Papin's Paddleboat

1704: Denis Papin has a very public falling out with Leibniz (POD)

1707: Papin returns to London from Germany and present papers to the Royal Society on his new steam engine and describes the steam boat experiments he conducted in Kassel in 1704 through 1707. In TTL he is not snubbed by the Society and is actually favorably received by Isaac Newton (an enemy to Leibniz) and befriends Thomas Newcomen.

1709: Papin receives desired financing and begins steam paddleboat service in England.

---

So basically: WI steam boats had been commercially successful 98 years before they had in OTL?
 
1704: Denis Papin has a very public falling out with Leibniz (POD)

1707: Papin returns to London from Germany and present papers to the Royal Society on his new steam engine and describes the steam boat experiments he conducted in Kassel in 1704 through 1707. In TTL he is not snubbed by the Society and is actually favorably received by Isaac Newton (an enemy to Leibniz) and befriends Thomas Newcomen.

1709: Papin receives desired financing and begins steam paddleboat service in England.

---

So basically: WI steam boats had been commercially successful 98 years before they had in OTL?
At a wild guess, they're not going to be very useful. How much had the state of art of steam engines advanced in 100 years?

Early steamboats even OTL were pretty much fuel-hogs, which rather limited their use. A century earlier, it'd be even worse, no?
 
Airship Armada,

Without a separate condenser, Papin's aren't going to amount to anything.

It's rather telling that Papin called his devices "steam digesters".


Bill
 
Airship Armada,

Without a separate condenser, Papin's aren't going to amount to anything.

It's rather telling that Papin called his devices "steam digesters".


Bill

His Steam Digesters were an earlier invention. His steam boat experiments happened 15 years afterwards.

In order for the boats to be viable they need to be used in areas of cheap fuel and poor roads (in OTL paddleboat were often unable to compete in areas where good roads allowed goods to be carried upstream more cheaply). Fortunately bad roads were plentiful in the 18th century. The American colony in Virginia seems like a good place for lots of early steam boats.
 
Whew, i'm having a hard time finding good info on Papin.

That said, AFAICT Papin's second type of steam engine (as opposed to the steam digester of 1679 and the engine he designed in 1690) was inspired by drawings of Savery's engine that Leibniz sent to him in 1705.

Amending your TL to take that into account:
1704: Denis Papin has a very public falling out with Leibniz (POD)
1707: Papin is working on something that, while doubtless fascinating, has nothing at all to do with steam engines or boats

Uncalled-for sarcasm aside, if Papin can continue development of his boat, it still won't be commercially successful right away. There will still be technical bugs to work out, and even then adoption won't be automatic or neccessarily widespread.

IMHO, while it may be feasible for Papin to go down in history as the inventor of the steam boat, it won't be a commercial success in his lifetime. I will point out that prior to Fulton's steamboat, there were relatively successful steamboats being built as early as 1785, that he would have had knowledge of. I'm finding names of John Fitch, James Rumsey, Briggs & Longstreet, and memory brings to mind the Marquis d'Abbans and his Pyroscaphe. So we're running at least 20 years of development from the time when serious attempts at building steamships began to when Fulton brought them to commercial success. And that's with another century of development in steam engines. So, IMO, you might be able to plausibly get a commericialy successful steamship by the 1750s.
 
His Steam Digesters were an earlier invention. His steam boat experiments happened 15 years afterwards.


AirshipArmada,

And that "steamboat" still didn't have condensers.

In order for the boats to be viable they need to be used in areas of cheap fuel and poor roads...

No. In order for steamboats to be viable in areas of cheap fuel and poor roads they need separate condensers so that the engines were not of the atmospheric type.

Newcomen produced the first commercially viable engine building on the work of both Papin and Savery. Like those of his predecessors, Newcomen's engine was an atmospheric one. Instead of steam pressure moving the piston, the designs produced by Newcomen, Papin, and Savery relied on a vacuum created by condensing steam which allowed atmospheric pressure to move the piston.

Simply put, in Papin's design vacuum sucked the piston "down" rather than steam pushing the piston "up". This meant that the design sucked both literally and figuratively.

Because they relied on relatively weak atmospheric pressure, the pistons used in Newcomen's and Papin's designs had to be much larger. Because they relied on condensing steam within the piston cylinder, which in turn required repeatedly heating and cooling that cylinder, Newcomen's designs were painfully slow and hideously thermodynamically inefficient. Papin's designs were no different.

Unless Papin makes the same leap Trevithick did, his designs aren't going to be worth a damn for vehicles of any size. While his designs allowed stationary engines to be used in more locations, even Watt's improvements on Newcomen's designs didn't reduce piston and piston cylinder size enough to be used in vehicles.


Bill
 
No. In order for steamboats to be viable in areas of cheap fuel and poor roads they need separate condensers so that the engines were not of the atmospheric type.

Newcomen produced the first commercially viable engine building on the work of both Papin and Savery. Like those of his predecessors, Newcomen's engine was an atmospheric one. Instead of steam pressure moving the piston, the designs produced by Newcomen, Papin, and Savery relied on a vacuum created by condensing steam which allowed atmospheric pressure to move the piston.

Simply put, in Papin's design vacuum sucked the piston "down" rather than steam pushing the piston "up". This meant that the design sucked both literally and figuratively.
I haven't (yet) felt like researching some of the other points you bring up, but addressing the condensor question, i don't see how it would help in Papin's 1707 design. Given that it didn't have a piston, as such, and also that i don't see a way for steam to be exhausted and lost. Granted, that doesn't invalidate your later concerns re efficiency.


A couple of half-baked ideas that have occurred to me:

Given that Papin's 1707 didn't use crankshafts &c to transmit power, but instead used a pressure vessel to project a stream of water to hit a water-wheel (how'd he dream that up?), what if he'd used the water jet directly for water propulsion? First jet-boat, 200 years early! I seem to remember hearing something about very early experiments with water-jet propulsion, can anyone confirm that?

Papin's 1707 seems to me extremely similar in concept to a Stirling engine. I wonder what it would have taken for hime to come up with that? This one i may pursue further.
 
Top