Yes, yes, yes, Yes, this is what I would suggest as well.. (although I would
just use a smaller inflatable spa you can set those up on any cement floor).
That was my suggestion a few years back when they were asking about an X prize
type of event.
People will talk about heat loss and so on. But with some floating bubble wrap
that could be kept down. If they are really getting 4 to one, it should be
easy to see with something like the "heat a tub of water" approach. You
wouldn't have all the flow measurement questions. No water/steam problems, no
EMF interference with your temperature sensors. You would need to mix it from
time to time with a paddle or something.
I also would like to see a fuse in their input power line to show that at no
time the current exceed some set value.
Date: Mon, 12 Aug 2013 14:40:19 -0400
Subject: Re: [Vo]:Suggestions for a more effective demonstration
From: janap...@gmail.com
To: vortex-l@eskimo.com
Keep it simple.
Fill a 10,000 gallon insolated tank
truck with 20C water, and run it in a loop to the Ni/H reactor. When the
temperature of the water in the truck gets to 90C, the case is proven.
On Mon, Aug 12, 2013 at 2:24 PM, Jed Rothwell <jedrothw...@gmail.com> wrote:
Defkalion's demonstration wasn't bad. Any demonstration is tough. Something
always goes wrong. It wasn't bad, but it could have been better. I have done
demonstrations and I have taught and given lectures so let me offer a few
suggestions based on this experience.
Practice, practice, practice. Rehearse beforehand. Be sure you can comfortably
complete the presentation in the time allotted. This was their biggest failing.
Set up your props beforehand. As I explain below, in this case I would have put
a black drop cloth on the wall and brought in a meter stick, a weight scale,
and a bucket of water with a thermometer in it.
Make yourself clear. Get to the point and stick to it.
You need not write out every word, but it is a good idea to write down your
talking points in the order you intend to present them.
Here is the sort of thing I would have said:
". . . The inlet temperature is 21°C, the outlet is 115°C. Here on the screen
we are computing enthalpy by the heat capacity of water. We ignore the heat of
vaporization. However, at this outlet temperature we know the water has
vaporized. Let's prove that. Let's take the outlet tube from the sink and hold
it up next to this black drop cloth. [Holding meter stick next to plume.] As
you see the plume of steam is around 80 cm long. The first 20 cm are invisible,
which means the steam is dry.
Now let us show that our flowmeter is correct and the water is flowing at 500
mL per minute. We will also show that the steam has about 1130 kJ of enthalpy
per minute. We have placed this bucket on the weight scale. As you see it has
20 kg of water in it, and the water temperature is 21°C. Now were going to
submerge the hose under the water for about a minute and see how much water
condenses and how much the entire mass of water heats up. Starting NOW.
[Splash! 'Buku buku buku' as bubbles say in Japanese]
[A minute later] Okay we removed the hose after one minute three seconds. The
weight of water has increased by 460 g. Some of the steam escaped from the
water but most of it condensed. We see that the temperature has risen to 31°C .
. ."
And so forth.
Prepare your tables and spreadsheets beforehand so you can describe results
smoothly without stopping to do a lot of arithmetic. You need not state that
the heat of vaporization is 2260 kJ per kilogram. The viewer can look that up
later on. You need not explain that the bucket when empty weighs 820 g. The
viewer knows about how much a plastic bucket weighs, and can see you have taken
that into account. Skip the details; get to the point.
As I said before, you demonstrate every key point twice, by two different
methods. Ideally, one method relies upon precision instruments and the second
method depends on first principles that are easily understood and easily
measured, even if they are somewhat crude. The two methods must be completely
different so that a single artifact cannot cause both to be wrong.
People sometimes say that in a lecture you should tell the audience what you're
going to say; tell them what you have to say; and then tell them what you just
told them. I think this is going too far, but it does not hurt to repeat your
key points at least once.
I assume the people at Defkalion are doing similar demonstrations for potential
customers and investors. So I think they should polish up the presentation and
make it more convincing.
- Jed
