Proposal to Improve Historical Accuracy of Engine Techs

[BattleshipOfDestruction]

This topic is to discuss an improvement to the generic and immersion breaking engines types in the game. More topics will be coming about other modules and discussions on their accuracy and possible improvements that can be made.

There are a lot of nonsensical engines here in the Vanilla Options. Quadruple Expansion Engines were used on Merchant vessels, particularly liners, but not on warships. Turbines were used instead. Additionally, Gas Turbines were not invented until the 1960s at least, making their inclusion into the engine options here very anachronistic.

At Tier I we have 3-Cylinder Triple Expansion Engines (Steam 3x3Exp). Introduced in 1890 and Obsolete in 1910 (In Game), Triple Expansion engines were rather commonplace around this time. It is a balance between power and efficiency. It consisted in its basic form of 3 cylinders. One cylinder on high pressure, one using medium pressure and the final one using low pressure for the best use of Steam Pressure. At the Time, most boilers could only handle up to 150 psi working pressure which limited the speed at which a ship could move without more boilers and more engines for more shafts.

Preliminary Values:

- Engine Vibrations: 50%

- Engine Weight: -50%

- Engine Cost Per Weight: 25%

- Fuel Efficiency: 25%

-Boiler Weight: 0%

-% of Top Speed for Cruising Speed: 50%

-Maintenance Cost: -50%

-Engine Damage Chance (From Penetrations): 0%

-Ship Repairs (Engines): 0%

-Acceleration: 0%

-HP Per Engine Ton: 18

-Ship Flaws: 0%

 

At Tier II we have Semi-Diesel Hot Bulb Engines (Semi-Diesel). Introduced in 1890 and available until 1900 (In Game), They were the predecessor to the first type of diesel engine. They were developed in the early 1890s by the British Engineer Herbert Akroyd Stuart and were called Hot Bulb Engines. His design utilized a compression ignition design which was one of the concepts upon which the Diesel Engine would be based. These engines used Heavy Fuel Oil as a fuel using a separate vaporizing combustion chamber. This design was later improved by German Immigrants Mietz and Weiss who combined the hot-bulb engine design of Stuart with the two-stroke scavenging principle of Joseph Day to provide nearly twice the power compared to a four stroke engine of the same size. It was not frequently used beyond small vessels for their main powerplant due to its limited horsepower and it was prone to failure.

Preliminary Values:

- Engine Vibrations: 25%

- Engine Weight: -105%

- Engine Cost Per Weight: 5%

- Fuel Efficiency: -10%

-Boiler Weight: -100%

-% of Top Speed for Cruising Speed: 50%

-Maintenance Cost: 75%

-Engine Damage Chance (From Penetrations): -25%

-Ship Repairs (Engines): 25%

-Acceleration: 5%

-HP Per Engine Ton: 4

-Ship Flaws: 5%

 

At Tier III we have 4-Cylinder Triple Expansion Engines (Steam 4x3Exp). Introduced in 1895 and available until 1910 (in game), an extra Low Pressure cylinder was added to the expansion engine using 2 more fire tube boilers per engine or two less water tube boilers to support the higher working pressure needed to drive this engine. This increased torque which in turn increased the horspower by around double while increasing the fuel efficiency.

Preliminary Values:

- Engine Vibrations: 75%

- Engine Weight: -25%

- Engine Cost Per Weight: 50%

- Fuel Efficiency: 25%

-Boiler Weight: 0%

-% of Top Speed for Cruising Speed: 60%

-Maintenance Cost: -25%

-Engine Damage Chance (From Penetrations): 0%

-Ship Repairs (Engines): 0%

-Acceleration: 10%

-HP Per Engine Ton: 25

-Ship Flaws: 0.5%

 

At Tier IV we have First Generation Marine Diesel Engines (Diesel I). Introduced in 1896 and available until 1900 (in game), the First Generation of Marine Diesels was put forward in concept by Rudolf Diesel in 1892. The first functional engine, the Motor 250/400, was built in 1896. With an efficiency of 26% it revolutionized marine engines due to its high compression ratio which allowed for this high efficiency and power output. It still was only a marginal improvement in horsepower per ton over the Hot Bulb Engine and therefore was deemed underpowered except for small auxillary vessels and river going merchant tankers. Like its predecessor, it suffered from mechanical problems. The example shown here is of a similar type used on the Russian Tanker Vandal in 1903 which was the first ship powered by a diesel engine and carried electric steering.

