Inboard engines and a changing world

[Adelie]

Originally Posted by newhaul

https://www.lbtechreviews.com/news/a...in-switzerland
https://euroweeklynews.com/2022/12/0...rom-its-roads/
https://www.dailymail.co.uk/news/art...shortages.html

These sources more acceptable?


https://www.google.com/search?q=swit...obile&ie=UTF-8

Choose one you want

Better, BUT....

lbtechreviews.com: ClickBait tech site.
euroweeklynews.com: Better but still middling, an English language site covering news in Spain.
dailymail.co.uk: Much better. Decent reporting, doesn't say they are banning the cars, has details on the different levels of emergency and crisis. Still based on a proposal that is 6wk old, nothing new since then.

But better than what all the outsiders think, what are the Swiss news sites saying about all this:
https://www.swissinfo.ch/eng
There's a backup power plant going on line in Feb: https://www.swissinfo.ch/eng/swiss-r...ruary/48091654
There are continuing discussions about the emergency plan: https://www.swissinfo.ch/eng/swiss-m...tages/48081126

https://www.thelocal.ch/: Not much here either way, touristy, clickbait.

https://www.nzz.ch/english: Seems to be Swiss take on major local news and international new. No discussion.

https://www.20min.ch/: In German but no apparent discussion.

https://www.blick.ch/: Ditto

https://www.watson.ch/Schweiz/: The national Swiss news section has nothing nor does the main page.


It doesn't seem to be fazing the locals that much.

Oddly enough a US car site has a decent run down.
https://www.kbb.com/car-news/no-swit...electric-cars/

My sense is that for folks living in cities, there are good public transit systems and most cities there are much more walkable than in the US so not being able to use a car is less of a problem than here.
Also, unlike the US, rural Switzerland has local bus service that covers much of the country not already covered by rail. Of course I expect most rural Swiss folk to have stuck with ICE cars for the same reasons that US rural folks have.

[Adelie]

Originally Posted by newhaul

Now to make you mad. Driest November in decades
https://www.king5.com/article/weathe...f-5d68a5381709

You would be welcome back. Friday harbor is awesome in the winter.

When I was talking to my best friend, she said it was drizzling in Seattle. Same as here oddly enough.

Friday Harbor is OK.

I prefer
Miller Bay,
Jones Island
Barlow Bay
Port Angeles
Reid Harbor
Patos Island/Active Cove
And best of all MatsMats Bay. When I die I've asked my ashes be spread there.

[newhaul]

Originally Posted by Adelie

When I was talking to my best friend, she said it was drizzling in Seattle. Same as here oddly enough.

Friday Harbor is OK.

I prefer
Miller Bay,
Jones Island
Barlow Bay
Port Angeles
Reid Harbor
Patos Island/Active Cove
And best of all MatsMats Bay. When I die I've asked my ashes be spread there.

PT Angeles no but now john Wayne in Sequim now they are close to the lavender fields

[Tedd]

Originally Posted by newhaul

But what about reanchoring when you start dragging in a hurricane.? Ice does better every time . it's energy density that is the big block and batteries can't match diesel .

I'm not talking about only having a hundred watts, I'm talking about only using a hundred watts to boost speed when motorsailing. Not at all the same thing.

But, since you brought it up, here is yet another example of an advantage of electric drives: massive power available for short duration. You can't magically increase the peak output of your diesel or gasoline engine, but that's a typical feature of an electric drive system.

Unless re-anchoring takes you hours, of course. But then I would suggest that your choice of drive isn't your biggest problem!

[pcmm]

Originally Posted by Chotu

I couldn't agree more with you. However, times are changing. Look at all the new electric only vehicles getting ready to roll out of Detroit. Ford is abandoning a lot of models and putting out electric cars and the f150 which will probably go electric soon enough.

I'm seeing boats as a forgotten point in these changes.

Electric makes no sense for driving cross country or cruising. (My opinion). Still, there are huge market shifts underway.

