CHEN 3101 Lecture Notes - Lecture 1: Plug Flow, Alsn, Mesa
Document Summary
generic devices piston ports k = 1 k = 2 k = 3. # inlet outlet ports k = 1 k. Mass balance: m(t) = mass w/in system boundaries dm/dt = accumulation. = mass flow rate into system @ port k inlets (inputs into the system) > 0 outlets < 0. Energy is carried into or out of the system with material (aka advection) Work done on system pressure exerted @ ports (flow work) Imagine boundary shoved up the pipe a bit system energy/mass in port k. [=] mass/time * energy/mass --> {rate of energy advection in port k} E = total energy = u + ekin + epot advection. Chose mass basis to simplify specific kinetic and potential energies. Examples: imagine you have a really high water fall (open system) k = 1 k = 2. Chen thermo page 5 another example: rocket here, kinetic energy matters more k = 1.