Preliminary Values:

- Engine Vibrations: 15%

- Engine Weight: -75%

- Engine Cost Per Weight: 10%

- Fuel Efficiency: 0%

-Boiler Weight: -100%

-% of Top Speed for Cruising Speed: 55%

-Maintenance Cost: 50%

-Engine Damage Chance (From Penetrations): -30%

-Ship Repairs (Engines): 50%

-Acceleration: 15%

-HP Per Engine Ton: 6

-Ship Flaws: 3%

 

At Tier V we have Steam Turbines (Turbines). Introduced in 1895 and Available until 1920 (in game) Steam Turbines were a natural step forward for Naval Planners considering the marginal improvement for the less space efficient Quadruple Expansion Engines that were adopted for merchantmen at the time. Turbines are space efficient compared the previous engine types and can provide more efficient power to weight ratios than previously available. This early model is direct drive which is less fuel efficient than later turbines, especially at low power, but more responsive.

Preliminary Values:

- Engine Vibrations: 10%

- Engine Weight: -5%

- Engine Cost Per Weight: 100%

- Fuel Efficiency: 10%

-Boiler Weight: 50%

-% of Top Speed for Cruising Speed: 70%

-Maintenance Cost: 0%

-Engine Damage Chance (From Penetrations): -25%

-Ship Repairs (Engines): 5%

-Acceleration: 25%

-HP Per Engine Ton: 50

-Ship Flaws: 1%

 

At Tier VI we have Second Generation Marine Diesels (Diesel II). Introduced in 1912 and available until 1920 (in game) the Second Generation of Marine Diesels were developed by M.A.N. Diesel which provided Military Grade Marine Diesels for the First Time. They were primarily used in U-Boats/Submarines and Torpedo Boats in World War I as anything larger would be prohibitively expensive due to the high maintenance costs of the engines as they still suffered from semi-frequent bouts of mechanical breakdown.

Preliminary Values:

- Engine Vibrations: 10%

- Engine Weight: -100%

- Engine Cost Per Weight: 15%

- Fuel Efficiency: 25%

-Boiler Weight: -100%

-% of Top Speed for Cruising Speed: 60%

-Maintenance Cost: 40%

-Engine Damage Chance (From Penetrations): -50%

-Ship Repairs (Engines): 75%

-Acceleration: 50%

-HP Per Engine Ton: 60

-Ship Flaws: 2.5%

 

At Tier VII we have Reduction Geared Steam Turbines (G. Turbines I). Introduced in 1915 and available until 1925 (in game) a reduction gearbox was added to steam turbines to increase the power and efficiency. Heavy and expensive, it was the only way to get higher efficiency and more fine control over ship speed.

Preliminary Values:

- Engine Vibrations: 25%

- Engine Weight: 0%

- Engine Cost Per Weight: 150%

- Fuel Efficiency: 25%

-Boiler Weight: 25%

-% of Top Speed for Cruising Speed: 75%

-Maintenance Cost: 50%

-Engine Damage Chance (From Penetrations): -30%

-Ship Repairs (Engines): 15%

-Acceleration: 40%

-HP Per Engine Ton: 60

-Ship Flaws: 1.5%

 

At Tier VIII we have the Turbo-Electric Drive (Turbo-Electr.) Introduced in 1915 and available to 1930 (in game) the Turbo-Electric Powerplant was a uniquely American Design. The Turbo-Electric Drive combined the advantages of Steam Turbines with powerful Electric Engines powered by batteries for use in large vessels. It utilized the Steam turbines being turned at its most efficient RPM at all times to save on fuel, while storing excess energy not needed for its systems in Batteries located in the bilges of a ship. Comparatively expensive and also around the same weight as Geared Turbines, they were able to allow the ship to move faster than most other systems of the time for unparalleled fuel efficiency.

Preliminary Values:

- Engine Vibrations: 50%

- Engine Weight: 25%

- Engine Cost Per Weight: 200%

- Fuel Efficiency: 60%

-Boiler Weight: 50%

-% of Top Speed for Cruising Speed: 90%

-Maintenance Cost: 75%

-Engine Damage Chance (From Penetrations): -40%

-Ship Repairs (Engines): 50%

-Acceleration: 75%

-HP Per Engine Ton: 70

-Ship Flaws: 5%

 

At Tier IX we have Double Reduction Geared Turbines (G. Turbines II). Introduced in 1925 and available until 1950 (in game), they incorporate a second set of gears and using lighter materals to improve the weight of the gearbox to make them lighter than earlier systems. This allows these turbines to be much more fuel efficient, cost effective and reliable than existing Diesel and previous powerplants.

