The Most Efficient Heat Engine Ever Made

How is the efficiency is so high on air, when 78% of air is the inert gas nitrogen? Hmmmmmmmm.(puzzled look).

Oh yes. While on this topic, http://en.wikipedia.org/wiki/Six_stroke_engine might prove interesting reading [suck/squeeze/bang/blow/squirt/chuff].

I guess ex train men will understand the technology used by these learned fellows of yester year. their opinion was writen in the days of steam locomotives and the like.

The efficiency was found by knowing the calorific value of anthracite used, and deviding that into the work performed by the engine.

GF

Hi PWSlack. What the hell are you talking about? This guy is talking about the Humphrey engine, realy it is a pump that works by igniting a gas on top of a sealed vertical tube three parts full of water. As the gas explodes the water is forced out of the bottom of the tube, there are a series of valves to admit more water, then the process is started all over again. Google Humphrey pump. Spencer.

This was never 90% efficient, not even 20%. Carnot rules.

These guys for promotional reasons said this.

It was a water pumping system made of a combined water pump and IC engine. Neither working at their optimum.

An efficient IC engine for power coupled to a properly made water pump would be a lot more efficient. It was simple though

CQ

You are missing the point. If you were to take an engine driven pump set. and a 1lb of crude oil. how many ft pounds of work will you get?The Humphrey pump was clasified as a 4 stroke engine.During the tests RAW anthracite was used to produce the gas.The efficiency of the work performed by the engine, was calculated by the total amount of Anthracite used. Your engine driven pump set would need refined fuel in order to run. It blows off about 70% of this as wast heat.

GF

OK, so what is the efficiency of the Humphrey pump/engine? (Power into water, = flow x ΔP ÷ heat power in fuel). I'd be surprised if it's anywhere near 90%.

Codey

Codey.

I aggree, thats why I want to re-read the proceedings of: The Institute of Mechanical Engineers, when they put Humphrey through the mill. His invention was not accepted with enthusiasm. they insisted on testing his "engine" and stipulated the conditions of the tests. After which, it was they, who pronounced the COP.

I read these papers, which were obtained from the London archives, by my local library in Hornchurch Essex, and that was, 40 years ago.

That was my Question: How can I get a second look.

GF

When this machine was designed, the 4 stroke engine cycle performance
diagrams were carefully considered regarding fuel economy, The long stroke
engine was in favor, the longer the stroke the better.
Humphrey designs an engine with an "infinite stroke" which goes completely
"off" the diagrams.

The fact that the exhaust is virtually cold while this thing runs,
seems to impress no one. Here we have an engine with no moving parts other than a few valves, moving a lot of water,or "liquid"
The power output of the largest Chingford pump could lift, 100 tons of water 54 ft per minute.Something like 12,000,000 ft pounds of work per minute.
12 million/33 thousand is about 363 HP.

Further development of his invention has been "stalled" in favor of "POWER
TO WEIGHT RATIO"
Now we are in the "Gasification of Biomass" age where Fuel performance is
back in favor.
The Humphrey principle deserves another innings. The materials and
construction methods have come a long way since 1908. "Where are" the simple air
compressors, or drive systems for maritime use?
Incidentally an earlier patent exists for a ships drive pre dating
Humphrey,s
Why not drill a hole in the ground and install such a devise which takes up
almost zilch real estate? This could be used for compressing air or gasses for AC and running machinery.at low fuel cost.


Gfwhell

Replying to Comment by aurizon: (Use Copy & Paste or drag text to quote the original text.)

This was never 90% efficient, not even 20%. Carnot rules.

These guys for promotional reasons said this.

It was a water pumping system made of a combined water pump and IC engine. Neither working at their optimum.

An efficient IC engine for power coupled to a properly made water pump would be a lot more efficient. It was simple though.

From Gfwhell

The power output of the largest Chingford pump could lift, 100 tons of water 54 ft per minute.Something like 12,000,000 ft pounds of work per minute.
12 million/33 thousand is about 363 HP.
If this pump combination was as inneficient as you suggest. How much producer gas do you think it used in one hour?

GFwell

I thought the link you provided was interesting and well worth the read.

Many thanks to the PWSlack.

BAB

You are fortunate to have, the only operational Humphrey engine in yor neck of the woods.

GF

Yes the Humphrey engine is just down the track about a 1000 Km, 600 + miles for the imperialists.

The site is run by the local bunch of engineering enthusiasts and does a great job of explaining how Steam engines, Internal and external combustion engines work.

BAB.

Thanks fot the info, I knew it was down your way somewhere. The boys who run it dont give much in the way of size?

The largest of the three I inspected at Chingford was 12 feet in diameter, and it could lift 100 tons of water per minute 58 ft. without producing a lake of tar.

As for moving parts, it had about 500 spring loaded bronze inlet valves, some of which would periodically drop off. this being the biggest maintenance problem.

