SUBSIM Radio Room Forums - View Single Post

Chromatix · 06-07-16, 08:26 AM

I do believe tis sort of thing has to be incorporated in the core game code to be really effective; we're talking about subtle qualitative effects as well as gross quantitative ones. If it's left to modders, then only the ships that a particular modder works on will get that modder's preferred implementation of the machinery.

However, if done well in core, it actually makes adding new ships and subs easier to add in future, since their performance characteristics tend to naturally "fall out of" a physically-based model, instead of having to be laboriously calculated and tweaked in a process that is inevitably poorly documented.

While we're on the subject, here's something you might not know about steam-powered ships: they have multiple boilers, only some of those boilers are alight and producing steam under normal cruising/patrolling conditions, and it takes a great deal of time to "light off" additional boilers when a need for increased performance is realised.

A diesel engine can be started and put on line in a matter of seconds with a well-practiced crew, but an oil-fired boiler takes several minutes at best - and as much as an hour if the crew are trying to prolong the life of the machinery by avoiding excessive heat stress.

This has implications for how enemy destroyers react when they notice your presence. If they're pottering along at cruising stations, they might have just one (of three) boilers alight for reasons of economy, giving them roughly one-third of rated engine power, corresponding to about 69% of maximum speed (again, the cube law for power against speed is in effect). A typical destroyer nominally capable of 35 knots will thus have an initial reaction speed limited to about 24 knots, and won't accelerate as rapidly to that speed as it might have done on trials. This is potentially enough of a difference to allow a submarine to dive and escape.

As for a coal-fired boiler, as many merchant ships still had in WW2... several hours can be expected to raise steam in a fresh boiler, even under favourable conditions, except for the very smallest marine engines where one hour may suffice. Most coal-fired ships used the standard "Scotch boiler", and simply fitted more of them for increased power output.

06-07-16, 08:26 AM	#5
Chromatix Watch Join Date: May 2011 Posts: 26 Downloads: 11 Uploads: 0	I do believe tis sort of thing has to be incorporated in the core game code to be really effective; we're talking about subtle qualitative effects as well as gross quantitative ones. If it's left to modders, then only the ships that a particular modder works on will get that modder's preferred implementation of the machinery. However, if done well in core, it actually makes adding new ships and subs easier to add in future, since their performance characteristics tend to naturally "fall out of" a physically-based model, instead of having to be laboriously calculated and tweaked in a process that is inevitably poorly documented. While we're on the subject, here's something you might not know about steam-powered ships: they have multiple boilers, only some of those boilers are alight and producing steam under normal cruising/patrolling conditions, and it takes a great deal of time to "light off" additional boilers when a need for increased performance is realised. A diesel engine can be started and put on line in a matter of seconds with a well-practiced crew, but an oil-fired boiler takes several minutes at best - and as much as an hour if the crew are trying to prolong the life of the machinery by avoiding excessive heat stress. This has implications for how enemy destroyers react when they notice your presence. If they're pottering along at cruising stations, they might have just one (of three) boilers alight for reasons of economy, giving them roughly one-third of rated engine power, corresponding to about 69% of maximum speed (again, the cube law for power against speed is in effect). A typical destroyer nominally capable of 35 knots will thus have an initial reaction speed limited to about 24 knots, and won't accelerate as rapidly to that speed as it might have done on trials. This is potentially enough of a difference to allow a submarine to dive and escape. As for a coal-fired boiler, as many merchant ships still had in WW2... several hours can be expected to raise steam in a fresh boiler, even under favourable conditions, except for the very smallest marine engines where one hour may suffice. Most coal-fired ships used the standard "Scotch boiler", and simply fitted more of them for increased power output.