[steamer_ctn]

istvanek, on 08 February 2020 - 06:56 AM, said:

Lack of documentation and explanations do not help (even for long existing features like ORTSDieselEngines Tab). I am not to blame developers as I know how huge effort they take to provide us new functions.

I have provided some documentation, and example models through my CTN site, so some information does exit, but I acknowledge that it can always be improved upon.

I believe that it would be good to establish a set of standard parameters, for example a lot of diesels have the same family of prime movers.

Finally, you do not need to be a developer to help with documentation. So non code developers could get involved and ease the load on code developers.

I would welcome a group of people to work with me to document some of OR's functions.

istvanek, on 08 February 2020 - 06:56 AM, said:

IE DieselTorqueTab often confuses the one who is trying to configure his loco trying to fill DieselEngines section and there is no explanation what it actually means and when and how this data is used during the sim. Fabric data is hardly available if any. During my research I have found that mid RPM-speed engines (so the ones used in locomotives) are constant gross HP and constant gross Torque in given RPM (it is not so at automotive market where we have high RPM-speed engines). So if engine producer data is unavailable then we can easily calculate the torque which is constant in given RPM:

This is another area that I would like investigate.

However in building/changing code it is better to focus on a small area at once. This limits changes, and helps to quickly identify any issues that may be introduced. Once I have completed the Force/Power work then I will move into the DieselTab.

Does anybody have detailed specs for the prime mover fitted to the SD70Ace?

istvanek, on 08 February 2020 - 06:56 AM, said:

But what is the impact of this tab to overall locomotive performance?

This is the first step, ie defining a benchmark (real life scenario) that we could test against.

istvanek, on 08 February 2020 - 06:56 AM, said:

And what about the other Diesel Engine Tab parameters? IE DieselPowerTab, is it used for calculations or is informative only? Running Erick GP9 I have found that engine load can be constantly over 100% in certain notches. So it seems that OR calculates net power and and wheel to rail force from other parameters independently from diesel engine power output defined by DieselEngines Tab. Does it? Or maybe it depends from engine setup (with or without Traction Tab)?

Hopefully this has been corrected in the latest unstable version.

istvanek, on 08 February 2020 - 01:54 PM, said:

Cool, this is what actually OR is doing with basic (without TE curves) eng file configuration. It constructs some kind of generic traction effort output basing on provided input data and physical calculations.

This is correct, so in my opinion, just using the "standard" Power/Force formula to calculate the motive force curve for the locomotive is simply creating more work and effort for the modeler/user without any real gain.

I think that the real value of entering a motive force table, is only achieved when an actual test or manufactures curve is plotted which does not match the "standard" formula curve.

[NickonWheels]

istvanek, on 08 February 2020 - 01:54 PM, said:

Cool, this is what actually OR is doing with basic (without TE curves) eng file configuration. It constructs some kind of generic traction effort output basing on provided input data and physical calculations.

No, it´s not. These curves are in it for better experience which maybe could only be noticed by actually running a locomotive including them. Only observing the wealth of numbers just causes misunderstanding.

One advantage of using ORTS TE curves is the starting TE changes with RPM changes and not simply by notching up/down as before, which felt very abrupt. Now we have a nice built-up of TE for more control and not bunching the couplers that hard.

[istvanek]

steamer_ctn, on 08 February 2020 - 09:07 PM, said:

I have provided some documentation, and example models through my CTN site, so some information does exit, but I acknowledge that it can always be improved upon.

I believe that it would be good to establish a set of standard parameters, for example a lot of diesels have the same family of prime movers.

Finally, you do not need to be a developer to help with documentation. So non code developers could get involved and ease the load on code developers.

I would welcome a group of people to work with me to document some of OR's functions.

I would be happy to help but please note that my English is poor. But still want to help if possible.

steamer_ctn, on 08 February 2020 - 09:07 PM, said:

This is another area that I would like investigate.

However in building/changing code it is better to focus on a small area at once. This limits changes, and helps to quickly identify any issues that may be introduced. Once I have completed the Force/Power work then I will move into the DieselTab.

OK, I understand. Take your time.

steamer_ctn, on 08 February 2020 - 09:07 PM, said:

Hopefully this has been corrected in the latest unstable version.

Seems to work well now. Thank you.

steamer_ctn, on 08 February 2020 - 09:07 PM, said:

This is correct, so in my opinion, just using the "standard" Power/Force formula to calculate the motive force curve for the locomotive is simply creating more work and effort for the modeler/user without any real gain.

