ORTS Standard Engine Files

**R. Steele** · 05-16-2019, 11:30

Originally posted by =FI=Ghost

This is what I have in my Table:

GE ES44AC High Adhesion (GE GEVO-12; 4700 GHP)
a. Starting tractive effort of 198,000 lbs (880.8 kN) up to 7.519 mph.
b. Traction horsepower at wheel is 4,390 hp (3,276.12 kW); efficiency rating of 93.4%.
c. Max Dynamic Brake effort of 117,000 lbs (520.442 kN) from 16.51 mph to 3 mph; linear fade from that speed to 0 lbs @ 1 mph.
d. Dynamic Brake horsepower at wheel is 5,145.6 hp (3,840 kW).
e. Increased weight of 195.954 metric tons (432,000.1884 lbs).
f. Maximum speed of 75 mph.
g. Fuel consumption @ notch 8 is 210 gallons per hour.

Izvor:

http://railworksamerica.com/forum/vi...p?f=30&t=12693

We have essentially the same mass 432000lbs...so using the same Adhesion as the ES44AC ( indeed the AH may be higher, but not less ) we have a STE of 206064lbs...not 198000lbs.

Looking over the railworks site you referenced I believe the difference lies in the adhesion values I am using vs. the ones on the railworks site.

ES44AC for OR

Mass 415130.4lbs, Adhesion=47.7% STE 198017lbs

Railworks ES44AC physics

Mass 416,008.02lbs, Adhesion=43.268% STE 17999835.00936 ( 180000lbs )

We have agreement on the AC44AH mass - 432,000.1884 lbs - we just need to determine what adhesion to use.

Finding the real value is something beyond my skill set and I suspect that of most people outside of an actual electrical/mechanical engineer employed by the builder...as the definition of Adhesion is:

Adhesion = Coefficient of friction x Locomotive adhesion variable

The friction coefficient between wheel and rail is usually in the range of .40 to .45 for relatively clean, dry rail in reasonable condition and is essentially the same for all locomotives. The locomotive adhesion variable represents the ability of the locomotive to convert the available friction into usable friction at the wheel rail interface. It varies dramatically from about .45 for old DC units to about .90 for modern AC units. This variable incorporates many factors including electrical design, control systems, truck type and wheel conditions.

We can agree on the coefficient of friction as you see above, but knowing the Locomotive adhesion variable?? -- I have never seen that published...I don't think outside of the manufacturer that is considered useful knowledge. I've never found the actual forumla with the variables defined for finding the locomotive adhesion variable.

After all that hot air.... What Adhesion do you think is reasonable for the ES44AH?
Looking over everything...I'm wondering if an adhesion of 47.7% is high for the ES44AC, what do you think?
Any other opinions...Bob, Derek are you guys around?

**=FI=Ghost** · 05-16-2019, 14:17

These are the official specifications given in the ES44AC brochure by GE. It seems that the adhesion value of 43.268% gives a number closer to the one in the specs.

ES44ACspecs.jpg

**R. Steele** · 05-16-2019, 15:32

Originally posted by =FI=Ghost

These are the official specifications given in the ES44AC brochure by GE. It seems that the adhesion value of 43.268% gives a number closer to the one in the specs.

[ATTACH=CONFIG]76861[/ATTACH]

Borislav, thank you for the specs. I reworked everything, trying to account for inconsistencies and here is what I arrived at, look okay?
Still, I'm left with a couple of questions...maybe someone who reads the thread will provide some insight.

GE ES44AC and ES44AH Specifications

1. ES44AC
Mass: 415130.4lbs
Adhesion: 43.268%
STE: 179618.62lbs
CTE: 145000lbs
Gross HP: 4500
Traction HP: 4365
Max Speed: 75mph
Max Dynamic Braking Effort: 98000lbs

2. ES44AH
Mass: 432000lbs
Adhesion: 46.296%
STE: 199998.72lbs
CTE: 166000lbs
Gross HP: 4500
Traction HP: 4365
Max Speed: 75mph
Max Dynamic Braking Effort: 98000lbs

These specs differ from the railworks ones in that:
1. Dynamic braking effort is lower 98000lbs ( per mfg spec ) vs 117000lbs
2. Gross HP is 4500 ( per mfg spec ) vs 4700HP (railworks)
3. ...and the railworks braking HP is 5145.6 -- higher than the actual gross HP of the primer mover...is that actually possible?

