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MODIFIEDOUTBOARD
06-30-2018, 05:45 PM
Ever wonder what a real port map looks like?
Need one to run Dynomation Simulation

PPRINT
07-01-2018, 04:13 PM
You have my curiosity up.

Are you looking for port data from a sample engine?

Just port window size data, or discharge vectors? Maybe port cross section data?

Rob





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Powerabout
07-01-2018, 06:52 PM
You have my curiosity up.

Are you looking for port data from a sample engine?

Just port window size data, or discharge vectors? Maybe port cross section data?

Rob





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LA sleeve have the port dimensions but do you need a timing map?
I think there are some tools out there to convert port heights to timing maps once you add rod stroke data in to them.

zul8tr
07-02-2018, 01:31 AM
Dynomation Simulation program is for 4 strokes is that what you are working with ?

If you want info on 2 strokes port time area map in link below press "Theory" button and go to section 4. for some details on time area:

http://www.bimotion.se/

You might have seen this? Also 2 stroke port timing info here by Gordon Jennings page 76 in the book 86 in the scan list:

http://www.vintagesleds.com/library/manuals/misc/Two-stroke%20Tuner's%20Handbook.pdf

PPRINT
07-02-2018, 08:54 AM
There is a 2-stroke version of Dynomation sold by motionsoftware.


Rob



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zul8tr
07-02-2018, 10:30 AM
Since Modifiedoutboard asked "
Ever wonder what a real port map looks like? Need one to run Dynomation Simulation"
Sounds like he needs a port time or port area map for the program? Doesn't the program do that?
They are derivable with port measurements, crank degrees and piston position and rpm.

MODIFIEDOUTBOARD
07-03-2018, 02:32 PM
I haven't seen a complete port map ever posted here and wondered if nyone really has a clue as to what one liiks like. OEMs use dynomation two-stroke to design new engines. I wrote excel spreadsheet to calculate timing heights and effective area of ports. Just wonder who has ever gone behind the liner on this forum...……..

Powerabout
07-06-2018, 03:13 AM
I haven't seen a complete port map ever posted here and wondered if nyone really has a clue as to what one liiks like. OEMs use dynomation two-stroke to design new engines. I wrote excel spreadsheet to calculate timing heights and effective area of ports. Just wonder who has ever gone behind the liner on this forum...……..

I dont think there is any simulation for how efficient a port is so its just port time area

MODIFIEDOUTBOARD
07-06-2018, 05:56 AM
I dont think there is any simulation for how efficient a port is so its just port time area

Wave Simulation 8hrs later will, Empirical Formula driven wont...……..

Powerabout
07-06-2018, 07:41 AM
Wave Simulation 8hrs later will, Empirical Formula driven wont...……..
I thought you would need an airspeed to gte that to work for you?
Issue with a 2 stroke as you know is you need to keep the air speed up not just have big ports

PPRINT
07-06-2018, 10:08 AM
Dynomation requires the input of the cross sectional area of the intake and exhaust system at various locations in the port, along with their port lenghts, the crankcase compression ratio, and the dimensional details of the engine...bore, stroke, event timing, etc.

From there it calculates all of the flow/velocity numbers through the specified rpm ranges. As described above...all this number crunching takes a bit of time.

The end results is information about the engine as it progresses through the rpm range.
It is a lot of information for the user to digest and make decisions from.

In the end it only gives you data on the parameters entered. It will not design an engine for you.

That said, it is a very powerful tool in capable hands.

Rob

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MODIFIEDOUTBOARD
07-07-2018, 04:51 AM
I thought you would need an airspeed to gte that to work for you?
Issue with a 2 stroke as you know is you need to keep the air speed up not just have big ports

What does "Big Ports" mean ?
The Wave Simulation Software simulates waves in, out and thru the engine.

Powerabout
07-07-2018, 06:20 PM
What does "Big Ports" mean ?
The Wave Simulation Software simulates waves in, out and thru the engine.
ports with so much cross section the air speed is too slow unless doing 15,000rpm

MODIFIEDOUTBOARD
07-08-2018, 09:59 AM
ports with so much cross section the air speed is too slow unless doing 15,000rpm
do you have any pictures?
what is "so much" ?
Prop engines turn more than 15,000rpm...…………………..

Powerabout
07-08-2018, 06:11 PM
do you have any pictures?
what is "so much" ?
Prop engines turn more than 15,000rpm...…………………..

I am talking modified production outboards, what type are you referring?

MODIFIEDOUTBOARD
07-10-2018, 10:49 AM
I am talking modified production outboards, what type are you referring? quantify
"too wide" if you can.

Powerabout
07-10-2018, 06:00 PM
quantify
"too wide" if you can.

thats when you grind on a production engine then it wont get on the plane anymore

MODIFIEDOUTBOARD
07-12-2018, 04:47 AM
oh well guess you can't.
I don't grind I modify to purpose driven specs in order to gain performance for a specific application.

Powerabout
07-13-2018, 04:54 PM
oh well guess you can't.
I don't grind I modify to purpose driven specs in order to gain performance for a specific application.
Can you find any simulation package that is based on an outboard megaphone exhaust and or the multiply cylinders into 1 type exhaust?

MODIFIEDOUTBOARD
07-14-2018, 04:20 AM
Can you find any simulation package that is based on an outboard megaphone exhaust and or the multiply cylinders into 1 type exhaust?

Howard Richards RED can run a wave based simulation using DYNOMATION. As far as Crossflows go he has experience and at one time ran shop at Second Effort.
I would go to Looper Engine since they will outperform a crossflow...…………………..

MODIFIEDOUTBOARD
07-18-2018, 11:43 AM
Well here's part of the puzzle

PPRINT
07-18-2018, 01:34 PM
Is that out of a CAD system? Or something out of Dynomation?

Rob

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MODIFIEDOUTBOARD
07-18-2018, 02:07 PM
Chances are if you don't have patents your just a CAD Jockey...…………………….