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Simutrans Extended => Simutrans Extended Paksets => Pak128.Britain-Ex => Topic started by: ӔO on August 19, 2013, 04:02:17 AM

Title: [0.9.0] Power factor for diesels
Post by: ӔO on August 19, 2013, 04:02:17 AM
I think they could be increased slightly.

0.5 seems to be a bit low.

I would suggest they get 0.55 or 0.60, since they are already heavier than electrics and shorter on power.
Title: Re: [0.9.0] Power factor for diesels
Post by: jamespetts on August 19, 2013, 10:09:14 AM
May I ask where these figures come from? The 0.5 is intended to represent transmission losses, which, as I understand it, for diesels is a very generous figure.
Title: Re: [0.9.0] Power factor for diesels
Post by: Carl on August 19, 2013, 01:31:12 PM
I use the same stats as pak128.britain-ex for most vehicles, and my view is that 0.5 power factor is sufficient to simulate real-life performance. That said, I haven't yet incorporated the recent alterations to tractive effort, so maybe this makes a difference.
Title: Re: [0.9.0] Power factor for diesels
Post by: ӔO on August 19, 2013, 05:37:23 PM
gameplay wise, I think they can use a hint of more power.


But in real life

class 56
Engine: 3,250 bhp (2,424 kW)
at rail: 2,400 bhp (1,790 kW)
=0.74

class 58
Engine: 3,300 hp (2,460 kW)
At Rail: 2,387 hp (1,780 kW)
=0.72

Class 50
Engine: 2,500 bhp (1,864 kW)
At rail: 2,000 hp (1,491 kW)
=0.8
Title: Re: [0.9.0] Power factor for diesels
Post by: Carl on August 19, 2013, 06:46:01 PM
Yes, sorry, I should have been clear that I was only talking about DMUs. I can't speak to locomotives.
Title: Re: [0.9.0] Power factor for diesels
Post by: jamespetts on August 19, 2013, 06:47:01 PM
Thank you for that information - that is useful. What I have generally tried to do is to test the performance of the locomotives in game to see whether they match reports of real life performance of equivalent units. I have often used the High Speed Train (also known as the "InterCity 125", Class 253, Class 254 or (the individual power cars) Class 43) as a benchmark, and when I last tested it (since when the physics have not changed), it accelerated within a realistic amount of time with a realistic load. Do you think that these freight and passenger locomotives do not accelerate within a realistic time with a realistic load?
Title: Re: [0.9.0] Power factor for diesels
Post by: ӔO on August 19, 2013, 11:24:26 PM
Passenger type diesel locomotives usually have some sort of head end power (HEP) that robs even more power from the wheels.

The main problem I've found is that a pair of class 20 can't get up hills in a decent manner, compared to a single class 47, despite having more TE and hauling the same amount of freight wagons.

I can only assume that they are short on power
Title: Re: [0.9.0] Power factor for diesels
Post by: jamespetts on August 20, 2013, 12:39:07 AM
I have reduced slightly the severity of the impact of hills for the next version (on the 11.x branch): this might balance things a little better.
Title: Re: [0.9.0] Power factor for diesels
Post by: ӔO on August 20, 2013, 12:45:06 AM
okay, that should be good too :)