[Traindude]

darwins, on 01 March 2023 - 09:19 AM, said:

Also at the moment OR only models the "pop" type of safety valve. If we are going to improve safety valves, I would like to see "spring" safety valves as an alternative. In the case of spring safety valves, no matter how many openings they all normally lift at the same pressure.

So with a "sprung" safety valve, the action is gradual rather than sudden--makes sense. So for the purposes of defining the action of the safeties, the code would be something like this:

Comment (** Example code for a sprung safety valve. **)

ORTSNumSafetyValves ( 2
    ORTSSafetyValve (
       ORTSSafetyValveType ( Sprung )
       ORTSSafetyValveTriggerPressure ( 200psi )
       ORTSSafetyValveMaxSteamUsage ( x lb/hr )
    )
     ORTSSafetyValve (
       ORTSSafetyValveType ( Sprung )
       ORTSSafetyValveTriggerPressure ( 200psi )
       ORTSSafetyValveMaxSteamUsage ( x lb/hr )
    )
)

Comment (** Example code for a pop safety valve. **)

ORTSNumSafetyValves ( 2
    ORTSSafetyValve (
       ORTSSafetyValveType ( Pop )
       ORTSSafetyValveTriggerPressure ( 200psi )
       ORTSSafetyValveMaxSteamUsage ( x lb/hr )
    )
     ORTSSafetyValve (
       ORTSSafetyValveType ( Pop )
       ORTSSafetyValveTriggerPressure ( 206psi )
       ORTSSafetyValveMaxSteamUsage ( x lb/hr )
    )
)

Also, in terms of the sounds associated with sprung safety valves, it would mean a new .sms variable trigger type would need to be defined...

[Jonatan]

If we're gonna define types of safety valve, I'd also throw in the weighted valve. It works like the sprung valve but as it's a weight it had the tendency to splutter as the loco moved because of vibrations jolting the weight around. An excellent example here.

As mentioned previously, another .sms entry would be required, at current I simulate it with a stream that plays a looping sound whenever the loco moves.



It may seem like a trivial feature, but the weighted valve was fairly common on locos built in the first half of the 19th century.

[Traindude]

Jonatan, on 22 March 2023 - 08:07 AM, said:

If we're gonna define types of safety valve, I'd also throw in the weighted valve. It works like the sprung valve but as it's a weight it had the tendency to splutter as the loco moved because of vibrations jolting the weight around. An excellent example here.

As mentioned previously, another .sms entry would be required, at current I simulate it with a stream that plays a looping sound whenever the loco moves.



It may seem like a trivial feature, but the weighted valve was fairly common on locos built in the first half of the 19th century.

I see. A weighted valve has gradual opening action, but is unstable when the engine is in motion. So in that case, the example code would be:

Comment ( *** Example code for a weighted safety valves. *** )
ORTSSafetyValves ( 2
   ORTSSafetyValve(
     ORTSSafetyValveType ( Weighted )
     ORTSSafetyValveTriggerPressure ( 200psi )
     ORTSSafetyValveMaximumSteamUsage ( x lb/hr )
   )
   ORTSSafetyValve(
     ORTSSafetyValveType ( Weighted )
     ORTSSafetyValveTriggerPressure ( 200psi )
     ORTSSafetyValveMaximumSteamUsage ( x lb/hr )
   )
)

So, I believe that covers all the possible types of safeties--Pop, Sprung and Weighted. I hope I'm not missing any!

[darwins]

That looks good. Can we get someone to make it work?

[Traindude]

darwins, on 22 March 2023 - 10:14 PM, said:

That looks good. Can we get someone to make it work?

I wish I knew how to code...but I can't. Sorry.

[Aldarion]

we that do not code can help the "code-guys" by making speudo-code...
that is, using an informal language, describe how something works in what conditions, using normal syntax language in a way that helps the coder, by creating an outline or a rough draft.

[Traindude]

Revisiting the CylinderSteamExhaustFX emitters. Their puff timing is dependent on the ORTSWheelCrankAngleDifference parameter, but this is only relevant for conventional "rod engines."

In the case of geared locomotives, the CylinderSteamExhaustFX emitters should be tied to the rotation of the locomotive crankshaft instead of the wheels. And this is why:

Take for example, a Shay. The shay has a 3-cylinder steam engine connected to the crankshaft, and it stands to reason there would be 6 puffs per crankshaft rotation. However, given that the gear ratio between the crankshaft and the wheels on the trucks is anywhere from 4:1 to 6:1 (meaning it takes 4 to 6 rotations of the crankshaft to complete one rotation of the wheels), it stands to reason that there would be anywhere from 24 to 36 puffs per wheel rotation.

So in the case of geared locomotives the parameter should be ORTSCrankshaftCrankAngleDifference instead of ORTSWheelCrankAngleDifference. Who else agrees?

[Weter]

Great point.
That's obvious.

[Weter]

Hello.
With 1.5.1-411 testing version, the oddity with CylinderSteamExhaustFX have appeared:
Untill locomotive is stationary, it issues smoke (stack FX) as usual.
Just after beginning of movement, smoke disappears at all.
It doesn't recover after stop then.
Commenting-out CylinderSteamExhaustFX blocks does recover normal stack FX to working condition.

With previous testing (April 2023) during slow movement it could be seen puffs from stack, which were succeeded by normal stack FX, after speed's growth.

[steamer_ctn]

Weter, on 23 May 2023 - 09:01 AM, said:

With 1.5.1-411 testing version, the oddity with CylinderSteamExhaustFX have appeared:

Does this issue also appear in the latest Unstable version of OR?