Besler Steam Plane

[onetrack]

The Americans need to use twice the thickness of wiring than we do, to get their backwards 110V system to work, too.

 

OME, you've got me with "kangarooing the dike"? Never heard that one before, and I've been around for a while, and been in with some roughies.

[facthunter]

110 Volt won't kill you though. 240 is right in the best place to do so Transmitting long distances requires very high voltages.Nev

[onetrack]

Nev, I've taken a 240V jolt through serious inattention, and I'm still here. Sure smartened up my attention, though.

[Geoff_H]

I had one too many years ago. It went across my body. I had to lie down for the rest of the day. These days I would spend a day hooked up to a heart monitor in a hospital if it happened. All of us need to do this if it is an across the heart shock. In 1973 I acquired a then state of the art earth leakage circuit breaker, had a few shocks since then, don't even feel the shock, but trips the house off.?

[facthunter]

I've done it about 4 times and if you are unlucky one is enough. I don't use salt so may have a higher resistance I don't wish to chance it though. I might slip the timing on the ticker which has so far done ok. I lost a few mates when I was young. Drill into a wall or work under the house. Those earth leakage sensing circuit breakers are life savers in domestic power supplies..Nev

[Bruce Tuncks]

It's the current not the voltage that kills you. A 240 volt AC wire onto dry skin and out through rubber soled shoes on carpet is not much current. A 120 volt through wet skin and out through wet feet onto wet concrete may be thousands of times more current. Try playing with an ohm meter and see for yourself.

[Bruce Tuncks]

People are extremely variable with reaction to electric shock. There is a story about a farmer's wife dying as a result of an electric fence boot. On the other hand, the first guy to experience the electric chair took twenty minutes to die.

[old man emu]

you've got me with "kangarooing the dike"?

 

"kangarooing" is the act of squatting over your toilet.

 

 

 

Then there's the other practice that is associated with a religion:

Edited May 11, 2020 by old man emu

[facthunter]

Bruce, the less voltage with the same resistance the less current flows. Ohms law somewhere. .Nev

[facthunter]

You have more problems with Sinking the engines with sea planes. Nev

[old man emu]

Ohm's Law

 

Electrical injury is a physiological reaction caused by electric current passing through the body. The injury depends on the density of the current, tissue resistance and duration of contact.

 

The Figure shows a person connected to a voltage source. There are connections to the left hand and the left foot. The “total body resistance” of the person is composed of the very low (approximately 300 Ω) internal body resistance plus the 2 skin contact resistances. The skin contact resistance will usually be between 1000 and 100,000 Ω, depending on contact area, moisture, condition of the skin, and other factors. The skin thus provides most of the body's protection from electric current.

 

alt=An external file that holds a picture, illustration, etc. Object name is eplasty09e44_fig3.jpghttps://www.ncbi.nlm.nih.gov/pmc/articles/PMC2763825/bin/eplasty09e44_fig3.jpg[/img]

 

The total resistance from red to green is the sum of the resistances, let's say dry, soft skinned hands ~ 50,000 ohms, and internal resistance of 300 ohms.

 

50,000 + 300 + 50,000 = 100,300 ohms.

Voltage supplied is 240 VAC

Current = V/R = 240/100300 = 0.00239 Amps = 2.39 MA

 

Currents at about 1 milliamps (MA) can cause tingling. Going up to 75 MA can actually trigger ventricular fibrillation which could lead to death. A reading of 1500 milliamps would cause severe tissue and organ damage.

[Geoff_H]

DC is far more lethal than AC. AC let's go 100 times a second. DC clamps muscles.

[facthunter]

50 Hz I think, AC still clamps muscles. The % time you aren't getting current is small and muscles only contract. Touching with the palm side of your hand is obviously worse than the back of it. Worth remembering that solar is DC before it goes near the inverter and the panels are usually in series. I think I've seen an open circuit voltage of 400 on mine.(22 panels) would obviously not make your day. Nev

[Geoff_H]

No it's 100 Hertz. Each half of the wave clamps. The noise a transformer makes is always 100hz

[facthunter]

50-60 Hertz according to ANU for East Australia grid. Nev

[spacesailor]

50-60 Hertz WAVE.

fifty at the top of the cycle.

and fifty at the bottom of the wave-form.

