This chapter includes general information related to the main subject of this project which is a fogging system.
How does the system work?
The working principle of the fog cooling system can be summarized as this system utilizes very high pressure water about 1000 psi or 70 pars which occurred from a pump with high quality and delivery lines to create a very fine droplets size nearly 10 micron from specifically designed nozzles. Then, these fine droplets are quickly evaporated and absorbed the heat found in the air. In order to offer an excellent cooling; fog cooling systems use something called flash evaporation (Giacomelli, 2003).
Fog Evaporative cooling
According to Al-Amri, (2000) evaporative cooling is the chill that the person feels when his skin stroked by a breeze. With the energy of the human body, the water on the skin will be evaporated by the air. By using high-pressure pumps, the water will be forced through the misting nozzles creating tiny water droplets with less than ten microns size. The created water droplets will then absorb the heat (energy) that is existed in the environment quickly and evaporate to become a gas or water vapor. The used heat or energy to change the water from the liquid phase into gas is subtracted from the environment, and then the air will be cooled (Gupta et al., 1995).
Figure 1: fog cooling system (http://www.needeelee.com/about.htm)
Relative humidity
Relative humidity is the moisture amount in the air that is compared with the moisture amount that is can be absorbed by the air at nearly the same temperature, and it considered as a fundamental factor in the determination of cooling potential. The relative humidity with the amount of evaporated water and removed heat ...
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...nto micro-fine droplets that not exceeding 10 microns in size. The size of the droplet is the most significant factor that is controlling the performance of fog systems (Homji and Mee, 2002).
Air-cooled heat exchanger cooling technology
Fog systems can be applied also for cooling heat exchangers with large boosting, air-cooled compressor, and any additional processes that could take advantage from evaporative cooling with large-scale (Smithco, 2005).
Fire Fighting Fogging and mist Systems
Water fogging and mist systems are suitable for fighting various types of fires. It provided with sensors that works only when the temperature of the room is exceeding the natural levels, where these sensors release the water droplets or fogs in the air at high velocity which cools the surrounding area effectively and hence minimize the expected heat related damage (Bre, 2005).
Evaporation happens when a heat source beats down on water and turns the water into water vapor. The water rises up and goes into the clouds and then comes out when it rains. Then the cycle starts over again. Water evaporates when liquid turns into a gas for heat or other purposes. Silver nitrate is the chemical compound with the chemical formula agNO3. Silver nitrate was sometimes used in hospitals to prevent blindness in babies. Silver nitrate can also be used to detect any salt in water.
Most of the chillers works on vapor compression refrigeration cycle this can be replaced by Solar vapor absorption chillers which might results in many advantages over vapor compression chillers such as reduction in overall electrical cost, low noise operation, reduce operation cost, low co2 emission .
The current main issues concerning the next purchasing contracts for Marconil are that it is an input material on which we are very dependent and that if a shortage takes place, it can bring serious risks for our business in terms of reputation, sales revenues and customer loyalty. Last year, Sabor’s sales for air filtration systems accounted for $72 million dollars. With a profit margin of 72% (the manufacturing cost is 28%), Marconil enjoys a considerable importance in
Norbert Rillieux invented the triple effect vacuum evaporator. The "triple effect" is for the multiple things that the system does all at the same time. The "vacuum" is for the vacuum of air that is used in the system, and the "evaporator" is for the sugarcane liquid syrup that is heated and evaporated into regular sugar. The actual system is somewhat complicated, so please see the picture that is provided.
Refrigeration Refrigeration is defined as “The process of removing heat from an enclosed space, or from a substance, to lower its pressure.” (First website given in bibliography) In simpler terms, it is removing heat from states of matter in order to keep them cooler. The basic need for refrigeration is to cool food and beverages, as they often get spoilt if the temperature is high. Before actual refrigerators and other such mechanical systems were introduced, it was very common for people to cool their food with ice and snow.
... boost the air pressure by compression and high pressure air goes through the Secondary heat exchanger for further cooling using ram air.
A diffuser is a mechanical device that is designed to control the character of fluid at the entrance of a thermodynamic open system. It could be in the shape of round, rectangular and square. Diffusers are commonly used in heating, ventilation, and air-conditioning systems as a part of room air distribution subsystem, and serve several purposes as following, to deliver conditioned and ventilated air evenly, to distribute the flow of air in the desired directions, to create low velocity air movement in the occupied room and to enhance mixing of room air into the primary air being discharged (Eugene et al., 2011).
“It is heat carrying medium which absorb heat from space and reject heat to outside the refrigerator.” A simple vapor compression refrigeration system consists of the following equipments: Compressor
After the condensation process is finished and the steam reverts back to water, it is pumped into the reactor again, thus completing the process of producing nuclear-based power. Next, hydro-electricity is electricity produced by moving water, flowing past a turbine connected to a generator (“Hydropower”). According to Nationalgeographic.com, a typical hydro-plant is a system with three parts: an electric plant where electricity is produced, a dam that can be opened or closed to control water flow, and a reservoir where water can be stored.... ... middle of paper ... ...
The heat produced in the condenser tubes when the refrigerant condenses into a liquid is taken up by the cooling water, which is then sent out to a cooling tower or geothermal facility depending on the requirement.
... temperature of 112 0C also and a pressure 2.5 bar. Cooling water is used to condense the vapor exiting column. Remaining methane and hydrogen are separated in reflux drum where the vapor stream is combined with other gases streams. The overhead of first and second separator are combined to form fuel gas. The liquid stream exiting in the bottoms of the reflux drum is pumped at pressure of 3.3 bar for discharging pressure. The pump stream is separated in two streams. One stream is to feed to tray one of the column and the other one stream is cooled down to 38 0C in heat exchanger. Then, the cooled product stream is sent to storage.
Another system is called the spray dry system. A slurry of alkali is njected into the flue gases. The heat in the flue gases causes water to evaporate. The sulfur dioxide reacts with the drying alkali solution to form a solidi reaction product. There is no waste water from this process.
Heat transfer fluids used as industrial coolants for gas compressors, heating, ventilating, and air-conditioning systems, and ice skating rinks.
In thermodynamics Refrigeration is the major application area, in which the heat is transferred from a lower temperature region to a higher temperature region. The devices which produce refrigeration are known as Refrigerators and the cycle on which it operates are called refrigeration cycles. Vapour compression refrigeration cycle is the most regularly used refrigeration cycle in which the refrigerant is alternately vaporized and condensed and in the vapor phase it is compressed. Gas refrigeration cycle is the well-known refrigeration cycle in which cycle refrigerant remains in the gaseous phase throughout the cycle. Cascade refrigeration are the other refrigeration cycles discussed in this chapter; absorption refrigeration is the one more refrigeration cycle which is used where the refrigerant is dissolved in liquid before it is compressed. One more refrigeration in which refrigeration is produced by passing the electric current through two dissimilar materials is called as the thermoelectric refrigeration.
where σ is particle radius, Kp is thermal conductivity of particle, N is number density of the dust phase, τv is the relaxation time of the of dust phase that express the time required by the particle cloud (dust) to reduce its velocity relative to the fluid, and τT is the thermal equilibrium time that express the time required by the particle cloud to reduce its temperature relative to the