We rely on automotive products and fuel for our boats. These are changing at a blistering pace.

Also, lots of gas stations up for sale.

Electric will come to boating and the mass market but that is still easily a decade away. The largest problem (still) with EV's is their upfront cost. Like you mentioned there is an all electric F-150 (you can order it now) problem is its a $100k vehicle... (and its range is not great) same with all of the EV's with Ok-good range. boats have a further problem of having to push much higher displacements and traditional tankage that allows most boats to motor for days on end that is hard to match with electric propulsion. Add in electric cooking and EV-boat range is potentially further reduced.

I'm not sure most marinas have the electrical infrastructure to handle high amperage draws for charging large battery banks quickly for a large number of boats. My YC is even worse as we only have electrical infrastructure to service the boats with 15amp service (@120v)

[newhaul]

Originally Posted by pcmm

Electric will come to boating and the mass market but that is still easily a decade away. The largest problem (still) with EV's is their upfront cost. Like you mentioned there is an all electric F-150 (you can order it now) problem is its a $100k vehicle... (and its range is not great) same with all of the EV's with Ok-good range. boats have a further problem of having to push much higher displacements and traditional tankage that allows most boats to motor for days on end that is hard to match with electric propulsion. Add in electric cooking and EV-boat range is potentially further reduced.

I'm not sure most marinas have the electrical infrastructure to handle high amperage draws for charging large battery banks quickly for a large number of boats. My YC is even worse as we only have electrical infrastructure to service the boats with 15amp service (@120v)

My marina is great in that respect have several 40+ trawlers full time and untill last winter we were home port to 2 small cruise ships that do the glacier Bay run all summer 50 amp service is available at 20 of the 35 slips

[newhaul]

Originally Posted by Tedd

I'm not talking about only having a hundred watts, I'm talking about only using a hundred watts to boost speed when motorsailing. Not at all the same thing.

But, since you brought it up, here is yet another example of an advantage of electric drives: massive power available for short duration. You can't magically increase the peak output of your diesel or gasoline engine, but that's a typical feature of an electric drive system.

Unless re-anchoring takes you hours, of course. But then I would suggest that your choice of drive isn't your biggest problem!

In the midst of a hurricane your battery bank is likely somewhat depleted due to weather curtailing solar output. So you have to start a generator so may as well just keep your diesel .
With 35 gallons of fuel I can motor at hull speed for over 100 hours continuously. No way I could carry enough battery capacity for 12 hours let alone 100.

[justanotherjohn]

Keep an eye on this guy. He & his team is building an all elec sail Cat for circumnavigation.


https://elcanoworldchallenge.org/about/

[Chotu]

I think it’ll go hydrogen after seeing who is making inroads in that energy storage fields. High energy density and lightweight. Makes the most sense for all these constant power applications.

hey, I called all this when i started the thread didn’t I?

[Adelie]

Originally Posted by Chotu

I think it’ll go hydrogen after seeing who is making inroads in that energy storage fields. High energy density and lightweight. Makes the most sense for all these constant power applications.

hey, I called all this when i started the thread didn’t I?

Actually it has pretty poor energy density (MJ/l) but the best specific energy (MJ/kg) just looking at the active material.

Once you look the weight of storage containers and a fuel cell hydrogen is only somewhat better than LiFePo for both energy density and specific
Energy.

The only way hydrogen becomes a anything other than a fuel for niche uses is if:
A. Breakthrough in storage density. Hydrates are a possibility.
B. Significant improvement in fuel cell efficiency. Currently Toyota’s FC system efficiency is 48-58%. Theoretical max efficiency is about 85%. Commercial systems might get to 75%. Temperature and cell loading affect efficiency. At high loads efficiency falls way off, down to 40-45%. Low temps go the same.

[Adelie]

A tool being superior in one circumstance does not mean it is superior in all circumstances.

