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1
Why isn't this straightforward refrigeration engineering?
I'm not sure if you're referring to my post.  If so... it probably is straightforward.  The equations and math make sense, but I'm struggling to develop an intuitive understanding of how it's possible to compress the gas (i.e. do work on it), lose all the energy associated with that work as lost heat, and still have a compressed gas that's capable of doing work.   Or at least that's a somewhat poor paraphrase of my dilemma.
you aren't losing the energy as heat. Or not much anyway. Compressing the gas cools it, exchanging heat for pressure essentially.
2
Science / Re: Tesla's heat engine (split from DDWFTTW)
Last post by spork -
Why isn't this straightforward refrigeration engineering?
I'm not sure if you're referring to my post.  If so... it probably is straightforward.  The equations and math make sense, but I'm struggling to develop an intuitive understanding of how it's possible to compress the gas (i.e. do work on it), lose all the energy associated with that work as lost heat, and still have a compressed gas that's capable of doing work.   Or at least that's a somewhat poor paraphrase of my dilemma.
4
^ yep you can see the first abandoned balls attempt

It's a balls up
6
What makes you think they are not meaningful?

1) You are "documenting" them, and you have a long and tedious history of failing to apply basic rigour when it comes to.......anything..
2) You have shown no interest, or even acknowledgement of the differences in methodology used by others, and no attempt to try and compare like for like.
3) You regularly ignore things that should contribute to your EROI (eg: your vehicle usage to charge the battery).
4) You don't have a system and are nowhere near self sufficient. Basically your EROI is nothing different than me having an orange tree in my yard, ignoring it except for occasionally picking a few fruits, and then declaring, based on the high calorie/low effort, that "My system has a very high EROI", in spite of the fact that the portion with the 'high' EROI number accounts for only a small part of my diet.
7
Science / Re: Tesla's heat engine (split from DDWFTTW)
Last post by Testy Calibrate -
Why isn't this straightforward refrigeration engineering?
8
Science / Re: Tesla's heat engine (split from DDWFTTW)
Last post by spork -
Spork,

you can actually understand what is going on without invoking entropy or any other statistical property of a gas. All you need is classical mechanics.
OK - here's my VERY delayed response...

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But instead lets just let the gas in the box cool off. All the energy of the work you did on the gas is gone. The total kinetic energy of the gas in the box is the same as it was before you compressed it. But there is an important difference. There are more particles per unit volume in the box than outside the box. That means there are more collisions with the wall inside pushing out than outside pushing in. Thus there is still a force on the wall that allows us to do work. Doing so reduces the total kinetic energy to below what we started with.

This is the part that is counter-intuitive to me.  It's as if we're borrowing energy from the future - when we allow the cooled gas to come back to ambient temperature, unless...  what we've done is to effectively "rearrange" the gas such that we make it possible to extract the heat energy that was already in the gas prior to it being compressed.  Is this what the lower entropy does in effect?  Also, if this is true, it would seem there's an absolute upper limit to the energy we can get from the gas as we let it expand, no matter how  much we compressed it, as it can never give us more energy than it had prior to us messing with it at all - yes? 

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Thus you are extracting the energy you put in by compressing the gas plus some of the energy already in the gas.

But I don't see how we can extract the energy we put in by compressing the gas since all of that energy we put in was allowed to escape as heat when we let the gas cool off.


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I'm sorry if some of the explanation was overly elementary. 
Most of it was in fact already clear to me, but there's no need to apologize for making it as simple as possible - particularly when I'm asking dumb questions and making dumb assertions.  I appreciate your efforts.

10
TR Embassy and Animal Shelter / Re: Invertebrates
Last post by borealis -
beees!

One of those baby bees had a parasitic mite on it.