Makes sense to me.

spacesailor

[Geoff_H]

We only have 50hz in Australia. All grids, even outback grids are 50hz. 50hz within around +/- .01 hz

[old man emu]

The hertz is defined as one cycle per second. The hertz relates to a system where a feature of a Dependent Variable varies over time. In the illustration, the Dependent Variable is the Amplitude (or distance from a reference point), and the Independent Variable is Time. Probably the best way to describe a "cycle" is graphically. In this illustration, one cycle is the distance from one peak to the next, or from one trough to the next.

 

If in this illustration T = one second, then the illustration shows one Hertz. If you squeeze the peaks and troughs together, you get more cycles in the time period, "T". More cycles in the same length of time means more hertz per second.

[Flightrite]

It's the current not the voltage that kills you. A 240 volt AC wire onto dry skin and out through rubber soled shoes on carpet is not much current. A 120 volt through wet skin and out through wet feet onto wet concrete may be thousands of times more current. Try playing with an ohm meter and see for yourself.

Correct, I used to get shocked a bit when I was playing around with dads old valve radios, high V low Amps....soon learned thigh!? Regardless of AC, DC or any other sexual preference it still 'hertz'?

[Bruce Tuncks]

All good correct stuff. Except that the resistance of dry through rubber soles and carpet is more like a million fold less than the same circuit wet. Internally we are wet and salty.. the same saltiness as the sea from which our ancestors emerged. How clever of nature to make electrical nerves work in a wet and salty environment huh.

Getting back to lethal shocks... I think that the electric chair was metal and the executionee had a metal helmet with salty goo to make a good connection. They blacked out more and more of the city as they slowly killed him. The helmet was one connection and the chair was another. I think... it is not as much an interest of mine as is Jabiru maintenance, and I guess I am speaking for most of us here.

One thing about AC is that the peak voltage is 240 times root 2. It is higher than the nominal but as has been pointed out it goes through zero too.

[kgwilson]

Volts = pressure

Amps = Current

Ohms = Resistance

 

[facthunter]

IF you need that diagram you shouldn't be an electrician. It's one of the hardest courses of the normal trades. Nev

[Old Koreelah]

We only have 50hz in Australia. All grids, even outback grids are 50hz. 50hz within around +/- .01 hz

Thank goodness for government intervention in this country! Many aspects of Japan are incredibly well-run, but the electricity grid is a mess:

https://www.quora.com/Why-does-Japan-still-use-50Hz-and-60Hz-in-their-electrical-system

[kgwilson]

IF you need that diagram you shouldn't be an electrician. It's one of the hardest courses of the normal trades. Nev

Not for a Sparky but the average person believes that just high voltage is the problem. Without current it is ineffective but with high amperage it is deadly and with even higher resistance it again become ineffective. You can generate 25,000 volts in static electricity buildup in your own body. It creates a good spark like when touching a doorknob or the car door handle especially when humidity is low. It will give you a bit of a shock but isn't at all dangerous as there is virtually no current.

[old man emu]

 

The possibility of using a steam engine in aviation will depend, as with all power generating systems, on the total weight of the system compared with the weight of an internal combustion engine. Here is a video of a proof of concept that shows that, with further refinement, a steam engine could swing a prop.

 

A really big advantage of a steam engine for an aircraft is that its power output is not diminished by air density at altitude. The steam engine relies on increasing the vapour pressure by heating water. Boiling is the process by which a liquid turns into a vapor when it is heated. The boiling point of a liquid depends on temperature, atmospheric pressure, and the vapor pressure of the liquid. When the atmospheric pressure is equal to the vapor pressure of the liquid, boiling will begin. The purpose of the heat source in a steam engine is to vaporize water, so, if the atmospheric pressure is reduced, then the vaporization occurs at a lower temperature. This produces "wet steam" which is a mixture of gaseous water and liquid water droplets. If wet steam is heated further, then the droplets become gaseous, increasing the pressure if the whole mixture. If the boiler tubes are kept at 100 C, then at altitude, the boiler will produce superheated steam.

 

In the proof of concept model, it is easy to see that certain modifications are needed to make the system practical. A pump would replace the pressurized water tank to feed water to the boiler. Perhaps a condenser could be fitted to recover some of the water and return it to the tank. Maybe a tank of compressed air could be included to improve fuel combustion at altitude. There are probably many suitable light-weight materials that could be used in the construction of the engine components to further reduce weight. Fuel storage could be adapted from automotive systems.