Troubleshooting ICG SW14 #1498 --- ORTSDieselEngines

[R. Steele]

Spun off from this thread (post#28) >>> https://www.trainsim.com/vbts/showth...highlight=SW14

Following recommendations given in section 8.2 pages 79-83:
1. First I removed the entire section named ORTSDieselEngines and OR loaded the engine without warnings.
2. So that proved the error was in that section
3. Restored section without exhaust portions: OR loaded with warning - using default MSTS...so forth.
4. Kept removing other lines, same result as #3 above...could not seem to find which line caused the warning.
...Read manual more closely and came across this on page 80

If the ORTS specific definition is used, each parameter is tracked and if one is missing (except in the case
of those marked with Optional), the simulation falls back to use MSTS parameters

With that in mind I simply copied the whole relevant section from the manual directly into 1498's eng file (realizing, of course, that many of the numbers would not be accurate for an SW14)

I copied over these lines from the original ORTSDieselEngines Tyler used for the SW14
1. MaximalPower
2. ExhaustColor
3. ExhaustTransientColor
4. DieselConsumptionTab
No warning in the OR log...
Looks like this:

ORTSDieselEngines ( 1
          Diesel (
          IdleRPM ( 510 )
          MaxRPM ( 1250 )
          StartingRPM ( 400 )
          StartingConfirmRPM ( 570 )
          ChangeUpRPMpS ( 50 )
          ChangeDownRPMpS ( 20 )
          RateOfChangeUpRPMpSS ( 5 )
          RateOfChangeDownRPMpSS ( 5 )
          MaximalPower ( 969.4kW )
          IdleExhaust ( 5 )
          MaxExhaust ( 3 )
	  ExhaustDynamics ( 2 )
	  ExhaustDynamicsDown ( 2 )
          ExhaustColor ( 20 6B 78 7D )
          ExhaustTransientColor( 40 21 23 24 )
          DieselPowerTab (
              0 0
              510 2000
              520 5000
              600 2000
              800 70000
              1000 100000
              1100 200000
              1200 280000
              1250 300000
          )
          DieselConsumptionTab (
               0 0
              275 3.2
              800 93.1
          )
          ThrottleRPMTab (
              0 510
              5 520
              10 600
              20 700
              50 1000
              75 1200
              100 1250
          )
          DieselTorqueTab (
              0 0
              510 25000
              1250 200000
          )
          MinOilPressure ( 40 )
          MaxOilPressure ( 90 )
          MaxTemperature ( 120 )
          Cooling ( 3 )
          TempTimeConstant ( 720 )
          OptTemperature ( 90 )
          IdleTemperature ( 70 )
     )
)

Next I changed any sections to reflect the numbers used in the original ORTSDieselEngines - NO WARNING in OR LOG!
even with the - more than likely - incorrect parameters being used for this engine.

The smoke color is too dark purple/blue for my tastes - admittedly a minor point. First time I've seen the effect of ORTS exhaust settings, nice work Tyler.

bandicam 2017-06-02 14-58-35-378.jpg
Here is the final section used in ICG SW14 1498- does not generate a warning, but probably contains numbers not suitable for a SW14.

ORTSDieselEngines ( 1
          Diesel (
          IdleRPM ( 275 )
          MaxRPM ( 800 )
          StartingRPM ( 184 )
          StartingConfirmRPM ( 316 )
          ChangeUpRPMpS ( 35 )
          ChangeDownRPMpS ( 31 )
          RateOfChangeUpRPMpSS ( 10 )
          RateOfChangeDownRPMpSS ( 5 )
          MaximalPower ( 1300Hp )
          IdleExhaust ( 1 )
          MaxExhaust ( 3 )
	  ExhaustDynamics ( 2 )
	  ExhaustDynamicsDown ( 2 )
          ExhaustColor ( 20 6B 78 7D )
          ExhaustTransientColor( 40 21 23 24 )
          DieselPowerTab (
              0 0
              510 2000
              520 5000
              600 2000
              800 70000
              1000 100000
              1100 200000
              1200 280000
              1250 300000
          )
          DieselConsumptionTab (
              0 0
              275 3.2
              800 93.1
          )
          ThrottleRPMTab (
              0 510
              5 520
              10 600
              20 700
              50 1000
              75 1200
              100 1250
          )
          DieselTorqueTab (
              0 0
              510 25000
              1250 200000
          )
          MinOilPressure ( 40 )
          MaxOilPressure ( 90 )
          MaxTemperature ( 120 )
          Cooling ( 3 )
          TempTimeConstant ( 720 )
          OptTemperature ( 90 )
          IdleTemperature ( 70 )
     )
)

Now all we need is the physics gurus among us (definitely not me - still learning) to start publishing the ORTSDieselEngines section (sec 8.2 page 81 page - Release 1.2.3706 (draft) ) for specific locos/prime movers as was done for MSTS.

