blades. The amount of energy which the wind
transfers to the rotor depends on the density of the air, the rotor area, and
the wind speed. The dynamo fitted to the rotor converts the mechanical
energy to electrical energy, the produced electricity is used to recharge
the battery.
2.4 COMPONENTS USED
2.4.1 MILD STEEL SHEETS
Sheet metal is simply metal formed into thin and flat pieces. It is
one of the fundamental forms used in metalworking and can be cut and
bent into a variety of different shapes. Countless everyday objects are
constructed with sheet metal. Thicknesses can vary significantly;
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extremely thin thicknesses are considered foil or leaf, and pieces thicker
than 6 mm (0.25 in) are considered plate.
Sheet metal is available in flat pieces or as a coiled strip. The coils are
formed by running a continuous sheet of metal through a roll slitter.
The thickness of the sheet metal is commonly specified by a traditional,
non-linear measure known as its gauge.
Fig 2.5 Sheet metal
Forming process of sheet metal
Several forming process carried out by using sheet metals are,
i. Bending
Bending is a manufacturing process that produces a V-shape, U-
shape, or channel shape along a straight axis in ductile materials,
most commonly sheet metal. Commonly used equipment
includes box and pan brakes, brake presses, and other
specialized machine presses. Typical products that are made like
this are boxes such as electrical enclosures and rectangular
ductwork.
ii. Curling
Curling is a sheet metal forming process used to form the edges
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into a hollow ring. Curling can be performed to eliminate sharp
edges and increase the moment of inertia near the curled end. Other
parts are curled to perform their primary function, such as door
hinges.
iii. Decambering
Decambering is the metalworking process of removing camber, or
horizontal bend, from strip shaped materials. The material may be
finite length sections or continuous coils. Decambering resembles
flattening or levelling processes, but deforms the material edge
(left or right) instead of the face (up or down) of the strip.
iv. Perforating
Perforating is a cutting process that punches multiple small holes
close together in a flat work piece. Perforated sheet metal is used to
make a wide variety of surface cutting tools, such as the surform.
2.4.2 SOLAR PANEL
Fig.2.6 Solar panel
A solar panel is a set of solar photovoltaic modules electrically
connected and mounted on a supporting structure. A photovoltaic module
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is a packaged, connected assembly of solar cells. The solar panel can be
used as a component of a larger photovoltaic system to generate and
supply electricity in commercial and residential applications. Each
module is rated by its DC output power under standard test conditions
(STC), and typically ranges from 100 to 320 watts. The efficiency of a
module determines the area of a module given the same rated output - an
8% efficient 230 watt module will have twice the area of a 16% efficient
230 watt module. A single solar module can produce only a limited
amount of power; most installations contain multiple modules.
A photovoltaic system typically includes a panel or an array of solar
modules, an inverter, and sometimes a battery, solar tracker and
interconnection wiring.
Application of solar panels
i. Pumps
Solar well pumps are common and widespread. They often meet
a need for water beyond the reach of power lines, taking the place
of a windmill or wind pump. One common application is the filling
of livestock watering tanks, so that grazing cattle may drink.
Another is the refilling of drinking water storage tanks on remote
or self-sufficient homes.
ii. Fans
Connecting a photovoltaic panel directly to a DC mechanical
fan motor can provide air movement when it is most needed during
the day. Common applications include
both attic and greenhouse ventilation. Increased efficiency can be
obtained by interposing a linear current booster (LCB) between the
solar panel and the fan motor, to more closely coordinate varying
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panel output with motor energy requirements. Other controls
sometimes used are timers and thermostats, so that the fan does not
run when not wanted, even if the sun is shining.
iii. Solar vehicles
Ground, water, air or space vehicles may obtain some or all of
the energy required for their operation from the sun. Surface
vehicles generally require higher power levels than can be
sustained by a practically sized solar array, so a battery is used to
meet peak power demand, and the solar array recharges it. Space
vehicles have successfully used solar photovoltaic systems for
years of operation, eliminating the weight of fuel or primary
batteries.
iv. Small scale solar systems
Solar systems usually generate power amount of ~2 kW or less.
Through the internet, the community is now able to obtain plans to
construct the system and there is a growing trend toward building
them for domestic requirements. Small scale solar systems are now
also being used both in developed countries and in developing
countries, for residences and small businesses. One of the most
cost effective solar applications is a solar powered pump, as it is far
cheaper to purchase a solar panel than it is to run power lines.
2.4.3 RECIRCULATING PUMP
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Fig. 2.7 Recirculating pump
A circulator pump is a specific type of pump used to
circulate gases, liquids, or slurries in a closed circuit. They are commonly
found circulating water in a hydronic heating or cooling system. Because
they only circulate liquid within a closed circuit, they only need to
overcome the friction of a piping system (as opposed to lifting a fluid
from a point of lower potential energy to a point of higher potential
energy).