Regards, Gerry

**derekmorton** · 05-16-2019, 15:45

1. ES44AC
Mass: 415130.4lbs
Adhesion: 43.268%
STE: 179618.62lbs
CTE: 145000lbs
Gross HP: 4500
Traction HP: 4365
Max Speed: 75mph
Max Dynamic Braking Effort: 98000lbs

From your post:-
These are AC4400 figures.

These are the ES44AC figures that I have

ES44AC
Mass: 420000lb
Adhesion: ?
STE: 198000lb
CTE: 165000lb
Gross HP: 4520
Traction HP: 4390
Max speed: 75mph
Max Dynamic: 110000lb

Both sets of figures above confirmed with BB's figures.

**=FI=Ghost** · 05-16-2019, 16:55

Adhesion should be a little higher in ES44AH models, due to their increased weight compared to standard ES44AC models (but I may be completely wrong on this one, as I am a psychologist, and not an engineer).

With that in mind, 46.296% for AH models seems just right.

The differences compared to those at the railworks site probably come due to different sources used for input data. While I was doing research for my Locomotive Specification Table, I often found different values for Mass/STE/CTE, or even HP/KW, for a certain model of locomotive. I even read how some real world train engineers testified that factory given specifications sometimes didn't match the specifications they came up with during testing and measurements.

All in all, whenever I had official specification charts (like I did with Evolution Series locomotives), I used those. The most important thing for me was the standardization of my locomotive fleet, which was the reason behind creating the Locomotive Specification Table in the first place.

**R. Steele** · 05-16-2019, 18:24

Regarding the SD40-2 HP discrepancies in the Open Rails locomotive HUD

I did some tests and found this...which confirms all other tests I've done.

All testing done on my standard test route...Peter Newells Coals to New Castle Test Route.
http://www.coalstonewcastle.com.au/physics/route/

First Test: using the SD40-2 Std_eng file rated at 3140HP Gross, with ORTS Max Tractive Curves...same results are obtained...less than 3000HP, with load at 76.2%. Power to the rails is at 2397HP (I'm assuming this is power to the rails, because 2397HP divided by 3140HP = 0.76337 -- close enough) The SD40-2 has a locomotive eff. of 83% ....approx. 6% higher)

1st Test=3140HP_Std_eng+MaxTractive Curves.jpg

Second test: Increased Gross HP to 3925, enough to make a noticeable difference --- Now you will notice that power to the rail has remained approximately the same --2363HP ( the longer you run the test, it stabilizes at a slightly higher value) and the right side HP (rated Gross HP) shows 3925HP. The Load now reads 60.2%. ( 2362 divided by 3925 = 0.60203).
Now this proves two things:
1. Running power reading is coming from the MaximalPower line and probably also the DieselPowerTab of the ORTS DieselEngine Block
(which was increased for this test from 3140HP to 3925HP)
...and
2. Power to the rail did not increase -- The load percentage would have to decrease, which it did.

2nd Test=OR_Std_Eng+3925HP+MaxTractive.jpg

Third Test: Restored SD40-2 Std_Eng file Gross HP to 3140 and removed the ORTS Max Tractive Curve set. With this result.
1. Running power restored to gross HP of 3140
2. Load percentage up to 93.6% ( now 10% higher than SD40-2 locomotive efficiency of 83% )
3. Power to the Rail is now at 2946 - almost 3000HP.
3rd Test=No_Max_Tractive_Curves.jpg

Conclusion. The advanced adhesion model does not correctly implement the ORTS Max Tractive Curve Set.

Questions: Could my conclusion be wrong? Could I be constructing the curve set incorrectly? ..you betcha... Although the formula I'm using is recognized and used to find this type of traction effort. And the tractive curves do prove out when tested, they provide more reliable traction in the simulation. Although the power to the rails does not match what one would expect.
There has been a suggestion to allow the ORTS curve sets when using the simple adhesion model.

Any thoughts anyone? Any ideas? Light bulbs go on?
Regards, Gerry

**derekmorton** · 05-16-2019, 23:38

The sd70 exhibits the same issue?

I am running the simple adhesion model.

