Placement of OR specific braking parameters

[plainsman]

I was wondering where the best place in the .eng file to put the following parameters:
ORTS (
ORTSMainResChargingRate ( 0.78 )
ORTSBrakePipeChargingRate ( 19 )
ORTSBrakePipeTimeFactor ( 0.0034 )
ORTSEmergencyCausesThrottleDown ( 1 )
ORTSBrakeEmergencyTimeFactor ( 0.12 )
ORTSBrakeServiceTimeFactor ( 1.009 )
)
Should those go in the upper brake parameter section (above or below MSTS section) or in the second braking section, above or below the compressor data or below the MSTS braking data? Any ideas where to put these? I am now using them just below the compressor data, but I don't know if some of the MSTS data below these will modify or override these values?

[R. Steele]

Bob, maybe this helps a little, from section 8.6.9 Vacuum Brakes, in the manual. I'm not certain, but I think any parameter with the prefix "ORTS" will override any conflicting default MSTS data...an OR coder would have to confirm that.

Additionally the following are defined in the engine section of the ENG file:
• engine(ORTSBrakePipeChargingRate – sets the rate at which the brake pipe charges in InHg per
second (default 0.32) This value should be calculated on the basis of feeding into a 200ft^3 brake
system, as OR will adjust the value depending upon the connected volume of the brake cylinders
and brake pipe.
• engine(ORTSBrakeServiceTimeFactor – Time for lead engine brake pipe pressure to drop in seconds
(default 10.0)
• engine(ORTSBrakeEmergencyTimeFactor – Time for lead engine brake pipe pressure to drop under
emergency conditions, in seconds (default 1.0)
• engine(ORTSBrakePipeTimeFactor – Controls propagation increase time along train pipe as vacuum
increases, ie when brakes released, in seconds (default 0.02)
• engine(TrainPipeLeakRate – Rate at which the train brake pipe leaks at, in InHg per second (default
no leakage)
• engine(ORTSVacuumBrakesMainResVolume – The volume of the main vacuum brake reservoir in cubic
feet (default 110.0 , EQ operation only)
• engine(ORTSVacuumBrakesMainResMaxVacuum – The maximum vacuum in the main vacuum brake
reservoir. When this pressure is reached the exhauster will automatically stop running, in InHg.
(default 23 , EQ operation only)
• engine(ORTSVacuumBrakesExhausterRestartVacuum – pressure belowwhich the exhauster will start
to operate to recharge the main reservoir, in InHg (default 21 , EQ operation only)
• engine(ORTSVacuumBrakesMainResChargingRate – rate at which the main vacuum reservoir charges
at, in InHg per second (default 0.2, EQ operation only)
Note: It is strongly recommended that UoM be used whenever units such as InHg, etc are specificed in
the above parameters.
Other standard brake parameters such as VacuumBrakesHasVacuumPump, VacuumBrakesMinBoiler-
PressureMaxVacuum, VacuumBrakesSmallEjectorUsageRate, VacuumBrakesLargeEjectorUsageRate can
be defined as well.

[steamer_ctn]

I was wondering where the best place in the .eng file to put the following parameters:

Firstly these values are associated with the locomotive brake data, and therefore will go in the bottom section (ENG data) part of the ENG file. Secondly there is no need to have the ORTS outer brackets in the ENG file.

Refreshing myself on the code, none of these parameters will overwrite MSTS values as I don't think that they have the equivalents in MSTS.

As a general rule if there is a MSTS and ORTS parameter, the ORTS parameter will overwrite the MSTS value. For this reason if it is desired to run the stock in MSTS, it might be worthwhile to use INCLUDE files for any ORTS specific values as this will allow each simulator to use its own information.

The vacuum brakes were the subject of modification last year, and some of the enhancements included in the vacuum brakes have not been included in the air brakes. For example the application and release rates of the brakes in vacuum brakes is impacted by the train length (ie the brake system volume). Thus longer trains would take more time to release the brakes, as a greater amount of air needs to be pumped into the braking system (brake pipes, reservoirs, etc). This feature has not been included in the air brake code yet.

Some examples of coding of brakes can be found here - https://www.coalstonewcastle.com.au/physics/brakes/