High consumption coal in Steam Locomotives
#21
Posted 21 November 2017 - 06:51 AM
Bye.
#22
Posted 21 November 2017 - 09:33 AM
The question was, How did you identify a steam production rate value? not how are you evaluating coal use and burn rate. There is a method of calculating steam production, but it does require that you know how long the tubes are plus the size and how many of each size.
That said, I have to return to your two screen shots and emphasise that they show incorrect control settings which is giving steam usage far higher than the boiler can produce, and it is this which is in turn leading to high coal usage.
#23
Posted 21 November 2017 - 10:50 AM
It would be better I explain the way I complete modifications of eng files.
First, in my last post, I have confused "Alt" by "Shift". Sorry.
I use Bill Hobbs "Steam Setup". I suppose you know it. It is neccesary to know the main properies of each locomotive we would model.In this case:
Boiler volume: 701.70 cu.ft.
Tubes and flues:
First tubes: number, 150; diameter: 2.17 in. Heat área: 1764.55 sq.ft.
Second tubes: number, 48; diameter: 5.24 in. Heat área: 1365.46 sq.ft.
Fire fox área: 281.48 sq.ft.
Grate área: 57.05 sq.ft.
Superheater: 1516.60 sq ft.
I adjust the eng parameters to the results obtained in the second Excel worksheet. And adapt them to news parameters of OR.
I suppose you want to study this Excel file to MSTS. Well, here it is. In this way, you will know one of the most famous spanish steam locomotives. Only a notice: Most of description parameters are in spanish. I suppose it is not a problem.
Good nigth.
Attached File(s)
-
151-3101 Santa Fé fuelizada.xls (394K)
Number of downloads: 188
#24
Posted 21 November 2017 - 01:27 PM
After starting your loco and getting up to about 60 Kmh move the reverser back from your starting setting of 71 forward to about 10-15 forward and see how your steam consumption will dramatically fall.
Another method:
Set reverser to zero.
Set throttle to FULL on. Engine should NOT move!
Now slowly move the reverser to the forward position that just gets the engine running. Probably about 20-30 but this varies.
As the engine comes up to speed, slowly move the reverser back towards the zero position just enough to maintain speed. Do not adjust throttle! Use just the reverser to control speed.
You will see a dramatic fall in steam usage.
Please note that driving with a reverser setting of 71 as you show in your pictures would get you fired for improper operation of a steamer.
A 71 reverser setting is like low gear on a truck: The higher numbers, 30 -75 are to be used ONLY for starting and and pulling a heavy load up a hill.
regards,
vince
#25
Posted 21 November 2017 - 02:16 PM
The Coal Feed Rate/Burn Rates displayed in the Loco HUD are incorrect!
I have run midneguys Frisco Mountain on Cima hill for 60 minutes of slogging at 16-20 MPH.
Feed/Burn rate --4000 to 5500 Pounds/Hour running for exactly ONE hour.
Tender Coal Usage --9863 Pounds Total in that same Hour.
I can accept that running that Loco that hard for an hour probably would use 9863 Pounds of coal!
That's all. I love steamer_ctn's Steam Locomotive Simulation code and ALL of his contributions!!
Paul
#26
Posted 21 November 2017 - 05:30 PM
farrmp, on 21 November 2017 - 02:16 PM, said:
.......................snip...............................Paul
In post #16 says he has modified his eng file. So he is modding eng file. That's okay . . . but what effect that has on the displayed steam engine data I have no idea.
As an aside, both my PRR K4's & 15 passenger runs very well at 80 mph & 12% cutoff level track.
I'd guess it would be best if the problems in the eng file are corrected first and then test.
He's pulling 780t up a 2.1% grade but it's the default Europe2! That route is well known for sloppy grade installation and not the best for testing a steamer problem.
I don't know routes but the Marias Pass v3.1 has accurate grades. There are others.
Maybe someone could suggest to the OP a better suited route for testing his steamer?
regards,
vince
#27
Posted 22 November 2017 - 01:52 AM
Vince, I agree with you that moving cut off to 71 % is a bad idea. Please, keep in mind I am testing locomotive performances after eng modifications. I did it to prove coal consumption in relation with coal reduction in tender easily. For this reason I watch with a lot of attention the feed and burn rates.
And now, I read another steamer appreciating that these two parameters are not well. This is what I mean since the beginnig of this post!
In last test I did, I was driving in 26" gradients with 100% throttle and a maximum of 60% in cut-off. Train mass was 850 metric Tons, and máximum speed 18-20 mph.
I know Chapelon advices about the best way to drive steam locomotives, and the same ones given by spanish Engineers with years of experience on the footplate. Thank you for your advices.
And well, I hope this post have been a good idea to discuss heartily amongst us; sorry, but I like comment things I think are not too much well.
Thank you again, and bye.
#28
Posted 22 November 2017 - 09:53 AM
I'll detail which of the two K4 models I use and post the results. No problem with picking out loco performance issues even if they seem small, they are an annoyance.regards, vince
edit:add test run pictures and in what is probably moot as there is this: http://www.elvastowe...omotive-tuning/
Consist Info 824.1 tons
Engine Info at Run Start
Engine Info at End of Run
After test running I'm figuring that with you tweaking your engine and the OR Team tweaking the steam code there's bound to be confusion. Not the best time for engine tuning? Maybe run some trains for enjoyment and let the code settle in for a bit. . .
Maybe you could d/l the engine I used as it is a sweet runner.
Back to pounding spikes @ Philadelphia,
vince
#29
Posted 27 November 2017 - 11:00 AM
Even if the feed figure had remained at 5000lb/hr that equates to a wee bit over one third of the total fuel in the tender for the run up the hill. 47% is considerably higher than 28%, therefore I agree that there is a big mismatch between the visible fuel feed figures and the fuel used from tender figures that needs to be investigated.
#30
Posted 27 November 2017 - 08:42 PM
copperpen, on 27 November 2017 - 11:00 AM, said:
In the HUD the FeedRate, BurnRate and Combustion values are designed to provide a representation of the coal consumption. As these are "real time" values which are constantly changing, they may not be 100% representative of the actual coal used in the long term, particularly when operating in the AI firing mode.
From an operational perspective, the amount of tender coal consumed is the critical parameter that should be considered. As suggested in my post above this will be heavily influenced by the ORTSBurnRate curve. In turn this is impacted by the steam consumption of the locomotive. What was the average steam consumption for the period that the test was undertaken for.
As part of the development of the steam locomotive tuning process, a more effective way of setting the default curve for this is being investigated.