18.34nm/gal at hull speed of 6.46kt?
I’m not buying it.
Maybe 35hr, but not 100hr.
I could see 18-1/3mpg at 3.5-4.0kt.

[newhaul]

Originally Posted by Adelie

A tool being superior in one circumstance does not mean it is superior in all circumstances.

18.34nm/gal at hull speed of 6.46kt?
I’m not buying it.
Maybe 35hr, but not 100hr.
I could see 18-1/3mpg at 3.5-4.0kt.

Mitsubishi k2b inboard and .3gph at 3000rpm
=3 hours per gallon
35x3=105 hours at 3k rpm

[Adelie]

Originally Posted by newhaul

Mitsubishi k2b inboard and .3gph at 3000rpm
=3 hours per gallon
35x3=105 hours at 3k rpm

The Mitsubishi K2B is a 2cyl, 566cc, 12hp engine.

The Westerbeke 10 Two is a 2cyl, 27.52ci (451cc), 10hp engine. This doesn't seem to be the engine you have.
According to the curve below the very best fuel efficiency for this engine is about .455lb/hp-hr. at 2000-2500rpm. Diesel is 7lb/gal. .3gal/hr is 2.1lb/hr. 2.1gal/hr divided by .455lb/hp-hr = 4.6hp.

The Westerbeke 12D Two is a 2cyl, 38.75ci (635cc), 12hp engine. This seems closer to what you indicated you have.
According to the other curve below when the engine is using 0.3gal/hr, at just over 1800rpm the engine is putting out about 3.1hp.

I do not believe that you could get your vessel to hull speed using 3.1 or even 4.6hp.


Let's try it using your stated RPM of 3000.

At 3000rpm the max continuous output of the 10 Two is 8.5hp using 0.475lb/hp-hr. That works out to 4.0375lb/hr or 0.58gal/hr. A 35gal tank would last about 60hr at that consumption rate. At your hull speed of 6.46kt you would make it about 390nm. That's 11.1nm/gal.
I don't think you could hit hull speed on 8.5hp, a Catalina 27 sure, but that boat's 1600lb lighter and 9" shorter. I have experience with Cat-27s with a 7.5hp outboard and later a 9.9hp so I have first hand recollection. Let's say you are really making 5.8kt at 8.5hp. That means you can go 348nm on 35gal, meaning 10nm/gal.

At 3000rpm the output of the 12D-Two is 12hp and it looks like it is using 0.866gal/hr. For a 35gal tank that means you can motor at about 41hr. At 6.46kt that will take you 261nm. That seems a more reasonable.
But really Max continuous output is probably 10.5hp, let's say 10hp, which is at 2800 rpm and uses 0.71gal/hr. I could see hitting hull speed on 10hp. For a 35gal tank you'd get about 49.25hr propulsion. At 6.46kt it would take you 318nm. That's about 9.1nm/gal/


Since I have been investigating this recently, here's the secret about fixed pitch props (including folding and feathering), the propellor curve generally runs thru the worst fuel economy sections of a fuel map for most engines until you get close to max hp. MPG improves as you slow because demand falls faster than hp-hr/gal falls. At 80% rpm most engines are putting out about 1/2 of peak HP and hp-hr/gal is at about 60-70% of peak. At about 3-3.5kt is the peak mpg.

There are 2 ways to improve this:
1. Overprop the engine which you will give you peak mpg in the 4-5kt range but prevent you from hitting peak HP.
2. Or you can use a Controllable Pitch Prop (CPP) which is sort of like a continuously variable transmission, you can get much better mpg at somewhere around 2/3-3/4 of hull speed and you can still hit Max HP and max speed. In Europe where fuel has been much more expensive for a long time CPProps are fairly common on commercial vessels.

[newhaul]

Originally Posted by Adelie

The Mitsubishi K2B is a 2cyl, 566cc, 12hp engine.