I found 4 engine physics zip files in the library for Open Rails and certainly a good start was attempted, some include the following ORTS parameters:
ORTSTractionCharacteristics
ORTSCurtius_Kniffler
ORTSBearingType
ORTSDavis numbers - lacking comment section providing F2Calc inputs used to obtain the Davis numbers. Including a comment section would be most helpful...eg.

        ORTSDavis_A ( 1233.06 )
	ORTSDavis_B ( 37.0181 )
	ORTSDavis_C ( 7.705134 )
     [B]Comment( == Assumptions -Locomotive diesel/electric - speed - 65mph (105km/h), Roller Bearing, 4 axles, frontal area - 13.4m2, WagonWeight - 112.5 ton (metric), Drag 1.0 == )[/B]

Maybe if everyone pitched in we might get some correct parameters to work with. I have certainly found that when using a small selection of parameters coded specifically for ORTS there is a noticeable difference in performance in ORTS.

A big thank you to Bob Boudoin for kindly pointing the way...
If you're reading this, Bob - can you provide directions to reference works or aid in getting the ORTSDieselEngines section correct for different engines?

[tbundy1982]

Thanks for tracking down the bug, Gerry.

I omitted those additional sections because I have no idea how to calculate the proper numbers. I can fake 3 of the parameters, but I have no idea what to say about Diesel Torque. I have a feeling that a miscalculated entry here could really change the way ORTS calculates performance.

I like the additional ORTS stuff that you've added. I'll remember to add a comment line for friction next time. The only difference I think between my original Fcalc friction parameters and yours is that these engines could not travel faster than 45 mph without damaging the traction motors. I think that is an across-the-board restriction with these AAR switcher trucks, even when dead-in-tow. I remember reading somewhere that the gearing design did not allow for higher-speed regearing. The lesson was that if you tore up the gears, it was an exceptional PITA to repair them due to the design. The Flexicoil switcher trucks were good for 65 mph.

Tyler

[R. Steele]

Thanks for tracking down the bug, Gerry.

I omitted those additional sections because I have no idea how to calculate the proper numbers. I can fake 3 of the parameters, but I have no idea what to say about Diesel Torque. I have a feeling that a miscalculated entry here could really change the way ORTS calculates performance.

I like the additional ORTS stuff that you've added. I'll remember to add a comment line for friction next time. The only difference I think between my original Fcalc friction parameters and yours is that these engines could not travel faster than 45 mph without damaging the traction motors. I think that is an across-the-board restriction with these AAR switcher trucks, even when dead-in-tow. I remember reading somewhere that the gearing design did not allow for higher-speed regearing. The lesson was that if you tore up the gears, it was an exceptional PITA to repair them due to the design. The Flexicoil switcher trucks were good for 65 mph.
Tyler

Hi, Tyler...Agree with you, not knowing specifically what numbers to plug into all these ORTS parameters IAPITA! IMHO the OR development team should include a commentary on each of these lines...referencing where to look for data, how to use the data to calculate the desired parameter and how set up the tables. Ideally, there should be a master ORTSDieselEngines for each type of locomotive in use...starting with the old defaults - Dash9, SD40, and GP38. As you explained in another post, modifications done by individual roads to update or repair equipment could then be taken into consideration (like bumping up the MaxPower for the SW14's to 1300Hp).

Regarding using 65mph (105kph) as a basis for the Davis Numbers**. Here's how it was explained to me, (best as I can remember, not word for word). Any speed under 65mph does not markedly change the Davis numbers (if at all) --- it is above 65mph (105kph) that the Davis numbers really begin to make a difference. I'll try to find the original discussion to be more accurate.
So the ORTS Davis numbers calculated at 65mph (105kph) are useful for all operating speeds - and are considered to provide more accurate performance with OR coding than the MSTS friction numbers (which apparently no one really knows how they are used by MSTS)
**Take a look at the graphs under View in F2Calcfor Diesel or Electric Locomotives.

To prove this to myself - using F2Calc and recalculating the numbers at 72kph (45mph) provides the same result.
bandicam 2017-06-04 13-26-06-042.jpg

The ORTS Curtius Kniffler adhesion parameter also provides more accurate performance in OR than the MSTS Adheasion (sic) parameter, which also is a bit of a puzzle to people.

Bob Boudoin has ORTSTractionCharacteristics for C36-7's in v5_10orc33_c36physics.zip. I've used them for the Diesels West ATSF C36-7s and they make a difference. (as an aside... I just finished converting ALL of my DW equipment, 387 eng & 446 wag files - no ORTSDieselEngines section because I do not know enough to accurately determine what to use! cripes.)

A comment section for the ORTS Davis numbers would certainly save much time and effort down the line. Also would help folks learn how to calculate such numbers and the reasoning behind the calculations.

Thanks for taking the time and effort to make the SW14's...I'm having a good time learning how to solve some of the wrinkles in the ORTS parameters.