Talk:X-engine

There is no explanation of how this works. There is no diagram of the Thermodynamic Cycle of this engine. The super cool but useless animation just shows gas velocity and nothing about the combustion cycle. Either the writer is unable to properly explain what they have or they have nothing to explain. This article shows the mechanical movement but that does not explain the all important heat cycle. The LiquidPiston web site is just about features with zero science. Features without scientific explanation is just marketing. — Preceding unsigned comment added by 2603:7081:D03:EEFA:79E4:8414:802A:4AB6 (talk) 14:29, 6 June 2023 (UTC)


 * Here's a video about the engine. Like I mentioned below, it's related to the Cooley engine, and is in fact not an inverted Wankel.
 * https : //youtu.be/Yc17oucI6jM Tkircher (talk) 04:49, 15 July 2023 (UTC)

Did LiquidPiston write this?
This article reads like marketing copy. Wikipedia is not a place for companies to promote their products.

Until this motor is proven, in production, and measured, hailing it as a revolutionary new invention and quoting unverified projections from the manufacturer is not warranted.

This article should be nominated for deletion.

Another option would be to change the article from one about a perported invention to one about the company which is trying to get funding from investors. — Preceding unsigned comment added by 4.59.197.248 (talk) 23:16, 28 May 2021 (UTC)


 * Regardless who wrote the article, the engine seems to exist and work. According to LiquidPiston they got a contract with Air Force about one year ago. So, I don't see reasons for deletion. Instead I see reasons to improve the article, so that it would look less like an advertisement. ⸻Nikolas Ojala (talk) 10:31, 13 April 2022 (UTC)

Rotary?
Is this engine supposed to be a Rotary engine or is it supposed to be a Pistonless rotary engine? --Athol Mullen 00:42, 19 September 2007 (UTC)


 * According to the article Piston: "It is the moving component that is contained by a cylinder and is made gas-tight by piston rings." I'd say LiquidPiston engine is pistonless. ⸻Nikolas Ojala (talk) 11:00, 13 April 2022 (UTC)


 * It's a rotary piston, the whole piston article is flawed as there are plenty of pistons without piston rings, and their motion can be both linear and angular. 195.196.97.2 (talk) 08:07, 4 November 2022 (UTC)


 * Nomenclature can be difficult, particularly for titles which need to be concise. Pistons can come in many forms. However Wikipedia has decided for simplicity to differentiate conventional piston rotary engines (as used in early aircraft, where the pistons and cylinders rotated around a fixed crank shaft) from other rotary engines which do not have conventional pistons. The so called Liquidpiston engine is linked to in the pistonless rotary engine article. It's a cludge but until someone has a better idea, it works OK.Lkingscott (talk) 11:09, 15 December 2023 (UTC)

External links modified
Hello fellow Wikipedians,

I have just modified one external link on Liquidpiston. Please take a moment to review my edit. If you have any questions, or need the bot to ignore the links, or the page altogether, please visit this simple FaQ for additional information. I made the following changes:
 * Added archive https://web.archive.org/web/20120229142013/http://papers.sae.org/2010-01-1110/%2C to http://papers.sae.org/2010-01-1110/%2C

When you have finished reviewing my changes, you may follow the instructions on the template below to fix any issues with the URLs.

Cheers.— InternetArchiveBot  (Report bug) 17:22, 16 May 2017 (UTC)

I'm surprised that nobody has pointed out that this is a Cooley engine: http://www.douglas-self.com/MUSEUM/POWER/rotaryengines/rotaryeng6.htm#cool

Tkircher (talk) 08:12, 26 July 2022 (UTC)


 * Not quite. It looks like a derivative of the Umpleby engine, which was an internal combustion derivative of the Cooley engine. 80.208.71.81 (talk) 06:25, 10 December 2022 (UTC)

Wrong picture
The picture is of a standard Wankel engine. The Liquid Piston (what a goofy name) concept is the inverse of that. The wipers are on the fixed part of the engine rather than on the rotor. The fixed part is the triangular part. The rotating part has the smooth surfaces with no apexes. WithGLEE (talk) 22:27, 11 February 2023 (UTC)


 * I have just replaced it.  Stepho  talk 23:33, 11 February 2023 (UTC)

Compression ratio and name
The article states demonstration of this engine with a Diesel cycle with 26:1 compression ratio. This would create enormous amounts of NOX emissions, which are one of the most significant pollutants from Diesels which are trying to be curbed. Was such a compression ratio used simply to demonstrate possibilities or is it really expected to be used at that ratio and if so how would NOX emissions be mitigated?

The article is not very informative about why this engine should be better than anything else and the name is simply a marketing gimmick and nothing to do with engines which have an actual liquid piston. Lkingscott (talk) 11:09, 15 December 2023 (UTC)


 * It is essential to realize where would these engines be used: Some military UAV and other such gadgets with small power and high power to weight ratio. NOX emissions mean nothing. ⸻Nikolas Ojala (talk) 12:45, 15 December 2023 (UTC)