Circulator pumps as used in hydronic systems are usually electrically
powered centrifugal pumps. As used in homes, they are often small,
sealed, and rated at a fraction of a horsepower, but in commercial
applications they range in size up to many horsepower and the electric
motor is usually separated from the pump body by some form of
mechanical coupling. The sealed units used in home applications often
have the motor rotor, pump impeller, and support bearings combined and
sealed within the water circuit. This avoids one of the principal
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challenges faced by the larger, two-part pumps: maintaining a water-tight
seal at the point where the pump drive shaft enters the pump body.
Small- to medium-sized circulator pumps are usually supported entirely
by the pipe flanges that join them to the rest of the hydronic plumbing.
Large pumps are usually pad-mounted.
Pumps that are used solely for closed hydronic systems can be made
with cast iron components as the water in the loop will either become de-
oxygenated or be treated with chemicals to inhibit corrosion. But pumps
that have a steady stream of oxygenated, potable water flowing through
them must be made of more expensive materials such as bronze.
2.4.4 BLOWER FAN
Fig.2.8 Blower fan
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Blower fans are by far the most prevalent type of fan used in the air
conditioning industry today. They are usually cheaper than axial fans and
simpler in construction. It is used in transporting gas or materials and in
ventilation system for buildings. They are also used commonly in central
heating/cooling systems. They are also well-suited
for industrial processes and air pollution control systems. It has
a fan wheel composed of a number of fan blades, or ribs, mounted around
a hub. As shown in Figure 1, the hub turns on a driveshaft that passes
through the fan housing.
2.4.5 BATTERY
Fig.2.9 12V lead acid battery
An electric battery is a device consisting of one or
more electrochemical cells that convert stored chemical energy into
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electrical energy. Each cell contains a positive terminal, or cathode, and a
negative terminal, or anode. Electrolytes allow ions to move between the
electrodes and terminals, which allows current to flow out of the battery
to perform work. Primary (single-use or "disposable") batteries are used
once and discarded; the electrode materials are irreversibly changed
during discharge. Common examples are the alkaline battery used
for flashlights and a multitude of portable
devices. Secondary (rechargeable batteries) can be discharged and
recharged multiple times; the original composition of the electrodes can
be restored by reverse current. Examples include the lead-acid batteries
used in vehicles and lithium ion batteries used for portable electronics.
Batteries come in many shapes and sizes, from miniature cells used to
power hearing aids and wristwatches to battery banks the size of rooms
that provide standby power for telephone exchanges and computer data
centers. Batteries have much lower specific energy (energy per unit mass)
than common fuels such as gasoline. This is somewhat mitigated by the
fact that batteries deliver their energy as electricity (which can be
converted efficiently to mechanical work), whereas using fuels in engines
entails a low efficiency of conversion to work.
2.4.6 WIND TURBINE
A wind turbine is a device that converts kinetic energy from
the wind into electrical power. A wind turbine used for charging batteries
may be referred to as a wind charger. The result of over a millennium of
windmill development and modern engineering, today's wind turbines are
manufactured in a wide range of vertical and horizontal axis types. The
smallest turbines are used for applications such as battery charging for
auxiliary power for boats or caravans or to power traffic warning signs.
Slightly larger turbines can be used for making small contributions to a
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domestic power supply while selling unused power back to the utility
supplier via the electrical grid.
2.4.7 HEATING COIL
Fig.2.10 Heating coil
Water heating is a thermodynamic process that uses an energy
source to heat water above its initial temperature. Appliances that provide
a continual supply of hot water are called water heaters, hot water
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heaters, hot water tanks, boilers, heat exchangers, geysers, or calorifiers.
These names depend on region, and whether they heat potable or non-
potable water, are in domestic or industrial use, and their energy source.
In domestic installations, potable water heated for uses other than space
heating is also called domestic hot water.
3. MODEL AND CALCULATION
3.1 MODEL OF COOLER
Fig.3.1 Front view
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Fig.3.3 Back view
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Fig.3.4 Isometric view
Fig.3.5 Isometric view with water circuit
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Fig.3.6 Isometric view with heating coil
3.2 SOLAR PANEL SPECIFICATION
300mm
Fig 3.7 Solar panel specification
i. 300x300mm Photovoltaic panel
ii. 10 watts capacity
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300mm
iii. 12v DC
3.3 WIND TURBINE SPECIFICATION
Fig 3.8 Wind turbine specification
i. Length of blade=70mm
ii. Dynamo capacity=12v
3.4 CIRCUIT DIAGRAM
Fig 3.9 Circuit diagram
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3.4.1 SOLAR POWER CIRCUIT
i. Before starting the operation, the solar panel is exposed to sun rays.
ii. The solar panel converts the solar energy into 12VDC electrical
energy.
iii. This electrical energy from the solar panel is utilized to run the set
up of cooler.
