FABRICATION AND ANALYSIS OF MIST FAN CHAPTER-1 INTRODUCTION Misting systems work by forcing water via a high pressure pump and tubing through a brass and stainless steel mist nozzle that has an orifice of about 5 micrometers, thereby producing a micro- fine mist. The water droplets that create the mist are so small that they instantly flash Evaporate. Flash evaporation can reduce the surrounding air temperature by as much as 35 °F (20 °C) in just seconds. For patio systems, it is ideal to mount the mist line approximately 8 to 10 feet (2.4 to 3.0 m) above the ground for optimum cooling. Misting is used for applications such as flowerbeds, pets, livestock, kennels, insect control, odor control, zoos, veterinary clinics, cooling of produce, and greenhouses. 1.1 MIST FAN: On a hot summer's day, a misting fan can be your best friend. It works on the same principle of a humidifier. A fan blows a fine mist of water into the air and if the air isn't humid, the mist evaporates, taking heat from the air with it. This allows the misting fan to work like an air cooler. In a dry climate, a misting fan can work very well outdoor. Misting fans come in many different styles, from industrial strength, to small portable battery-operated fans that consist of an electric fan and a hand-operated water spray pump. You will want a larger NRCM,Department of Mechanical Engineering 1
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FABRICATION AND ANALYSIS OF MIST FAN
CHAPTER-1INTRODUCTION
Misting systems work by forcing water via a high pressure pump and tubing through a brass
and stainless steel mist nozzle that has an orifice of about 5 micrometers, thereby producing a
micro-fine mist. The water droplets that create the mist are so small that they instantly flash
Evaporate. Flash evaporation can reduce the surrounding air temperature by as much as 35 °F
(20 °C) in just seconds. For patio systems, it is ideal to mount the mist line approximately 8 to 10
feet (2.4 to 3.0 m) above the ground for optimum cooling. Misting is used for applications such
On a hot summer's day, a misting fan can be your best friend. It works on the same principle
of a humidifier. A fan blows a fine mist of water into the air and if the air isn't humid,
the mist evaporates, taking heat from the air with it. This allows the misting fan to work like an
air cooler. In a dry climate, a misting fan can work very well outdoor. Misting fans come in
many different styles, from industrial strength, to small portable battery-operated fans that
consist of an electric fan and a hand-operated water spray pump. You will want a larger model to
get any sort of benefit. They use the cooling power of evaporating water, so they are all natural
and good for the environment.
Use of misting fan
At home: Of course this is the logical choice. Think of how nice it will be to have a misting
fan at home, helping you cool when the weather begins to heat up. With it forecasted to be the
hottest summer on record this year, having a misting fan can be a cheap alternative to an air
conditioner, especially in terms of the energy being used.
Festivals: If you are hosting a festival, you want people to be comfortable. Well-placed misting fans on a hot summer day can become the most popular attraction of the festival, and there may be line-ups to enjoy them.
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FABRICATION AND ANALYSIS OF MIST FAN
Sports: Any time you have outdoor sports, you have people sitting for long periods of time watching. Having a misting fan on-hand can help keep them cool, and help protect them from the dangers of heat stroke and dehydration
Pool Parties: While being in the pool is great to cool off; sometimes sitting by the pool is nice. To make the experience even nicer, you can have a misting fan set up so that your guests who aren’t in the pool, are still enjoying the cooling feeling of water on their bodies.
Benefits
The heat is not just uncomfortable, it is downright dangerous. In 2003, Europe had its hottest summer since 1540. During that summer, when temperatures reached record levels, 70,000 people died from the heat. In France, they had seven days of 40ºC temperature, something never seen there, resulting in 14,000 deaths.
Having a convenient way to cool is important. Humans sweat, and that sweat forms beads on our skin. When a breeze passes over that, it cools the water and helps us cool down. This is why something like a misting fan can be so important. It creates beads of cool water in the air, which falls on those around it, helping keep them cool without having to use the energy of an air conditioner. So, who can benefit from having a misting fan?
Children: Protecting your children is important and when they are playing outside, having a misting fan will keep them cool when the temperature begins to rise. Sometimes children forget to get something to drink when they are having fun, and that can lead to health problems such as dehydration. To prevent that from happening, have them play near a misting fan, so they can keep cool and hydrated while they play.
Pets: Your pets don’t sweat like you do. For example, dogs burn heat off their bodies by panting, or through their paws. This is why it is important that you have a misting fan set up for your outside pets, along with water bowls and shade. That way, they can keep cool and comfortable, and you won’t have to worry about.
Them becoming ill or even dying from the heat. The same goes for horses. While horses do sweat, you can have a misting fan set up in the horse stables so that while your horses are resting, they are keeping cool.