The Westerbeke 10 Two is a 2cyl, 27.52ci (451cc), 10hp engine. This doesn't seem to be the engine you have.
According to the curve below the very best fuel efficiency for this engine is about .455lb/hp-hr. at 2000-2500rpm. Diesel is 7lb/gal. .3gal/hr is 2.1lb/hr. 2.1gal/hr divided by .455lb/hp-hr = 4.6hp.

The Westerbeke 12D Two is a 2cyl, 38.75ci (635cc), 12hp engine. This seems closer to what you indicated you have.
According to the other curve below when the engine is using 0.3gal/hr, at just over 1800rpm the engine is putting out about 3.1hp.

I do not believe that you could get your vessel to hull speed using 3.1 or even 4.6hp.


Let's try it using your stated RPM of 3000.

At 3000rpm the max continuous output of the 10 Two is 8.5hp using 0.475lb/hp-hr. That works out to 4.0375lb/hr or 0.58gal/hr. A 35gal tank would last about 60hr at that consumption rate. At your hull speed of 6.46kt you would make it about 390nm. That's 11.1nm/gal.
I don't think you could hit hull speed on 8.5hp, a Catalina 27 sure, but that boat's 1600lb lighter and 9" shorter. I have experience with Cat-27s with a 7.5hp outboard and later a 9.9hp so I have first hand recollection. Let's say you are really making 5.8kt at 8.5hp. That means you can go 348nm on 35gal, meaning 10nm/gal.

At 3000rpm the output of the 12D-Two is 12hp and it looks like it is using 0.866gal/hr. For a 35gal tank that means you can motor at about 41hr. At 6.46kt that will take you 261nm. That seems a more reasonable.
But really Max continuous output is probably 10.5hp, let's say 10hp, which is at 2800 rpm and uses 0.71gal/hr. I could see hitting hull speed on 10hp. For a 35gal tank you'd get about 49.25hr propulsion. At 6.46kt it would take you 318nm. That's about 9.1nm/gal/


Since I have been investigating this recently, here's the secret about fixed pitch props (including folding and feathering), the propellor curve generally runs thru the worst fuel economy sections of a fuel map for most engines until you get close to max hp. MPG improves as you slow because demand falls faster than hp-hr/gal falls. At 80% rpm most engines are putting out about 1/2 of peak HP and hp-hr/gal is at about 60-70% of peak. At about 3-3.5kt is the peak mpg.

There are 2 ways to improve this:
1. Overprop the engine which you will give you peak mpg in the 4-5kt range but prevent you from hitting peak HP.
2. Or you can use a Controllable Pitch Prop (CPP) which is sort of like a continuously variable transmission, you can get much better mpg at somewhere around 2/3-3/4 of hull speed and you can still hit Max HP and max speed. In Europe where fuel has been much more expensive for a long time CPProps are fairly common on commercial vessels.

Actually the westerbeke 10two is the mitsubishi k2b engine trust me I have 2 of them here in the yard. .
And it burns .3 gal at 3k rpm now haven't dynoed to see shp but I would assume the book is correct . The westerbeke 12d two is based on a kubota Z482 engine which is a totally different critter.

[Bowdrie]

Originally Posted by Adelie

Since I have been investigating this recently, here's the secret about fixed pitch props (including folding and feathering), the propellor curve generally runs thru the worst fuel economy sections of a fuel map for most engines until you get close to max hp. MPG improves as you slow because demand falls faster than hp-hr/gal falls.

1. Overprop the engine which you will give you peak mpg in the 4-5kt range but prevent you from hitting peak HP.

Great post.
This has been my own experience.
When my prop was overpitched, I got better mpg as long as I was willing to slow down to an easy cruise.
When I re-pitched the prop, the thrust increased for pushing into more adverse conditions and in docking/undocking/maneuvering, when quick bursts of high thrust were necessary.
And the curve of power/thrust needed starts rising pretty fast as the boat gets into the realm of wave-making resistance, (getting over a S/L ratio of ~1).