**R. Steele** · 05-18-2019, 12:45

Originally posted by derekmorton

The sd70 exhibits the same issue?

I am running the simple adhesion model.

Derek, my default is advanced adhesion. But you bring up an interesting point...so I'm going to make some test runs using the simple adhesion model.

**R. Steele** · 05-29-2019, 08:37

An Error was found in the files: Eagle eyed Derek Morton spotted a duplicate ORTSMaxTractiveForceCurves line the "Std_Eng_SD45.inc" file.

Code:

MaxForce ( 428752 )
MaxContinuousForce ( 365301.3 )
ORTSMaxTractiveForceCurves (
ORTSMaxTractiveForceCurves (					
		0 (

This should provoke a warning or error in the OR log. Just remove the extra line...apologies, I missed this one.

Tip-O-Hat to Derek.

**R. Steele** · 09-02-2019, 15:03

Sometime this fall, there will be an update to the OR_Std_Eng set uploaded on 4-30-1019 ( orts_standard_engines.zip ).
The first set contained 176 standard engine files for use in Open Rails. The update will have approximately 221, updating the original 176 and adding 45 more.

Making up the new additions is a set of 5 eng files for use in BHP mine service, standard engine files for a Krauss-Maffei ML-4000 and a NW2, and others, new and old.

The primary reason for the update is threefold:
1. To find and correct errors I missed the first time around, and to recheck the whole set for correct values and consistency.

2. To improve the DieselTorque Tab -- the first set gave torque in foot-pound, which as it turns out OR does not support. OR reads the Torque tab as Newton Meters -- N.m -- so the results ( numerically ) are much lower than realistically expected. The new files provide the correct torque values in N.m.
Please see this thread for a more complete explanation: ( also you'll find out what the torque tab is used for in Open Rails )
http://www.elvastower.com/forums/ind...om-for-torque/

3. To provide internally consistent and correct MaximalPower values for the Standard Engine files.
In the OR Diesel Engine definition ( manual sec 8.2.1 "ORTS Specific Diesel Engine Definition" ) there is a parameter with the name "MaximalPower". It's been established that this value refers to "Power at the Shaft" of the prime mover, what is commonly referred to as "Gross Power". Now it's relatively easy to find the traction hp of a locomotive --- that's what MSTS used for "MaxPower" --- and it is normally published in operator manuals and other documents. Not so easy to find is the Gross Power. If it can be found at all, it's usually tucked away in a test report...dense reading to find it.

However, if you know the Traction HP and also have a reliable value for the locomotive efficiency you can calculate the Gross HP of a diesel engine.
Traction HP divided-by Efficiency equals Gross Horsepower
Thanks to Bob Boudoins work, reliable values for both can be determined. Also I found some test reports that provided good data.
Result --- the new files will contain revised MaximalPower values, which also affects torque. As accurate as I can make them at this point.

Gross hp minus Traction hp represents a power loss. ( subtract that loss from 100% and you have the locomotives efficiency in converting gross power ( power at the shaft ) to traction power.

Please see this thread for a good graph of locomotive power losses:
http://www.elvastower.com/forums/ind...e-performance/

Here's a sample of the new files:

Code:

Comment ( Standard ORTS Diesel Engine for GE AC4400CW, CW44AC )
Comment ( Data from Bob Boudoin Engine physics )
Comment ( ORTSCurtius_Kniffler ( 6.672 25.0872 0.161 0.7 ) )
Comment ( Performance Ratings == Gross HP 4824 == Traction HP 4390 == CTE 145002lb @ 10.2mph==91.0%eff. == STE 177555lb )
Comment ( Mass 417776lbs = 189.5t == metric, Adhesion Factor = 42.5% )
Comment ( MassÃ—Adhesion Factor = Starting Tractive Effort )
Comment ( Traction HP divided-by Efficiency equals Gross Horsepower )
Comment ( include ( "..\\..\\Common.inc\\Locomotives\\Std_Eng_AC4400CW_bb.inc" ) )