Workers: If you have employees outside, or in a warehouse where the temperature can get high, having a misting fan will protect those people. It also keeps workers comfortable. A comfortable person is a person who is productive. Any time workers are battling the heat, they are not doing their job at full capacity, and that is going to cost additional money.
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FABRICATION AND ANALYSIS OF MIST FAN
BASIC PRINCIPLE:
Misting fan reduces the temperature of air using the principle of evaporative cooling,
unlike typical air conditioning systems which use vapor-compression refrigeration or
absorption refrigerator. It is the addition of water vapor into air, which causes a lowering of
the temperature of the air. The other principle of this system is that the cold water flows into
the environment that absorbs the heat from the hot air and it maintain the cool temperature as
compare to other place.
CHAPTER-2
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FABRICATION AND ANALYSIS OF MIST FAN
LITERATURE REVIEW
Misting systems work by forcing water via a high pressure pump and tubing through a brass and stainless steel mist nozzle that has an orifice of about 5 micrometres, thereby producing a micro-fine mist. The water droplets that create the mist are so small that they instantly flash evaporate. Flash evaporation can reduce the surrounding air temperature by as much as 35 °F (20 °C) in just seconds. For patio systems, it is ideal to mount the mist line approximately 8 to 10 feet (2.4 to 3.0 m) above the ground for optimum cooling. Misting is used for applications such as flowerbeds, pets, livestock, kennels, insect control, odor control, zoos, veterinary clinics, cooling of produce, and greenhouses.
Evaporative coolers lower the temperature of air using the principle of evaporative cooling, unlike typical air conditioning systems which use vapor-compression refrigeration or absorption refrigerator. Evaporative cooling is the addition of water vapor 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, the energy present in the water vapor component of the air, whilst the air remains at a constant enthalpy value. 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. Evaporative cooling can be visualized using a psychrometric chart by finding the initial air condition and moving along a line of constant enthalpy toward a state of higher humidity.
A simple example of natural evaporative cooling is perspiration, or sweat, secreted by the body, evaporation of which cools the body. The amount of heat transfer depends on the evaporation rate, however for each kilogram of water vaporized 2,257 kJ of energy (about 890 BTU per pound of pure water, at 95 °F (35 °C)) are transferred. The evaporation rate depends on the temperature and humidity of the air, which is why sweat accumulates more on humid days, as it does not evaporate fast enough.
The term bacteria as used herein, is a chemical agent which prevents multiplication of bacteria. Evaporative coolers have heretofore employed hygroscopic evaporative cooler pads such as those made of wood excelsior and have utilized recirculating pumps to pump water drained from the pads back to an elevated position at the upper portions of the pad so that water 'is continuously used. In such evaporative coolers, bacteria tends to grow during warm weather and create serious problems. One unpleasant conditon arises when the bacteria multiplies to such an extent that the cool air is laden with bacteria and unpleasant due to the odor of the bacteria. Accordingly, it is an object of the invention to provide a bacteria proof evaporative cooler having hygroscopic pads which are treated with a bacteriostat which prevents the multiplication of bacteria in an evaporative cooler.
Another object of the invention is to provide an evaporative cooler wherein the evaporative cooler pads are treated with a bacteriostat and operated at a relative humidity of 75 percent or greater, thereby causing the bacteriostat to become sufficiently active to kill bacteria. Understanding evaporative cooling performance requires an understanding of psychrometrics. Evaporative cooling performance is variable due to changes in external temperature and humidity level. A residential cooler should be able to decrease the temperature of air by 3 to 4 °C(or in Fahrenheit scale by 5 to 7 °F).
It is simple to predict cooler performance from standard weather report information. Because weather reports usually contain the dewpoint and relative humidity, but not the wet-bulb temperature, a psychrometric chart or a simple computer program must be used to compute the wet bulb temperature. Once the wet bulb temperature and the dry bulb temperature are identified, the cooling performance or leaving air temperature of the cooler may be determined. For direct evaporative cooling, the direct saturation efficiency, measures in what extent the temperature of the air leaving the direct evaporative cooler is close to the wet-bulb temperature of the entering air.
A nozzle is a device designed to control the direction or characteristics of a fluid flow (especially to increase velocity) as it exits (or enters) an enclosed chamber or pipe. A nozzle is often a pipe or tube of varying cross sectional area, and it can be used to direct or modify the flow of a fluid (liquid or gas). Nozzles are frequently used to control the rate of flow, speed, direction, mass, shape, and/or the pressure of the stream that emerges from them. In a nozzle, the velocity of fluid increases at the expense of its pressure energy.