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Steam locomotive and aircraft engines with mechanical steam recompression

Posted by novice 
Steam locomotive and aircraft engines with mechanical steam recompression
July 12, 2020 06:41PM
Several engineers designed steam powerplants with a mechanical recompression of exhaust steam.


" ... The Paragon-Cristiani Compressed Steam System was a Diesel-steam hybrid that used the steam for power transmission rather than power generation. The actual prime mover was intended to be a Diesel engine. It was based on patents held by Severino Cristiani and Secondo Sacerdole of Italy, and was promoted in England by Captain William Peter Durtnall.

Water is not boiled directly- instead the exhaust from a standard pair of cylinders is compressed by the Diesel engine, stored in an HP reservoir and released back to the cylinders by the regulator. Presumably distilled water was used in the circuit to prevent scale formation.
This is a vapour recompression scheme as used in the Holcroft-Anderson Recompression Locomotive..."

There was also a project of an aircraft with the hybrid steam-diesel powerplant based on William Durtnall design:

"By P. J. Risdon

Popular Science Monthly, February 1922, p.76

Steam Motor May Prevent Disastrous Airship Fires

British Officer Designs New Aircraft Engine which Will Reduce Danger and Develop Greater Power with Less Fuel Waste

Will the use of steam power in place of gasoline reduce the dreaded danger of fire in aircraft? Will the steam-engine, too, develop greater power with less waste of fuel, permitting the operation of the long-prophesied passenger airlines?

Captain W. P. Durtnall, formerly of the British Royal Air Force, has designed a steam-motor for aircraft which, he hopes, may prevent a repetition of the frihtful ZR-2 disaster. He claims that his motor may even be placed inside the gas-bag of a rigid airship, or that it may be carried within the wings and fuselage of a huge plane without the slightest danger that the craft will catch fire.

The reliability of the steam-engine is combined with the lightness of the internal-combustion motor in the design of Captain Durtnall's new engine. The power is furnished by an oil-burning Diesel-type motor. The propellers are driven by steam. Heat from the internal combustion cylinders, usually wasted, is utilized to generate low-pressure steam in high-pressure steam reservoir. Thence it is led to steam-engines, drives the propellers, and exhausts into a low-pressure cylinder, from which it returns to the Diesel engine to be compressed again. All the piping, reservoirs, and engines are lagged to prevent the loss of heat. The steam is used over and over in a closed steam circuit.

No gasoline is carried. The fuel consists of heavy oil into which one might safely throw a lighted cigar. As the propellers are driven by steam, there is no reason why the engines cannot be placed in what is their logical position—on the body of the airship itself. In the past, gondola engine cars have been slung to the bottom of the hull, like a towboat, simply because a gas-engine near the hydrogen-filled bags would have made an explosion almost inevitable.

The use of steam should assure increased reliability. By stepping up the speed of the slow-running Diesels through variable speed gears, the propellers of the Durtnall plane could be run at any speed desired without likelihood of engine failure.

In giant passenger planes, the double acting steam-engines would be placed inthe cantilever-type wings. The transforming engine in the fuselage would be separated from the forward passenger cabin by a collision bulkhead

Left—A cross section of a rigid airship, with the engine-rooms inside the hull and transforming engines in the keel space. Center Plan of the transformer for converting low-pressure steam into high-pressure steam. Right —Arrangement of the engines

Modern steam recompression engines for automobiles and aircrafts with efficeincy up to 40%:

[patentimages.storage.googleapis.com] - Calvin Williams steam engine



Edited 1 time(s). Last edit at 07/12/2020 07:27PM by novice.

Re: Steam locomotive and aircraft engines with mechanical steam recompression
July 13, 2020 09:01AM
Keep in mind you're talking about a number of different things. The Paragon-Cristiani system basically used steam in place of compressed air; hydraulics are probably better and electric drives are much better yet.

The McCollum-Anderson system envisioned steam recompression as a way to improve efficiency by reducing the amount of energy lost in condensing systems, thereby forgoing loss of latent heat in the condensing process.

The Williams brothers were claiming that recompression inside the engine could drastically improve efficiency but their claims for 40% efficiency appears to be a lot of hocus pocus ---- for one thing, their advocates called it "The Williams Cycle" when there was nothing vaugely resembling a new cycle. You should always take it as a warning sign when people start taking credit for non-existent things. Their claim to inventing recompression to admission pressure is specious since it was well understood by competent engineers dating back to the 1880s and the invention of a valve to vent recompression to the steam chest was first patented by a Frenchman, Marquadt, back in the 19th century.

The brothers got a lot of press in the 1960s when testifying in front of the Senate on auto pollution, at which point a variety of outrageous claims were made. The hearings were under the auspices of Edmund Muskie, who had presidential ambitions, and he wasn't about to let facts get in the way of headlines. The brothers were incredibly secretive and paranoid, so no one actually got to test their engines in a lab. General Motors Research (GMR) built a steam car that was designed to replicate the Williams engine --- mechanically it was equivalent although of generally superior design and construction --- as would be expected. GM did some initial testing at lower temperatures but never advanced the testing program any further since the efficiencies obtained were dead on with what traditional thermodynamics predicted whereas they should have been much higher if there actually was anything to the Williamses claims. GM apparently went to this effort and expense just to get the Senate off their backs as the they could easily do thermodynamic calculations and the head of the program (Dr. G.A. Ammann) was apparently quite familiar with uniflow engines having quoted Dr. Johann Stumpf in his analyses. Ammann apparently got the job because he was simultaneously heading up groups working on Sterling and gas turbines. In fact, the SE-101 boiler was a bit of a marvel because it was a parallel flow, once through boiler and it seems to have worked correctly on the first try; the team had some good control engineers and they modified the control box from their Stirling engine program to regulate water and combustion.

And, let's not forget Stumpf He did extensive testing of uniflow engines in the early part of the century and wrote a book on the subject with an updated version coming out about ten years later. His book contains numerous test results and mathematical analysis, including the effects of clearance volume and recompression. If there was anything to the Williamses arguments, he would have ferreted it out decades earlier.
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