[WAD] sub charging issue

[JPFisher55]

S120 is running at full at periscope depth to recharge battery. It says it is recharging. However, the battery level is lower in test2 than 1.
But test 2 is later in time.

[ComDev]

At full throttle, the battery drain rate is higher than recharge rate. It takes 4 hrs to empty the battery, and 8 hrs to recharge it.

Is this different in the sim than in RL?

Thanks [8D]

[JPFisher55]

I thought that when you are running on diesel then you are recharging the batteries from the diesel engines. So the faster the diesel engine runs, then the faster the battery recharges. But what do I know? I'll use cruise speed instead. Thank you for the answer.

[thewood1]

I am not an expert on submarine propulsion, but I know engines and energy storage. Theoretically you are right. Running the engine faster charges batteries faster...if the engine is doing nothing else. If the engine is also driving propulsion at near its capacity, that is energy not going to the battery or any other type of storage.

[JPFisher55]

Also, maybe the subs have to use both diesel and battery engines to go full speed at periscope depth. Using cruise or creep speed eliminated the issue and are recharging the batteries.

[ComDev]

The submarine is Diesel-Electric, not Diesel/Electric. Diesel/Electric submarines had the shaft directly connected to the diesels, but this setup has not been in use since early WW2 or thereabout.

Modern subs only use the diesels to recharge the battery. The shaft is connected to the electric motor. When in use, the diesels run at full power regardless of electric motor throttle settings. As such, the batteries will take 8 hours to recharge at creep speed where drainage is at its minimum. At higher throttle settings, recharging will take longer. At full or flank speed, you will use more electric power than the diesels can produce.

The same goes for AIP. See 1.11 release notes for details.

Thanks [8D]

[JPFisher55]

Thanks for the info, Emsoy.

[Luidzi]

May I suggest an user interface change to inform that the sub uses more than one fuel source at one time? For example highlight both diesel and battery when snorkeling at speed higher than cruise (same with battery and AIP if the AIP system is active at speed higher than creep), or change the wording of status. Until I read this thread, I wondered why my sub runs out of battery at periscope depth, when the highlighted fuel was diesel and status was underway (recharging batteries).