2013-3-6 Learning Outcomes,cont. Develop appropriate engineering models for control volumes,with particular attention to analyzing components commonly encountered in engineering practice such as nozzles, diffusers,turbines,compressors,heat exchangers,throttling devices,and integrated systems that incorporate two or more components. Use property data in control volume analysis appropriately. 4-3 Conservation of mass Conservation of mass:Mass,like energy,is a conserved property,and it cannot be created or destroyed during a process. Closed systems(implicitly used):The mass of the system remain constant during a process. Control volumes:Mass can cross the boundaries and so we must keep track of the amount of mass entering and leaving the control volume. 2kg H2 + 16kg 18kg 02 H20 Mass is conserved even during chemical reactions Mass m and energy E equivalence E=mc where c=speed of light in vacuum 1082013-3-6 2 Learning Outcomes, cont. ►Develop appropriate engineering models for control volumes, with particular attention to analyzing components commonly encountered in engineering practice such as nozzles, diffusers, turbines, compressors, heat exchangers, throttling devices, and integrated systems that incorporate two or more components. ►Use property data in control volume analysis appropriately. 4-3 Conservation of mass Mass is conserved even during chemical reactions. ►Conservation of mass: Mass, like energy, is a conserved property, and it cannot be created or destroyed during a process. ►Closed systems (implicitly used): The mass of the system remain constant during a process. ►Control volumes: Mass can cross the boundaries, and so we must keep track of the amount of mass entering and leaving the control volume. Mass m and energy E equivalence where c = speed of light in vacuum (c = 2.9979 × 108 m/s) The mass change due to energy change is negligible