PASCO SE-8575 VISIBLE STIRLING ENGINE - Manual (Page 11)

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012-06055A The Visible Stirling Engine
®
DEMONSTRATION:
An Engine That Runs On Ice
Setup
Set the SE-8575 up to run on ice chips, ice cream, or frozen yogurt. Detailed instructions are in
the Operation section of this manual. Start it running and ask the following questions.
Questions
➀
What is the source of energy to run this engine?
➁ Since there is no such thing as a free lunch, who paid for the energy to make this engine run and
what company did they pay it to?
➂ After the SE-8575 has been running for some time, do the Power From Your Fingertips demo as
explained in the operations section. Who paid for this energy to make the engine run faster and
who did they pay it to?
➃
Would it be possible to have a full power engine that had zero pollution and used the heat from
the room as a hot source.
➄
Calculate the Carnot efficiency of an engine running with liquid nitrogen as a cold sink and a
72°F (23°C) ambient hot source.
➅
Liquid nitrogen is readily available. What determines whether it would be a good idea to build
an engine like this?
➆
Since the air is roughly 80% nitrogen, would an engine like this cause any pollution?
➇ When an engine is running on a heat source the Carnot formula determines how much of the
heat can become useful work. In this engine as in most engines the majority of the heat that
could become useful work doesn’t become useful work. What happens to this heat? Identify the
specific loss mechanisms.
➈ Internal combustion four stroke engines have one power pulse every other trip of the piston.
Stirling engines have two power pulses per trip of the piston (one going up, and one going
down). All other things being equal (which they never are) how much smoother should a
Stirling engine be than an Otto cycle engine?
➉
Are you likely to see a Stirling engine offered for sale in a car? Why or why not?
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Would Stirling engines be good candidates for powering submarines? Stirling engines are quiet
and submarines like quiet.
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Would Stirling engines be a good source of auxiliary power generation for yachts? Good
cooling water is available, and people on yachts like it quiet too.