3.4.2 WIND POWER CIRCUIT
i. The outside temperature of the cooler is reduced to lower level and
the cooling effect is achieved by the supplying air mist from the
cooler forced from the fan blower.
ii. The sprayed water is collected in a sump at the bottom of the
cooler unit.
3.5 EVAPORATIVE COOLER CALCULATION
Dry bulb temperature ( chennai )=40o c =104oF
Wet bulb temperature=25oC=77oF
Efficiency of media in direct cooling method= 90%
Efficiency of media in indirect cooling method=70%
Temperature reduction achievable using direct evaporative cooling
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=(dry bulb temp-wet bulb temp) x media efficiency
=(104-77) x 0.9
= 24.3oF
Achievable temperature= dry bulb temp- achievable temp drop
=104-24.3
=79.7oF = 26.5oC
Saturation efficiency
Saturation efficiency = Ti-To
Ti-Two
= 104-79.9
104-77
= 0.9
= 90%
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Air flow velocity =500 fpm = 2.54 m/s
Building volume =10x8x8 = 640 cubic ft.
Air change = 30 corresponding to79.7oF
Evaporative cooling in Standard Cubic Feet per Meter (SCFM)
SCFM = 640 cubic ft/ Ac x 30 AC / liters / 60 min
SCFM = 640x30
60
= 320 SCFM
Evaporation rate = SCFM x wet bulb depression x sat
8700
= 320x24.3x0.9
8700
Evaporation rate = 8 GpH = 0.61 liters /min
3.6 POWER AND TIMECALCULATIONS
3.6.1 SOLAR PANEL CALCULATION
For 17 AH, 12V battery watt hour
17x12= 204 WH
For a panel having low power producing capacity, the net power
produced is given.
Calculated with loss factor.
10x0.85=8.5W
Hence to obtain 204 WH = time x 8.5
Time = 24 hours
Thus the battery need to be charged for 24 hours by the solar panel for
complete charging of battery.
3.6.2 WIND POWER CALCULATION
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Length of blade = 0.07m = radius of blade
Wind speed V = 12m/s
Density of air r = 1.23 kg/m3
Betz limit Cp = 0.4
Area A = pr2
= px0.072
A = 0.0154m2
Power available = 1x r.A.V3xCp
2 = 1x1.23x0.0154x123x0.4
2
P = 6.546 W
Hence the time taken for recharging the battery is
204 WH= Time x 6.546
Hence Time = 31.16 hrs
3.6.3 COMBINED TIME CALCULATION
Net power produced by solar panel= 8.5 W
Net power produced by wind turbine=6.546W
Hence the time taken for recharging the battery with the help of combined
power is given by
204WH = Time x ( 8.5 + 6.546 )
Time = 13.55 hours
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3.7 TIME GRAPH
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8 9 10 11 120
20
40
60
80
100
120
Fig 3.10 Wind speed vs Time taken for rechargingWind speed in m/s
Tim
e in
hrs
3.8 COMBINED TIME GRAPH
8 9 10 11 120
5
10
15
20
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Fig.3.11 Varying wind speed with constant solar power 10WWind speed in m/s
Tim
e in
hrs
6 7 8 9 100
5
10
15
20
25
30
Fig.3.12 Varying Solar power with constant wind speed 9m/sPower in watts
Tim
e in
hrs
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4. FABRICATION AND RESULT
4.1 CONSTRUCTION OF EVAPORATIVE COOLER
It consists of a box shaped hollow structure to a size of 450 x 450 x
450 mm. It is made of M.S. sheet of thickness of 1.5mm. The top and
bottom of the cooler is designed as the shape of a dome for easy flow of
air and water. The sprayer arrangement is provided on the top of the
cooler. The water to be spray is pumped from the sump in the cooler and
passed through the plastic pipes which has the holes for spraying the
water sprayed.
The blower is fitted at the side of the cooler. The wire meshes are
provided to slow down the flow of both air and water and to provide more
time of contact. The air from the blower passes through the water spray
and gets cooled. This cooled air is passed through the ventilator. At same
procedure it will be operated as warmer with the help of heating coil
provided in sump. Heating coils temperature can be adjust.
An electrical switch panel board is mounted outside the cabin to
switch ON / OFF the fan unit. The whole arrangement is coated with
metal primer and then finishes with decorative metal enamel paint. The
solar panel is 150 x 600 mm size producing the 12V DC supply when the
sun rays are falls on it. And the wind turbine is producing 12V DC
whenever the energy available in atmosphere which tend to rotate wind
turbine blades. And it will produce the required electricity for the system.
