[copperpen]

Lindsayts, on 05 September 2013 - 01:38 PM, said:

You only have half the calculation there the other half is at Line 588.....

SteamUsageLBpS = .6f * SteamUsageLBpS + .4f * speed * SteamUsageFactor * (cutoff + .07f) * (CylinderSteamDensity[CylinderPressurePSI] - CylinderSteamDensity[BackPressurePSI]);

The constants .6f and .4f are part of a smoothing function and are likley to have no real effect other than to delay any change.

As far as I can see the steamconsumption issue currently with OR is caused by the effect of the pressuredrop in the steam piping is included with the ForceFactor2 table this is causing the code to calculate the steam consumption incorrectly as although caculation actually correctly uses CylinderPressurePSI as its input but the steam piping pressure drop is included in the ForceFactor2 calculations. So the steam consumption calculations are effectively using the boiler pressure so the consumption is way to high. The data included in the my ForceFactor2 and CylinderPressureDrop code portion in the other thread should correct this issue.

Someone may wish to give this data a try, it will not blow up the world, burn down your house or make the dog start barking all night :)

Lindsay

I did after all say I have probably missed seeing where the steam usage is modified by the cut-off. Looking at the line in question we have steamusage * speed * cutoff * (forcefactor1- forcefactor2) disregarding the smoothing constants. ForceFactor1 is the positive side of the equation and ForceFactor2 is the negative side of the equation therefore ForceFactor2 cannot include the boiler to cylinder pressure drop because it is generating the back pressure which is the steam compressed on the opposite side of the piston to that which is generating the power. Looking at how the figures behave in the HUD this line is behaving as it should. which brings us back to the line which generates the initial steam usage figure.

SteamUsageFactor = 2 * NumCylinders * 3.281f * CylinderDiameterM / 2 * 3.281f * CylinderDiameterM / 2 * 3.281f * CylinderStrokeM / (2 * DriverWheelRadiusM)

I am convinced that the way this line is working is giving the high initial figures. Using the Flying Scotsman starting at Carlisle on the S&C using 52% each throttle and reverser usage outstrips generation within a few feet of starting. Using 100% throttle and 52% reverser causes usage to be double generation within one turn of the wheels.

[cjakeman]

Hi david,

dforrest, on 05 September 2013 - 03:30 PM, said:

I have installed this route and will run and document any tests required.

Thanks for the offer. I think it will be very useful,

[captain_bazza]

The translated signature is approx: "Do you have RW"

The translated body text:
"5,000 years of wind and rain accumulation would talk about how many dreams and yellow face, black faces the same smile!"

[copperpen]

I have been playing about with the steam usage line keeping the same format, but changing the float figure. It is this figure that is giving the abnormally high cylinder steam consumption. I still need to find the sweet spot but am now able to drive any steam locomotive and not exceed the steam production figure except at combined high throttle and reverser settings once the train is moving.

I also made a change to line 585 if (speed == 0 && cutoff < .5f) changing the 0.5f to 0.1f. This seems to allow lower cutoff to be used giving much finer control over the starting and low running speed for light engine and switching moves

[WaltN]

copperpen, on 05 September 2013 - 12:47 PM, said:

The problem with the default routes is that none of them are accurately modelled with regard to grades. No need to worry about an activity. Explore route will do as the requirement is to match real life performance.

Why not a test route with just straight sections? No scenery, no structures, just grades of different amounts at defined locations. Small enough for a manageable download on Elvas Tower. (Every time you place a curve on a route you downgrade the grade. This is because MSTS track sections are rigid bodies and don't climb as far as you think they do. This effect is small for gentle curves. Lay in a 90-degree curve of dynamic track, elevate it, and look at the angle on the far end. It will be horizontal, meaning level. Add another dynamic track subsection with another 90-degree curve and you'll end up at the same elevation as you started.)

And why not a test engine? Who cares what it looks like? But, it should have an elaborately instrumented cab view, akin to the steam engine simulator.

[dforrest]

WaltN, on 11 September 2013 - 08:36 AM, said:

Why not a test route with just straight sections? No scenery, no structures, just grades of different amounts at defined locations. Small enough for a manageable download on Elvas Tower. (Every time you place a curve on a route you downgrade the grade. This is because MSTS track sections are rigid bodies and don't climb as far as you think they do. This effect is small for gentle curves. Lay in a 90-degree curve of dynamic track, elevate it, and look at the angle on the far end. It will be horizontal, meaning level. Add another dynamic track subsection with another 90-degree curve and you'll end up at the same elevation as you started.)

As noted here:

Lindsayts, on 05 September 2013 - 01:44 PM, said:

Peter (Steamer_ctn) has a test route on his Coals to Newcastle web site specificly for testing OR/MSTS loco performance see

http://www.coalstone...u/physics/test/

Lindsay

David

[steamer_ctn]

Lindsayts, on 05 September 2013 - 01:44 PM, said:

Peter (Steamer_ctn) has a test route on his Coals to Newcastle web site specificly for testing OR/MSTS loco performance see

http://www.coalstone...u/physics/test/

Lindsay

I would be interested in:

i) adding to this route if there is an interest and a need for extra functionality
ii) receiving suggestions and information to be added to the Test webpage to help people to better test their stock.

Cheers

Peter

[copperpen]

steamer_ctn, on 12 September 2013 - 02:21 AM, said:

I would be interested in:

i) adding to this route if there is an interest and a need for extra functionality
ii) receiving suggestions and information to be added to the Test webpage to help people to better test their stock.

Cheers

Peter

Your test route as it stands is great for testing on grades, but probably needs maybe a couple of extra lower graded hills to climb. There were not many grades here in the UK like the two you already have. For distance testing I am using the test route from Trainsim.com that has a 15 mile oval with three short grades in the centre linked to the oval.

Mervyn

[steamer_ctn]

Hi Mervyn,

copperpen, on 13 September 2013 - 11:34 AM, said:

Your test route as it stands is great for testing on grades, but probably needs maybe a couple of extra lower graded hills to climb. There were not many grades here in the UK like the two you already have. For distance testing I am using the test route from Trainsim.com that has a 15 mile oval with three short grades in the centre linked to the oval.

What would the typical ruling gradient be in the uk?

Thanks

[copperpen]

Difficult to say. It would depend on which section of line you were on and where it was in the country. The Devon Banks are quite severe, there is Lickey, Shap, Settle & Carlisle northbound, the section north of Essendine on the East coast line, the list goes on. Still, for UK purposes, 0.5%, 0.75%, 0.95% and probably 1.25% would deal with most hard climbs. It there is also the element of distance in these climbs.