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#BirhanNega ኦንላይን ቢዝነስ ምንድነው? ገንዘብ ማግኘት የምንችልባቸው መንገዶች

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EXHAUST GAS RECIRCULATION (EGR) SYSTEM: WORKING PRINCIPLE, DESIGN, AND BENEFITS

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Diesel engines tend to emit higher Nitrogen Oxide (NOx) which is harmful to humans. This is because of the high temperatures in the engine cylinders because of the higher compression ratio. To control and decrease the NOx, manufacturers employ 'Exhaust Gas Recirculation' technology in engines. The term EGR stands for Exhaust Gas Recirculation. It is a part of modern-day diesel engine vehicles which helps to decrease the Nitrogen Oxide (NOx) emissions. Exhaust Gas Recirculation is the technique used for reducing the nitrogen oxide in both the internal combustion diesel engines as well as petrol engines. Exhaust gas recirculation (EGR) is the most common technology to reduce nitrogen oxides (NOx) emissions on diesel internal combustion engines (ICE). EGR takes exhaust gases from the exhaust manifold and reintroduces them into the intake manifold, mixing them with fresh air. By doing this, the main ingredients of NOx emissions are reduced: * oxygen: which is displaced by i...

INJECTION SYSTEM: COMPONENTS, TYPES AND WORKING PRINCIPLES

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Fuel injection is the introduction of fuel in an internal combustion engine, most commonly automotive engines, by the means of an injector. The fuel injection system lies at the very heart of the diesel engine. By pressurizing and injecting the fuel, the system forces it into air that has been compressed to high pressure in the combustion chamber. Fuel injector is an electronically controlled mechanical device that is responsible for spraying (injecting) the right amount of fuel into the engine so that a suitable air/fuel mixture is created for optimal combustion. The electronic control unit (ECU at engine management system) determines the precise amount and specific timing of required gasoline (petrol) dose for every cycle, by collecting information from various engine sensors. So, the ECU sends a command electrical signal of the correct duration and timing to the fuel injector coil. In that way opens the injector and allows petrol to pass through it into the engine. T...

ENGINE COOLING SYSTEM: COMPONENTS, TYPES AND WORKING PRINCIPLES

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A vehicle’s engine-cooling system serves not just to keep the engine cool, but to also keep its temperature warm enough to ensure efficient, clean operation. System components include a radiator to dissipate heat, a fan or fans to ensure adequate airflow for radiator cooling, a thermostat valve that opens when the desired operating temperature is reached and a water pump (or coolant pump) to circulate coolant through the engine, hoses and other components. Most vehicles now employ an expansion tank that allows the coolant to expand, and exit, the cooling circuit when hot, and to return when the car is turned off and the engine cools. The cooling system also incorporates elements of the cabin’s ventilation system, because engine heat is used to warm the car’s interior. While running, an engine continuously produces heat and converts it into power. This heat is derived by burning fuel in the engine. But as we all know, there is no engine in the world which is 100% efficient. Ther...

ELECTRIC VEHICLES: COMPONENTS AND WORKING PRINCIPLE

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All-electric vehicles (EVs) have an electric motor instead of an internal combustion engine. The vehicle uses a large traction battery pack to power the electric motor and must be plugged into a charging station or wall outlet to charge. Because it runs on electricity, the vehicle emits no exhaust from a tailpipe and does not contain the typical liquid fuel components, such as a fuel pump, fuel line, or fuel tank. All-electric vehicles (EVs) use a battery pack to store the electrical energy that powers the motor. EVs are sometimes referred to as battery electric vehicles (BEVs). EV batteries are charged by plugging the vehicle into an electric power source. Although electricity production may contribute to air pollution, the U.S. Environmental Protection Agency categorizes all-electric vehicles as zero-emission vehicles because they produce no direct exhaust or emissions. Both heavy-duty and light-duty EVs are commercially available. EVs are typically more expensive than similar ...