4.1.1 STAGES OF FABRICATION
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Fig 4.1 Fabrication of cooler box
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4.2 WORKING PRINCIPLE
There are three circuits and one control panel involved,
1. Water circuit
2. Air circuit
3. solar panel circuit
4. Electrical control panel.
i. Electrical control panel
There are three switches used to control this unit. First
switch is used for ON/OFF control. The second one is used for
switching either pump or heater unit. The third switch is used for
forward and reverse control of blower fan.
ii. Water circuit
The water from the cooler sump is discharged at the top of
the cooler. The water is sprayed through the holes provided in the
plastic pipes. The water enters the pipe and passes out through the
row of holes in the pipe in order to have more contact with the air
by spraying the water.
iii. Air circuit
The outside temperature of the cooler is reduced to lower
level and the cooling effect is achieved by the supplying air mist
from the cooler forced from the fan blower. The sprayed water is
collected in a sump at the bottom of the cooler unit.
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iv. Solar panel and wind turbine circuit
Before starting the operation, the solar panel is exposed to
sun rays. The solar panel converts the solar energy into 12VDC
electrical energy. This electrical energy from the solar panel is
utilized to run the pump.
Whenever the moisture is exposed air either in the form of
droplets (or) sheet, part of it is evaporated. As the liquid changes
into vapour, the heat required for evaporation is taken from the
remaining water itself and thus the water gets cooled.
Whenever the water comes in contact with the atmospheric
air, the heat from the air to water is also transferred as “sensible
heat” as the hot air temperature is higher than the cold water
temperature. i.e wet temperature is lower than dry bulb
temperature. The heat transfer due to evaporation increases, as
WBT of atmosphere air is lower than DBT of air. The difference
between the DBT and WBT indicates the capacity of air to absorbs
the water vapor. The rate of heat transfer between the water and
air depends upon
1. The initial temperature of water
2. Temperature of atmospheric air,
3. Relative humidity of air,
4. The movement of air and solar radiates
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5. Higher DBT
6. Lower WBT
7. Higher air movement gives the better cooling of water
8. Area of heat transfer
9. Duration of contact between the two medicines
The net heat rejected per kg of air from the water is given by
80% of total total gain by water is removed by evaporation and 20% by
sensible heat transfer.
Total heat transferred = heat of evaporation + sensible heat
The rate of evaporation of water in cooling tower and subsequent
reduction in water temperature depends upon the following factors,
a. Amount of water surface exposed
b. The time of exposure
c. The relative velocity of air passing over the water droplets
formed in Cooler.
d. The R.H. of air and difference between the inlet air WBT
and water
e. Inlet temperature
f. The direction of air flow relative to water
Higher the surface area, more time of exposure, low relative
humidity, higher difference between WBT of air and water inlet
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temperature and cross flow lead to effective cooling and reduce the tower
size.
4.3 ADVANTAGES OF HYBRID AIR COOLER AND WARMER
i. Does not depends upon any conventional power source and hence
can be operated any time irrespective of the power-cut.
ii. Since it is a hybrid system, the battery can be re-charged under any
climatic conditions
iii. It can be used in any climatic condition for air conditioning
iv. Less maintenance required
v. Portable system
vi. Easy to operate
vii. The efficiency of the system increases as the atmospheric
temperature increases, hence it performs well in warmer countries
like India.
4.4 LIMITATIONS
i. Depends upon nature’s mercy
ii. Reflection losses at the top surface of solar panel
iii. Incomplete absorption of the photon energy due to limited cell
thickness
iv. Frictional loss in wind energy rotor
v. Battery life
vi. Varying power input to battery
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4.5 COST ESTIMATION
Table 4.1 Cost estimation
S.NO COMPONENTS COST (Rs)
1 SOLAR PANEL 2300
2 BLOWER FAN 1600
3 WIND TURBINE 700
4 WATER PUMP 1200
5 SHEET METAL 1300
6 WATER CONTAINER 300
7 PIPE LINE 100
8 PAINT 200
9 BATTERY 1200
10 HEATING COIL 400
11 CONNECTING WIRE 100
12 WELDING 800
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TOTAL Rs.10200
5. CONCLUSION
Our project may be right solution for renewable energy utilization
which is the future. Efficiency of renewable energy utilization is
improved by combining solar and wind energy in our project. In future
the demand for our project rises automatically due to the lack of non-
renewable energy resource and increasing global warming. Since it can
be used as warmer as well, it can be used in any climatic conditions.
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REFERENCE
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