[jmlozano]

Good afternoon.
Please, think about I mean, and look screenshots.
Yes, I use a lot of steam; for this reason, boiler pressure has to decrease if we can`t produce steam enough. I agree with this.
But you can watch I have run only a few meters, in two minutes; and this is important: use of coal, is 2.8 metric tons per hour during this period of time. But... Capacity of tender has reduced 50%!we could say...16 metric tons in two minutes! Coal consumption is disagree with decrease of capacity tender.
Let me think... What have I? a coal swallower monster?
I think you are modified this parameters, because behaviour is now different, and I dare to believe not according with reality.

Bye.

[copperpen]

OK, lets take a look at your screenshots. In both of them you are using 71% forward, which if not full forward, it is not very far from it. This in itself will cause coal to be burnt at a very fast rate. What you have is like driving your car in first gear using high engine speed, then complain that you run out of petrol too fast.

Next you are working uphill with a heavy load, and over 50% of the engine brakes are applied. This adds to the coal usage figure.

Finally, your forward setting is so high that you are using steam much faster than the boiler can produce it, so the real question is, will you run out of boiler pressure before you run out of coal.

To drive a steam locomotive uphill with a heavy load in high forward gear, you must run at a much slower speed which will reduce the amount of steam used and also reduce the coal usage. Reduce the throttle setting or reduce the forward gear setting.

[steamer_ctn]

jmlozano, on 16 November 2017 - 07:26 AM, said:

Good afternoon.
Please, think about I mean, and look screenshots.
Yes, I use a lot of steam; for this reason, boiler pressure has to decrease if we can`t produce steam enough. I agree with this.
But you can watch I have run only a few meters, in two minutes; and this is important: use of coal, is 2.8 metric tons per hour during this period of time. But... Capacity of tender has reduced 50%!we could say...16 metric tons in two minutes! Coal consumption is disagree with decrease of capacity tender.
Let me think... What have I? a coal swallower monster?
I think you are modified this parameters, because behaviour is now different, and I dare to believe not according with reality.

Bye.

Can you post the ENG file for the locomotive.

Thanks

[jmlozano]

Good morning.
Here it is.
Let me point out if feed rate and burn rate are 2.8 metric tons/hour, in 2 minutes, we would wasted about 0.1 metric tons, and, for this motive, capacity tender in only the same quantity, never 16 tons. I disagree with calculation.

Thank you.

Attached File(s)

•  ESRN151F-3101.eng (34.46K)
  Number of downloads: 200

[steamer_ctn]

I have had a look at the ENG file, and have identified a couple of potential problems

i) The default combustion curve that OR uses wasn't coping with excessive steam consumption (large locomotives). I have hopefully corrected this in #3983.
It should be noted that this curve is an "average" value, and as suggested in one of my posts earlier on, the value may not suit all locomotives. For example, I suspect that the default will be low compared to the locomotive that you are modelling.

ii) The MaxTenderCoalMass ( 17636lb ) value is only equal to about 8.8 ton US, which seems to be a bit low. Some US equivalents of this loco seem to carry about 18.9 tons of coal. Is this figure correct?

Can I also suggest that you format your ENG files into sections, as it makes it easier to check if the relevant parameters are grouped and spaced for easy reading. This page gives a suggested format.

How did you identify the steam evaporation value of 59000 lb/hr (26.0t/hr)? Do you have a copy of a locomotive performance test report?

Please try #3983 and confirm that the problem has been corrected.

Thanks

[jmlozano]

Hello.
Thank you for your replay. In fact, my last eng modifications consist to divide in sections different parámeters of the locomotive performances. 151 3101 eng is one of my first studies in this field.
17,636 lbs are equivalent to 8,000 kg or 8 metric tons. In my previous messages I have had a mistake: 26 metric tons are too many tons. Sorry.
Well, I'm going to download versión you suggest. I hope commenting soon what I could appreciate.

Thank you very much again.

[jmlozano]

Good moring from Spain.
I've done my previous activity once more, to test new X3983 versión, following your suggestion.
I am going to explain the next conclusions:

1.- Route: Insbruck - St. Anon, original MSTS.
2.- Activity: Fron Imst Piztal to St. Anton.
3.- Activity start: 12:00:00
4.- End activity: 13:20:00
5.- Activity duration: 80 minutes.
6.- Maximun feed rate and burn rate, climbing towards St. Anton, 1.5 t/h. Maximun. I suppose is not an average.
I was watching this parameter all time during activity, because it's very important to compute coal consumption.
7.- If we consider maximum rate by all the activity, quantity of burn coal has been 1.5 t/h * 80 minutes activity duration, 2 tons, máximum.

8.- Coal capacity tender: 8 tons. (17636 lbs)
9.- Coal tender level at the end of activity: 40 %. Then, coal consumed: 60% * 8 tons: 4,8 tons.
10.- I suppose there is a direct relation between this last figures, coal in tender and coal consumed in according to feed and burn rate.

Well, I think something is wrong. Coal reduction in tender must be similar to coal consumption in according to feed and burn rates. But I could be in a continous mistake, sorry.

Thank you and good bye.

[steamer_ctn]

jmlozano, on 20 November 2017 - 01:43 AM, said:

Well, I think something is wrong. Coal reduction in tender must be similar to coal consumption in according to feed and burn rates. But I could be in a continous mistake, sorry.

Do you have a test report for this locomotive?

In regard to the coal usage in the tender, and the combustion rate, it is principally influenced by the ORTSBurnRate parameter in OR.

In the link above, you will notice a wide variety of burn rate curves from different test reports. OR use a single default, somewhere in the middle of these curves, and hence for locomotives on the extremities of these curves they may appear to overuse coal or underuse it. The size of the Santa Fe's coal bunker is also exacerbating the issue, as it seems to be about 50% of the size of the bunker used in the US. This may be due to the fact that distance between coaling points in Spain is shorter then in the US.

The ideal outcome would be to use combustion values from a test report for the ENG file.

Alternatively you might try increasing the curve to perhaps align with the K29 or the K4s.

[jmlozano]

Hello.
No, I have not a test report, perhaps because I don't know how I could obtain it.
I've previously studied papers of "Coals to Newcastle". I agree with you the importance of "fuel combustion" parameter. But I think would be good no forget their direct relation with "feed and burn rate", and keep in mind in programming.

Thank you very much, and... bye.

[steamer_ctn]

jmlozano, on 21 November 2017 - 01:27 AM, said:

No, I have not a test report, perhaps because I don't know how I could obtain it.

How did you identify a steam production rate value?