GF

GF - wow, that's impressive. I make it about 300 kW into the water. Don't suppose you know how much gas it used? Then we could quickly estimate efficiency.

Codey

Hi PWSlack, Six-stroke engine technology was originally tried out in the 1930s by the Danes. Firms such as, Tuxham, B&W, Moller&Jochumsen and Junkers, all marine engine buiders experimented with it, but never really got anywhere with it. That is not to say that with modern technology we will overcome the problems these firms had. Spencer.

It looks like the humphrey depended on local wood for fuel. When the wood ran out, the life of the machine became limited.

Had this type of machine been truly more efficient than other pumping means it would have spread widely.

So it is a simple device, replaced by more comples and more efficient machines where the extra efficiency made up for the extra cost and then some.

Rizo

You are probably correct in assuming the pump was an economic failure.

This assumtion does not effect the machines thermal efficiency.

The 12ft unit I inspected probably weighed in at about 150 tons befor assembly

not including the cost of the excavations for its installation or the cost of the gasification plant needed to run it.

The Victorians seemed to have little concern for things like Power to weight ratio, this being probably due to their expectations for the life of their products. " It will last 100 years or more. so lets do it properly".

As a water pushing engine it could have had definate advantages and cost savings in the maritime field had it been persued.

GF

I still see no fundamental difference in thermodynamic cycle that would make it more efficient than any other SI (or at least internal combustion) engine. I bet if you replaced the screw with a water jet from such a propulsion system you'd avoid quite big transmission and conversion losses though.

There has to be a reason why such a thing hasn't been seen?

Dea wrench.

I guess in the old days, they decided that the only way to get work out of fuel was to set fire to it. If this was done in a suitable enclosure with a suitable ammount of oxygen there would be a sudden evolution of hot gasses. the pressure and temperature of which could be utilized for doing work. Untill the pressure and temperature is all used up.

On modern high speed engines with equally high power to weight ratio, a considerable ammount of thermal efficiency is traded off ,by discarding hot potential energy with such force that it makes a Harley owner feel warm inside. These gases constitute approximately 70% of the available energy within the fuel. The expanding gasses on the power stroke of a Humphrey engine are retained within the explosion area untill the temperature and pressure has been "fully utilised". other than a slight hissing noise and a temperature to match that of a babies breath signifies the efficiency I speak off.*

GF

Are you implying that the Harley's exhaust is that cool? Or have I completely misunderstood what you were trying to say? Sorry if the latter.

Please re-write (and re-proof read!) so that I can understand you better. Thanks.

Are you implying that the Harley's exhaust is that cool? Or have I completely misunderstood what you were trying to say? Sorry if the latter.

Andy Germany

Andy,

I am suggesting that the most "inefficient engines" make the most noise and heat.

The Humphrey engine did not require a "Muffler" the exhaust pipe could have been made of PVC had they had some in those days. The crisp note of a Harley is the sound of fuel being turned into heat and noise, why not buy a crow scarer on wheels?.

GF

You are so right my friend, sorry that I did not understand the first time.....

Hello GF - but you haven't spoken of any efficiency. As far as I can make out from this thread, no figures are available, or data which would enable us to estimate. Be very interested to see something.

Also, the power emitted as sound, even from a noisy Harley, is only a few watt, not enough to have a noticeable effect on efficiency.

Cheers....Codey

Codey.

My first mail on this subject asked, "How". confirmation, of what I had read ,

In, the Proceedings: The Institute of Mechanical engineers in London UK.

Late in, 1898. Could be obtained?

I related that, which I could remember, to CR4, thinking, perhaps a current member of this Institute might read this. And point me in the right direction in re affirming what I had read.

The efficiency of a heat engine is the percentage of work obtainable from the potential energy contained in the fuel it uses.

Today we are lucky to obtain 30%.

In 1898-9, the Humphrey engine was tested by the Institute of Mechanical Engineers in London at least twice. The overall efficiency was stated as being in excess of 90%.

The reasons given were as follows:

Fuel of known thermal value was carefully weighed and used for the tests. The work performed by the engine was recorded.

The fuel was exploded above a column of water, and allowed to dissipate its energy to ambient pressure and temperature in the execution of performing work.

The design of the explosion chamber, allowed the piston to change shape relative to the acceleration of the water column and the pressure exerted upon it during the power stroke.

There were many graphs of Carnot, Otto, Rankin etc, showing the COP.

The Machine I inspected at Chingford had a 12 foot Diameter Cylinder head and probably weighed in at 150 tons together with its play pipe.

It could only raise 100 tons of water to 58 ft head per minute, which probably explains why it never caught on.

A multiple of these, designed in to, say, an ocean going vessel, might be a different story.

The cost per KW converted to noise on a Harley: Priceless!

GF