ORTSDieselEngines ( 1			
	Diesel(		
	IdleRPM	( 315 )	
	MaxRPM	( 1050 )	
	StartingRPM	( 215 )	
	StartingConfirmRPM	( 365 )	
	ChangeUpRPMpS	( 92 )	
	ChangeDownRPMpS	( 58 )	
	RateOfChangeUpRPMpSS	( 34 )	
	RateOfChangeDownRPMpSS	( 23 )	
	MaximalPower	( 3597387 )	
	IdleExhaust	( 1.2 )	
	MaxExhaust	( 2.2 )	
	ExhaustDynamics	( 1.6 )	
	ExhaustDynamicsDown	( 0.8 )	
	ExhaustColor	( 20161819 )	
	ExhaustTransientColor	( 40212324 )	
	DieselPowerTab (		
		0	0
		407	449673
		499	899347
		591	1349020
		683	1798694
		775	2248367
		867	2698041
		959	3147714
		1050 3597387
	)		
	DieselConsumptionTab (		
		0	0
		315	13.6
		1050 798.6
	)		
	ThrottleRPMTab (		
		0	315
		12.5	407
		25	499
		37.5	591
		50	683
		62.5	775
		75	867
		87.5	959
		100	1050
	)		
	DieselTorqueTab (		
		0	0
		315	109050
		1050 32715
	)		
	MinOilPressure	( 30 )	
	MaxOilPressure	( 90 )	
	MaxTemperature	( 120 )	
	Cooling	( 3 )	
	TempTimeConstant	( 720 )	
	OptTemperature	( 75 )	
	IdleTemperature	( 55 )	
	)		
)
ORTS (
	ORTSEmergencyCausesThrottleDown ( 1 )
	ORTSWheelSlipCausesThrottleDown ( 1 )
	)
	ORTSMainResChargingRate ( 0.4 )
	ORTSBrakePipeChargingRate ( 200 )
	ORTSEngineBrakeReleaseRate ( 38 )
	ORTSEngineBrakeApplicationRate ( 34 )
	ORTSBrakePipeTimeFactor ( 0.003 )
	ORTSBrakeEmergencyTimeFactor ( 0.1 )
	ORTSBrakeServiceTimeFactor ( 1.009 )
	TrainPipeLeakRate ( 0.0833 )
	TrainBrakesControllerMaxReleaseRate ( 10 )

MaxForce ( 790508 )
MaxContinuousForce ( 645001 )
ORTSMaxTractiveForceCurves (					
		0 (			
			0	0	
			3.72	0	
			5.36	0	
			7.15	0	
			8.94	0	
			10.73	0	
			15.20	0	
			19.67	0	
			24.14	0	
			28.61	0	
			33.08	0	)
	0.125 (				
			0	98814	
			3.72	98814	
			5.36	68522	
			7.15	51392	
			8.94	41113	
			10.73	34261	
			15.20	24184	
			19.67	18688	
			24.14	15227	
			28.61	12848	
			33.08	11112	)
	0.25 (				
			0	197627	
			3.72	197627	
			5.36	137045	
			7.15	102783	
			8.94	82227	
			10.73	68522	
			15.20	48369	
			19.67	37376	
			24.14	30454	
			28.61	25696	
			33.08	22223	)
	0.375 (				
			0	296441	
			3.72	296441	
			5.36	205567	
			7.15	154175	
			8.94	123340	
			10.73	102783	
			15.20	72553	
			19.67	56064	
			24.14	45682	
			28.61	38544	
			33.08	33335	)
	0.50 (				
			0	395254	
			3.72	395254	
			5.36	274089	
			7.15	205567	
			8.94	164453	
			10.73	137045	
			15.20	96737	
			19.67	74752	
			24.14	60909	
			28.61	51392	
			33.08	44447	)
	0.625 (				
			0	494068	
			3.72	494068	
			5.36	342611	
			7.15	256958	
			8.94	205567	
			10.73	171306	
			15.20	120922	
			19.67	93439	
			24.14	76136	
			28.61	64240	
			33.08	55559	)
	0.75 (				
			0	592881	
			3.72	592881	
			5.36	411134	
			7.15	308350	
			8.94	246680	
			10.73	205567	
			15.20	145106	
			19.67	112127	
			24.14	91363	
			28.61	77088	
			33.08	66670	)
	0.875 (				
			0	691695	
			3.72	691695	
			5.36	479656	
			7.15	359742	
			8.94	287793	
			10.73	239828	
			15.20	169290	
			19.67	130815	
			24.14	106590	
			28.61	89935	
			33.08	77782	)
	1.0 (				
			0	790508	
			3.72	790508	
			5.36	548178	
			7.15	411134	
			8.94	328907	
			10.73	274089	
			15.20	193475	
			19.67	149503	
			24.14	121817	
			28.61	102783	
			33.08	88894	)
		)

**R. Steele** · 09-02-2019, 15:41

Whoops, left out part of the math for a statement I made below:

Gross hp minus Traction hp represents a power loss. ( subtract that loss from 100% and you have the locomotives efficiency in converting gross power ( power at the shaft ) to traction power.