Preliminary Values:

- Engine Vibrations: 10%

- Engine Weight: -15%

- Engine Cost Per Weight: 150%

- Fuel Efficiency: 75%

-Boiler Weight: 25%

-% of Top Speed for Cruising Speed: 80%

-Maintenance Cost: 25%

-Engine Damage Chance (From Penetrations): -40%

-Ship Repairs (Engines): 25%

-Acceleration: 60%

-HP Per Engine Ton: 125

-Ship Flaws: 1%

 

At Tier X we have the Third Generation of Marine Diesels (Diesel III). Introduced in 1930 and available until 1950 (in game), it was still lead in the industry by M.A.N. Diesel. This example sported an addition of Superchargers and Inter-coolers which resulted in a increase in horsepower per ton, which was then installed in their Type VII U-Boat, the Workhorse of the Kriegsmarine. This Diesel Engine was decidedly more reliable than the World War I example due to better manufacturing tolerances, better control surfaces and the increased power did make it viable as an option for destroyers and perhaps light cruisers. It did not, however make it good enough for Heavy Cruisers or Battleships/Battlecruisers as they were considered too temperamental to install. If one were to be installed, it would be difficult to service or replace once the armor had been added.

Preliminary Values:

- Engine Vibrations: 5%

- Engine Weight: -125%

- Engine Cost Per Weight: 25%

- Fuel Efficiency: 50%

-Boiler Weight: -100%

-% of Top Speed for Cruising Speed: 70%

-Maintenance Cost: 30%

-Engine Damage Chance (From Penetrations): -75%

-Ship Repairs (Engines): 100%

-Acceleration: 60%

-HP Per Engine Ton: 80

-Ship Flaws: 2%

 

At Tier XI we have Fourth Generation of Marine Diesels (Diesel IV). Introduced in 1935 and available until 1950 (in game), M.A.N. Diesel was contracted to build a new engine for the new long range Type IX U-Boat. It was so impressive that the Deutchesland Class Heavy Cruiser, was the first of its kind to be equipped with engines similar to this. Although they still were a headache to maintain and replace if completely destroyed, they were overall more reliable than previous engine designs at a better horsepower  to ton ratio and much higher fuel efficiency.

Preliminary Values:

- Engine Vibrations: 5%

- Engine Weight: -115%

- Engine Cost Per Weight: 50%

- Fuel Efficiency: 80%

-Boiler Weight: -100%

-% of Top Speed for Cruising Speed: 75%

-Maintenance Cost: 25%

-Engine Damage Chance (From Penetrations): -80%

-Ship Repairs (Engines): 125%

-Acceleration: 80%

-HP Per Engine Ton: 120

-Ship Flaws: 1%

[justMike247]

an interesting and well written body of work.. Nicely done Sir...

 

Only critique I'd venture... re battle damage to any form of steam driven propulsion. If a shell penetrates into either boiler rooms or engine rooms, that 0% damage is gonna be sorely tested. Uncontrolled release of superheated hi pressure steam into engineering spaces = near instantaneous loss of skilled personel.

[BattleshipOfDestruction]

On 10/5/2024 at 1:45 PM, justMike247 said:

an interesting and well written body of work.. Nicely done Sir...

 

Only critique I'd venture... re battle damage to any form of steam driven propulsion. If a shell penetrates into either boiler rooms or engine rooms, that 0% damage is gonna be sorely tested. Uncontrolled release of superheated hi pressure steam into engineering spaces = near instantaneous loss of skilled personel.

Yes, as I said this was preliminary values and were only meant as guidelines. When we get to other topics; notably explosive and propellant technologies, the damage and other boosts were calculated based upon the explosive power relative to TNT which are taken from various declassified sources of military papers. I also have a section on the complete rebalancing of the various cannons, their penetrations (based on an average of all real historical examples from all major nations in game) and damage using a specific formulae used to approximate a TNT normalized damage value relative to the average amount of filler in the shell.

[justMike247]

18 hours ago, BattleshipOfDestruction said:

When we get to other topics; notably explosive and propellant technologies, the damage and other boosts were calculated based upon the explosive power relative to TNT which are taken from various declassified sources of military papers.

See... teasin a guy by flauntin information like that... oughta be laws against that stuff... I've been looking for sources of that specific info for... *le cough* decades...

 

I look forward to your subsequent posts...