Octane (c8h18) is burnt with dry air in a steady-flow constant pressure combustion system at a pressure of 15 bar and an equivalence ratio of 0.666. the fuel enters the combustion chamber as liquid at 25°c, whilst the air enters at a temperature of 600 k. the product s leaving the combustion chamber are in equilibrium at a temperature of 1800 k, and consist solely of n2, o2, h o, co no write down the stoichiometric and actual combustion equations, and determine the concentration of nitric oxide (no) in the products of combustion. calculate the heat transferred from the combustion chamber during combustion per unit mass of fuel. why might the concentration of nitric oxide in the exhaust differ from the equilibrium prediction?

Tom is having a problem with his washing machine. he notices that the machine vibrates violently at a frequency of 1500 rpm due to an unknown rotating unbalance. the machine is mounted on 4 springs each having a stiffness of 10 kn/m. tom wishes to add an undamped vibration absorber attached by a spring under the machine the machine working frequency ranges between 800 rpm to 2000 rpm and its total mass while loaded is assumed to be 80 kg a) what should be the mass of the absorber added to the machine so that the natural frequency falls outside the working range? b) after a first trial of an absorber using a mass of 35 kg, the amplitude of the oscillation was found to be 10 cm. what is the value of the rotating unbalance? c) using me-3.5 kg.m, find the optimal absorber (by minimizing its mass). what would be the amplitude of the oscillation of the absorber?