Should read:
Gross hp minus Traction hp represents a power loss. Divide that power loss by the Gross HP and you get a percentage of loss, substract that from 100% and you arrive at the Locomotive Efficiency.

4545 (Grosshp) - 4000 ( Tractionhp) = 545hp.
545/4545 = 0.1199119911991199 ( rounded off to 0.12 or 12% )
100% - 12% = 88% locomotive efficiency.

**=FI=Ghost** · 09-03-2019, 06:16

Wonderful news! I am looking forward to this new release.

**=FI=Ghost** · 09-26-2019, 04:01

Have you got any news regarding these new engine files, mate?

**R. Steele** · 09-26-2019, 10:56

Yep, I have completed 100 so far, looks like the total will be around 225. I'm finding errors that I made ( data mistakes, typos, etc. ) that neither myself nor anyone else spotted...so, in the case of bad data, the errors have to be researched, corrected, and verified...takes time. The Alco's have slowed me down, Bob Boudoin has some information, but accurate Alco data - especially for the FA series -- is difficult to find. With certain locomotives I just have to stop --- realizing I'm not going to get it more accurate at this point.

I know you are interested in the ES44AH --- the new completed file...with expanded Torque Tab is below.

I still have questions about the actual gross output power ( power at the shaft of diesel engine = MaximalPower in ORTS engine definition ) for many of these models...I know that some of the values I have calculated are reasonable...about others...I have doubts....but the method I've adopted for now gives some internal consistency to the data...obviously as I learn more --- revisions will be in order.

Code:

Comment ( Standard ORTS Diesel Engine for GE ES44AH == Heavy, software enhanced CTE and adhesion control )
Comment ( ORTSCurtius_Kniffler ( 6.418 20.505 0.161 0.7 ) )
Comment ( Performance Ratings == Gross HP 4729 == Traction HP 4445 == CTE 182624lb @ 9.01mph==94.0%eff. == STE 204768lb )
Comment ( Mass 432000lbs = 195.952t == metric, Adhesion Factor = 47.4% )
Comment ( MassÃ—Adhesion Factor = Starting Tractive Effort )
Comment ( Traction Horsepower divided-by Efficiency equals Gross Horsepower )
Comment ( include ( "..\\..\\Common.inc\\Locomotives\\Std_Eng_ES44AH_195-952t.inc" ) )

ORTSDieselEngines ( 1
	Diesel (		
	IdleRPM ( 315 )		
	MaxRPM ( 1050 )		
	StartingRPM ( 215 )
	StartingConfirmRPM ( 365 )		
	ChangeUpRPMps ( 92 )
	ChangeDownRPMps ( 58 )		
	RateOfChangeUpRPMpSS ( 34 )		
	RateOfChangeDownRPMpSS ( 23 )		
	MaximalPower ( 3526415W )		
	IdleExhaust ( 1.2 )		
	MaxExhaust ( 2.2 )		
	ExhaustDynamics ( 1.6 )		
	ExhaustDynamicsDown ( 0.8 )		
	ExhaustColor ( 20161819 )		
	ExhaustTransientColor ( 40212324 )		
	DieselPowerTab (		
		0	0
		407	440709
		499	881417
		591	1322126
		683	1763581
		775	2204289
		867	2644998
		959	3085707
		1050 3526415
	)		
	DieselConsumptionTab (		
		0	0
		315	12.8
		1050 750.7
	)		
	ThrottleRPMTab (		
		0	315
		12.5	407
		25	499
		37.5	591
		50	683
		62.5	775
		75	867
		87.5	959
		100	1050
	)		
	DieselTorqueTab (		
		0	0
		315	106899
		407	82735
		499	67481
		591	56976
		683	49302
		775	43449
		867	38839
		959	35113
		1050 32070
	)		
	MinOilPressure ( 30psi )		
	MaxOilPressure ( 90psi )
	MaxTemperature ( 120degc )		
	Cooling ( 3 )		
	TempTimeConstant ( 720 )		
	OptTemperature ( 75degc )		
	IdleTemperature ( 55degc )		
	)		
)			
ORTS (
	ORTSEmergencyCausesThrottleDown ( 1 )
	ORTSWheelSlipCausesThrottleDown ( 1 )
	)
	ORTSMainResChargingRate ( 0.4 )
	ORTSBrakePipeChargingRate ( 200 )
	ORTSEngineBrakeReleaseRate ( 38 )
	ORTSEngineBrakeApplicationRate ( 34 )
	ORTSBrakePipeTimeFactor ( 0.003 )
	ORTSBrakeEmergencyTimeFactor ( 0.1 )
	ORTSBrakeServiceTimeFactor ( 1.009 )
	TrainPipeLeakRate ( 0.0833 )
	TrainBrakesControllerMaxReleaseRate ( 10 )

