ORTS Standard Engine Files - Version 2

[R. Steele]

Just uploaded Version 2 of the Standard Engine files...these are meant to replace the include files found in "orts_standard_engines.zip". Took about 6 months longer than I expected, kept finding and receiving new sources of information.
Here are the changes in version two:
1. Expanded Comments Section
2. Diesel Consumption tab expanded for some engines
3. Throttle Rpm tab more accurate
4. Diesel Torque Tab Expanded and corrected
5. Units of Measure added where appropriate
6. ORTS brake parameters expanded
7. ORTS Max Tractive Curves refined for more prototypical curve form.
8. 71 additional engine files added

Found good data about diesel consumption here:

http://www.gatx.com/wps/wcm/connect/d6109c4a-a86a-4d37-a0b4-a2d61a49f34f/Fuel_Consumption_Chart.pdf?MOD=AJPERES&CVID=kBD-GwT

Also took some effort, searching, and asking those who know about accurate rpm settings. Hopefully the Throttle RPM tab is now more accurate for most engines. ( lots of careful reading of manuals )

In the course of reworking the files I kept finding more locomotives that interested me, so I kept adding new ones -- finally ended up adding 71 additional engine files...some are just different weights ( every road seemed to have their specific weight requirements ). Other new additions are not in the version one files. ( grand total 247 standard engine files )

Most importantly version two gave me a chance to refine the ORTS Max Traction curves. I was never really satisfied with the curves for version one. I realized how I could "shape" the curves to a more prototypical curve form after I had found and examined five good traction curves from as many different diesel locomotives. Certainly it would be preferable to have actual curves for all 247...but that is just not possible. So knowing what the prototypical curve shape looks like allows one to produce a reasonable set of working curves for any locomotive, especially if you also have accurate values for Starting Tractive effort and Continuous Tractive effort.

See the curves illustrations below...the plotted curve is from a British Railways Performance and Efficiency Test report for a 3300hp Co-Co "Deltic" diesel electric locomotive. ( thanks to Peter Newell for a copy of the report )
Compare the test curve with similiar data points on the calculated curve set from the spreadsheet I am using.
Test curves at 50mph = 20,000lbs
OR curves at 50mph = 19,700lbs

Test curves at 40mph = 25,000lbs
OR curves at 40mph = 24,500lbs
Similiar comparisons can be found at other points along both curves.
I have seen very accurate calculated curves ( for example from Joe Realmuto ) - but I am not at that level of mathematical skill or knowledge of diesel locomotive physics to be able to construct such curves. Best I can do at this point.
ORTS Calculated Curves bandicam 2020-03-11 18-06-12-429.jpg
Test Report Curves bandicam 2020-03-11 18-03-01-411.jpg

[derekmorton]

Many thanks, Gerry

[Heruraha93]

yes thank you this is interesting - with tractive force does it decrease with speed like this always regardless of how gradually one increases speed? - i am guessing the answer might be in the manual, hopefully in laymans terms

[derekmorton]

First question: yes, it does always decrease with speed over the speed of maximum tractive effort.

second question: It won't be in the manual.

The diesel engine puts out a maximum value of power.

Very simply

Power is generated when a force is applied at a set speed. Power= force x speed

If you double the force, you double the power.

[=FI=Ghost]

This is what I have been waiting for!! Thank you very, very, very much!!!

[cn bala]

Have a question for you, Gerry. I wonder if the files in ver. 2 have Trainsimulations CN GP40-2LW series locomotives? I don't know if you have that route, CN Ruel Subdivision in your Open Rails program. Just asking to see if you work on these locomotives above.

Thank you,

John

[R. Steele]

Regarding cn bala's question more generally ... If I have the time and am supplied with ( or can find ) accurate data I will try to work up OR Standard Engine files on request --- provided --- I have the time, and the request is reasonable...both items are my decision.
Just PM me, or use email found in Boilerplate.doc supplied with download.

For those interested in trying their hands at understanding traction effort and what goes into curves expressing traction effort, here's a paper to read ( or wade through --- as the case may be --- I don't mind wading or swimming in deep waters myself, from time-to-time. )
https://www.researchgate.net/publica...ing_Locomotive

Also has information on Curtius Kniffler and other assorted mind bending data.
head-spinning.jpg

[trainmanaustin]

Downloaded and installed!

[qballbandit]

Gerry, just getting around to applying these. Many thanks for your time and effort spent putting this together for the community.

[klsc85]

Gerry, I second everyone's kudos on your work. What an amazing task you've taken on, one all of us can benefit from.

Uncle E

[R. Steele]

Thanks to all, I enjoy doing them...I've already found some things in them that need correcting and also have added 3 new engines. Update and add-on packages will come sometime in the following months.

[R. Steele]

There have been some questions about the brake parameters in the files being faster than prototypical or those used in MSTS...Yes they are.
Excerpt from the ORTS Parameters Block.odt doc included with the files:

Referring to this: ( positioned in the engine section of the ENG file )

ORTSEmergencyCausesThrottleDown ( 0 )
ORTSWheelSlipCausesThrottleDown ( 0 )
ORTSMainResChargingRate ( 0.4psi/s )
ORTSBrakePipeChargingRate ( 200psi/s )
ORTSEngineBrakeReleaseRate ( 38psi/s )
ORTSEngineBrakeApplicationRate ( 34psi/s )
ORTSBrakePipeTimeFactor ( 0.003 )
ORTSBrakeEmergencyTimeFactor ( 0.1 )
ORTSBrakeServiceTimeFactor ( 1.009 )
ORTSAirBrakeMainresvolume ( 28.35ft^3 )
TrainPipeLeakRate ( 0.0833psi/s )
TrainBrakesControllerMaxReleaseRate ( 10psi/s )

These parameters operate faster than prototypical locomotive brakes.

**Note especially the "ORTSBrakePipeChargingRate" value of 200psi/s -- this is considerably faster than prototypical rates. 20psi/s to 60psi/s would probably be closer to actual rates.
Please change to satisfy your own preferences.
Feedback, is much appreciated.

I have not devoted the time I should to learning about brakes and the proper values for OR...these do work in OR, but are faster than normal.
There are definite differences in braking parameters between 1st Gen locomotives, locomotives in the 60's-80's and the most modern diesel locomotives. There are members of the forum that know much more about these parameters than I do. Perhaps, they will post some of there observations and advice.

The best I can do right now to address the issue is to refer to this pdf doc which was posted at Elvas, from Joe Realmuto:
http://www.elvastower.com/forums/ind...ended-braking/

If you cannot access the document at Elvas, please PM me with your email address and I will provide a copy. Adjusting the eng brake parameters is something for Ver3 or the update packages.

[=FI=Ghost]

Being one of those guys, I can only say thank you once again for your efforts!

[R. Steele]

A problem with Std_Eng_ET44C4.inc has been reported. When the file is incorporated into the MSTS engine file ( ENG section ) this error can cause the locomotive to not appear in OR. However, if the file is used in the OpenRails folder there appears to be no problem...the error is an extra bracket in the comments section.

Here's the line with extra bracket highlighted. The highlighted bracket should be removed.

Comment ( Mass 416000lbs = 188.694t == metric, Adhesion Factor = 34.61% ) )