What is the function of EGR valve?
EGR means Exhaust Gas Recirculation. The main function of EGR is to control NOx emission from the engine. At elevated temperature (during long run & full condition)if due to some reasons engine gets heated up beyond certain level… it produces NOx emission. In order to avoid this pollution , we have to control the temperature rise inside the cylinder. This can be achieved by mixing some amount of exhaust gas with intake air. By doing this the temperature inside the combustion chamber is reduced. And NOx is controlled.
What is the difference between Critical speed & Whirling speed?
In Solid mechanics, in the field of rotor dynamics, the critical speed is the theoretical angular velocity which excites the natural frequency of a rotating object, such as a shaft, propeller or gear.