I think that the real value of entering a motive force table, is only achieved when an actual test or manufactures curve is plotted which does not match the "standard" formula curve.

I agree. But I think that at some point in the future one output TE calculator would not be enough. Certain types of locomotives differs significantly (DC, AC, hydraulic transmission, mechanical transmission) so we will need different formulas for each type. Unfortunately I am full of doubts if we could get a prototypical data.

[istvanek]

NickonWheels, on 09 February 2020 - 02:07 AM, said:

No, it´s not. These curves are in it for better experience which maybe could only be noticed by actually running a locomotive including them. Only observing the wealth of numbers just causes misunderstanding.

That is cool you say that. Could you provide a prototypical data to confirm? And if so I think that there would be no problems to change (tune) OR calculations to better suit better data you provided.

NickonWheels, on 09 February 2020 - 02:07 AM, said:

One advantage of using ORTS TE curves is the starting TE changes with RPM changes and not simply by notching up/down as before, which felt very abrupt. Now we have a nice built-up of TE for more control and not bunching the couplers that hard.

Indeed, and that's a bug I think. It was not so in a previous OR versions. Maybe Peter would be able to correct that.

[NickonWheels]

istvanek, on 09 February 2020 - 03:10 AM, said:

That is cool you say that. Could you provide a prototypical data to confirm? And if so I think that there would be no problems to change (tune) OR calculations to better suit better data you provided.

Indeed, and that's a bug I think. It was not so in a previous OR versions. Maybe Peter would be able to correct that.

Maybe the only bug with the ORTS diesel locomotive model is that engines do not work with diesel engine tab but without TE curves, at least in the testing versions, but that´s no problem for me as I always use TE curves (and dynamic brake curves if needed). Of course it´s nearly impossible to get prototypical data from many locomotives, especially when talking about fantasy stuff, so such little inventions are indeed useful.

[istvanek]

NickonWheels, on 09 February 2020 - 03:42 AM, said:

Maybe the only bug with the ORTS diesel locomotive model is that engines do not work with diesel engine tab but without TE curves, at least in the testing versions, but that´s no problem for me as I always use TE curves (and dynamic brake curves if needed). Of course it´s nearly impossible to get prototypical data from many locomotives, especially when talking about fantasy stuff, so such little inventions are indeed useful.

Try last version Peter provided U2020.02.09-0406 (does he sleep? :)) The output for eng file with DieselEngines block provided and without TE curves seems reasonable and follows DieselPowerTab. Of course there is still a bug with TE increasing abruptly which need to be corrected.

I have tested TE curves you provided for GP9 and I get over 100% engine load at certain throttle positions. Assuming Erics DieselPowerTab is prototypical (and this assumption could be wrong! as I do not know if Eric was able to provide prototypical data for 16-567C prime mover) it is not good :(

Artur

[NickonWheels]

istvanek, on 09 February 2020 - 04:18 AM, said:

I have tested TE curves you provided for GP9 and I get over 100% engine load at certain throttle positions. Assuming Erics DieselPowerTab is prototypical (and this assumption could be wrong! as I do not know if Eric was able to provide prototypical data for 16-567C prime mover) it is not good :(

I don´t know about Erick´s data, but try this

DieselPowerTab ( 
0	0
325	67723.24183
388.75	222379.68351
452.5	377036.12519
516.25	531692.56687
580	686349.00855
643.75	841005.450229
707.5	995661.891909
771.25	1150318.333589
835	1304974.775269
)

[istvanek]

NickonWheels, on 09 February 2020 - 04:38 AM, said:

I don´t know about Erick´s data, but try this

I have checked - Eric provided prototypical data.

Your output data seems to overpower the engine as I get low engine loads at low throttle notches (20-30%) at speed 5-15 mph (using your TE curves).

[NickonWheels]

istvanek, on 09 February 2020 - 05:21 AM, said:

Your output data seems to overpower the engine as I get low engine loads at low throttle notches (20-30%) at speed 5-15 mph (using your TE curves).

Hmm, 25% throttle should have nearly 50% load.

[steamer_ctn]

istvanek, on 09 February 2020 - 03:05 AM, said:

I would be happy to help but please note that my English is poor. But still want to help if possible.

Sounds good.

Please send me an email via the CTN contact page.