Air Pollution done by IC Engines and Its Control

I.C engines convert heat energy into mechanical energy by burning the fuel in its combustion chamber called cylinder. Mostly, petrol and diesel oil are used as fuels for I.C engines. These fuels contain Hydrogen and Carbon in Various Combinations. During Combustion, Oxygen Combines with Hydrogen and Carbon to form water (H20), Carbon Monoxide (CO) and Carbon dioxide (Co2). The Nitrogen in the fuel combines with oxygen and forms Nitrogen oxide ( No2). Remaining fuel goes unburnt resulting in smoke and ash. Exhaust gas constituents consist of partly burned petrol, carbon monoxide , nitrogen oxides and if Sulphur in petrol, Sulphur oxides, Pollute the air.

The oxides of Nitrogen together with hydrocarbons react in the presence of sunlight and form petrochemical smog. As a result, smog is created, the atmosphere becomes dirty and breathing becomes difficult. Its bad effect includes crop damage, eye irritation, objectionable odor, decrease of visibility, cracking in rubber etc.

Smog is a kind of fog mixed with other substances. The smog covers the cities like a blanket for days together during winter. The heat generated in large cities tends to circulate air within a dome - like shape. Smog among with smoke is the most visible evidence of air pollution.

Some of the atmospheric pollutants are not visible until mixed with moisture. Unburnt petrol, carbon monoxide, leaded compounds from leaded petrol , carbon monoxide , leaded compounds from leaded petrol and other gases which pollute the air, may not be seen. All these pollutants are deadly harmful for men, animals and food crops.

Men inhale nearly 15kg of air per day. If these pollutants are added to the air, it gives harmful effects to men such as asthma , eczema , emphysema , cardiovascular troubles, lung and stomach cancer.

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ELECTRICAL COMPARATORS AND ITS WORKING

Electrical Comparators are used as a means of detecting and amplifying small movements of a work contacting elements. An electrical comparator consists essentially of a pick-up head or transducer for converting a displacement into a corresponding change in current and a meter or recorder connected in the circuit to indicate the electrical change, calibrated to show in terms of displacement. Generally, an amplifier is needed to provide the requisite sensitivity and to match the characteristics of different parts of the circuit. Electrical comparators can be classified according to the electrical principle used in the pick-up head. Most of the comparators use either a differential transformer, an inductance bridge, a strain gauge or a capacitor as a means of detecting movement of the gauging element. There are different types of electrical comparators. One kind called an electrolimit gauge is used to check or measure the outside diameter of a roll. The object to be checked is place

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Advantages And Disadvantages Of Air Refrigeration System :

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Mechinopedia For Mechanical Engineers

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