This document describes the design and analysis of a hybrid cooler. It discusses the principles of evaporative cooling and how desert coolers work by blowing dry, hot air over a wet surface, which cools the air through evaporation. The methodology section outlines the development of a mathematical model, fabrication of the proposed design, experimental validation, and measurement of coefficient of performance. The expected outcomes are a new hybrid cooler design that provides both air conditioning and water cooling using evaporation, serving as an environmentally friendly alternative to air conditioners. Key components of the design include cooling pads, fans, pumps, and stainless steel sheets. References are provided on previous research conducted on evaporative cooling and desert cooler performance.

1. DESIGN AND ANALYSIS OF A
HYBRID COOLER
Guided By. Submitted By
Vikas Sahu
Prof. Harsh Jain

2. PRINCIPLE OF DESERT COOLER
 Desert coolers are based on the simple principle that when
unsaturated air comes in contact with water, the water
evaporates. In the process, the moisture content of air
increases, while its temperature decreases. The resulting cold
but moist air is used for providing cooling . Thus a desert
cooler is a simple device, which consists of an arrangement for
blowing dry and hot air over a wet surface and arrangement for
keeping the surface wet continuously. The cooler normally
consist of a blower and a pump.

3. Evaporative cooling
Evaporative cooling is a process that reduces the temperature of air
by the evaporation of water into the air-stream. As water is
evaporated the latent heat of vaporization is taken either by air, water
or both air and water, results in cooling of air and water.
(Direct evaporative cooling) (Indirect evaporative cooling.)

4. PRINCIPLE OF DESERT COOLER
Desert cooler

5. METHODOLOGY
 Mathematical model.
 Fabrication of proposed design.
 Experimental validation of proposed mathematical model.
 Coefficient of performance(C.O.P) of proposed cooler.

6. EXPECTED OUTCOME
 A new design of desert cooler utilized for water cooling as well
as air conditioning, is being proposed which would be very
useful especially for hot and composite climates like Raipur
(CG).
 A substitute for CFC based air conditioners and refrigerators,
this device is based on principle of evaporation would be
environment friendly and will consume negligible amount of
electricity.
 It would be a cost effective and innovative design.

7. PARTS / EQUIPMENTS/DEVICE NEEDED
Cooling Pad - Cellulose cooling pad for more efficiency and greatest
performance during summer seasons. Eco Cool Evaporative Cooling Pads
that were manufactured using special cellulose material. Top quality
material is useful in achieving high cooling efficiency and ensuring
degradation resistance. The pads are known for their exceptional wetting
properties and airflow to achieve maximum.

8. Fan-Air cooling systems in Cooler most commonly rely
on forced air. Forced air is passed through cooling
elements and circulated to the desired locations. Blower
provides this air movement.

9. Pump- Circulating pump draws water from the basin under the
pumps it through a system of sprays (or water distributors) from
which the water is directed onto the tube surfaces. Air is induced or
forced over the wetted tube surfaces and through the rain of water
droplets.

10. Stainless steel metal sheet – We are using stainless steel metal sheet for
making body of cooler. Metal sheet upto width of 5mm.

11. LITREATURE
The use of direct evaporative coolers (commonly known as desert
coolers) is very widespread in the third world countries, during hot
and dry weather. It consists of a cubical box of sheet metal or plastic
containing large vertical filter (Pads) an electric motor driven fan, a
water pump, a water distribution system, and a water sump (tank) at
the bottom, Fan draws in warm air from outside through wetted
media, air gets evaporated and thus cooled. The water pump lifts the
water from the sump through distribution system to the top of the
pads from where it trickles down by gravity back to water tank. The
cooled air is then delivered either directly into a room or into duct
distribution system, this is called as “Direct evaporative cooling” in
which the air comes in direct contact of water, the cooled and
humidified outside air flows to the room and removes heat.

12. Ideally, when water temperature is assumed to be at wet bulb temperature
of ambient air, the temperature of water remains constant neither raised nor
lowered evaporation results in cooling of air alone. But in desert coolers the
temperature of circulating water is considerably warmer than the wet bulb
temperature of air both air and water gets cooled. The process resembles in
cooling tower to cool warm water by evaporation.
It is suggested that in addition to cooling air, one can utilize the coolness
stored in the bottom tray (or tank) for medium temperature cooling; as an
example one can place a box in the tank to keep food cool or exchange heat with
the help of a coil placed in the tank or conditioned (cooled) tank water can be
utilized to enhance the distillate output of solar still. The present work explores
this option and in the process makes further progress in modelling of such
coolers, in particular by inclusion of the variation of the temperature of flowing
water along the direction of flow; the expressions for the corresponding
parameters also become different.

13. The present knowledge of evaporative cooling is based on theoretical and
experimental work on heat and mass transfer in wet porous pads with cross
flow of air and water and performance of devices based on evaporative
cooling, previous work limits up to the modeling based on the exit air
temperature, effectiveness and efficiency of desert cooler
All previous analysis discussed, correspond to the steady state and
neglect the variation of the temperature of water along the direction of flow; the
temperature of water has been assumed to be the wet bulb temperature,
throughout the pad. Unlike previous research works in this chapter the variation
of the temperature of water along the direction of flow has been taken into
account. The time variation of the temperature of water in the tank has also
been investigated. The effect of addition of heat to the water in the bottom tank
(for purpose of cooling) has also been studied. An expression for the average
temperature of cool air, flowing out of the pad has also been derived .The
theoretical results have been compared with the results of experiments
conducted by the authors. To validate mathematical model theoretical and
experimental time variation of tank water temperature is plotted.

14. REFRENCES
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17. THANK YOU