HW 7 due today
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HW 8 today: due Wed, Oct 26
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Homework
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More Ch. 4 on open system examples•
"Steady
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state" problems
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Today:
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General problem solution procedure for thermo problems
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Identify what is being requested in a problem
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Summarize given info
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Sketch system, then identify system boundary (i.e. CV boundary)
along with the mass and energy flows crossing the CV boundary
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Create a state table and fill
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in known info
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Create a list for your "Engineering Model" assumptions (e.g. steady
flow, adiabatic, etc.)
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Setup
Begin your solution by applying your basic equations. Start with the
one that seems most directly relevant to your problem (e.g. if asked
for heat transfer, use the first law; if asked for a mass flow, use
conservation of mass; etc.).
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Conservation of mass
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Conservation of energy (1st law of thermo)
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State relationships
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The 2nd law of thermo
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Conservation of momentum (Newton's 2nd law)
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we don't use
this in thermo, since we focus on energy
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related problems
○
Conservation of angular momentum (another mechanics equation
that we don't use in thermo)
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Your basic equations are:
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Analysis
ME 291 L14 10
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19
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Wednesday, October 19, 2016 8:57 AM
ME 291
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