MaxForce ( 911478N )
MaxContinuousForce ( 812352N )
ORTSMaxTractiveForceCurves (					
		0 (			
			0	0	
			3.59	0	
			5.36	0	
			7.15	0	
			8.94	0	
			11.18	0	
			15.65	0	
			20.12	0	
			24.59	0	
			29.06	0	
			33.53	0	)
	0.125 (				
			0	114104	
			3.59	114104	
			5.36	76360	
			7.15	57270	
			8.94	45816	
			11.18	36653	
			15.65	26181	
			20.12	20363	
			24.59	16661	
			29.06	14098	
			33.53	12218	)
	0.25 (				
			0	228015	
			3.59	228015	
			5.36	152591	
			7.15	114444	
			8.94	91555	
			11.18	73244	
			15.65	52317	
			20.12	40691	
			24.59	33293	
			29.06	28171	
			33.53	24415	)
	0.375 (				
			0	341925	
			3.59	341925	
			5.36	228822	
			7.15	171617	
			8.94	137294	
			11.18	109835	
			15.65	78454	
			20.12	61020	
			24.59	49925	
			29.06	42245	
			33.53	36612	)
	0.50 (				
			0	455836	
			3.59	455836	
			5.36	305053	
			7.15	228790	
			8.94	183032	
			11.18	146426	
			15.65	104590	
			20.12	81348	
			24.59	66557	
			29.06	56318	
			33.53	48809	)
	0.625 (				
			0	569746	
			3.59	569746	
			5.36	381284	
			7.15	285963	
			8.94	228771	
			11.18	183017	
			15.65	130726	
			20.12	101676	
			24.59	83190	
			29.06	70391	
			33.53	61006	)
	0.75 (				
			0	683657	
			3.59	683657	
			5.36	457515	
			7.15	343136	
			8.94	274509	
			11.18	219607	
			15.65	156863	
			20.12	122004	
			24.59	99822	
			29.06	84465	
			33.53	73203	)
	0.875 (				
			0	797568	
			3.59	797568	
			5.36	533746	
			7.15	400309	
			8.94	320248	
			11.18	256198	
			15.65	182999	
			20.12	142333	
			24.59	116454	
			29.06	98538	
			33.53	85400	)
	1.0 (				
			0	911478	
			3.59	911478	
			5.36	609977	
			7.15	457483	
			8.94	365986	
			11.18	292789	
			15.65	209135	
			20.12	162661	
			24.59	133086	
			29.06	112611	
			33.53	97597	)
		)

Regards, Gerry

Postscript: If anyone has good data about the RPMs for any diesel locomotive, please PM me...I've redesigned my ORTS Diesel engine spreadsheets to produce Throttle RPM tab with Idle and Notch1 having the same RPMs...also I have the ability to enter customized RPM ranges....up to this point hardly any of these Std_Eng files have prototypical RPM tabs...they work and give reasonable results...but accuracy is lacking.

**ebnertra000** · 09-26-2019, 12:25

I'm away from home, but I do have RPM data for early dash 8s (which should work for Super 7s, too). I could look through some of the other manuals I've found, too