Consider the steady-state flow in a combustion chamber where heat is added by burning fuel. neglect friction and consider that the thermodynamic properties of the combustion gases are the same as those of air. data: m1 = 0,4; p1 = 557kpa; t1 = 604k; t2 = 900k; a = 0,0185m²; find: a) mass flow rate; b) m2; c) the addition of heat per unit mass and the rate of heat exchange; d) express the rate of heat addition as a fraction of the maximum rate of heat addition

Amass of m 1.5 kg of steam is contained in a closed rigid container. initially the pressure and temperature of the steam are: p 1.5 mpa and t 240°c (superheated state), respectively. then the temperature drops to t2= 100°c as the result of heat transfer to the surroundings. determine: a) quality of the steam at the end of the process, b) heat transfer with the surroundings. for: p1.5 mpa and t 240°c: enthalpy of superheated vapour is 2900 kj/kg, specific volume of superheated vapour is 0. 1483 m/kg, while for t 100°c: enthalpy of saturated liquid water is 419kj/kg, specific volume of saturated liquid water is 0.001043m/kg, enthalpy of saturated vapour is 2676 kj/kg, specific volume of saturated vapour is 1.672 m/kg and pressure is 0.1 mpa.

Most leaks in reciprocating air compressors can be detected and minimized by: (clo4) a)-detecting leakage areas using ultrasonic acoustic detector. b)-tightening joints and connections c)-replacing faulty equipment d)-all of the given options

Have a greater impact on maintenance productivity than any other support group. (clo5) a)-the top management b)-inventory and purchasing c)-sub-contracting d)-cmms