Naval Engines - Rotate that shaft!

The history of

engines

in warships only spans a couple of centuries, a much shorter time than ships have existed, but enough time for a radical change in the field of

naval

propulsion. We've already covered boilers and the things that generate steam and more later. We'll cover propellers, the primary way of moving the ship for most powered warships, but today we're going to take a brief look at what sits between the boiler and the screw or paddlewheel to ensure the ship can move. Now, in particular, we are only going to look at the major developments of the marine engine rather than looking at every possible sub-variant and dead-end design that has ever been devised, keeping that in mind that steam

engines

have been around for about a little over a century in the 1820s, although for most of that time they had existed only as huge fixed low-pressure installations that could pump water from mines and run factories, but little else, but at the dawn of the 19th century they were They had seen several advances in elevation.

The pressure that could be used in steam engines and this in turn gave a much higher power output for a given size engine and this began to generate the idea of ​​an engine that was small and powerful enough to be used in a mobile platform rather than a somewhat more viable fixed installation due in part to the fact that well ships are simply much larger ships would be the first application of this technology; A number of experimental steamboats began to be devised in the late 18th century, but the first use of steam power in a military application was probably the paddle-driven floating battery (later Fulton), which was developed but not completed during the war of 1812 on behalf of the US Navy.

However, its nature meant that it was effectively confined to hosting the use of steam power entirely in The sea would have to wait until the deployment of ships such as HMS Comet, a paddle tug launched in 1822 along with other small ships such as the Monkey, which displaced about 210 tons and used Bolton and Watt Seam engines that had about 80 nominal horsepower. Of these engines had two cylinders and could run at perhaps one revolution every two seconds, the monkey was followed in service by the active which also had 80 nominal horsepower and then the lightning in 1823 which had 100 nominal horsepower.

These early steamboats were mainly used. for towing and general port and coastal purposes, they could not actually be called warships, all these vessels were paddle wheel powered; The limitations in terms of perceived vulnerability and the amount of space along the side that the pallets occupied would mean that a full load - on a steam-powered line-of-battle warship - would have to wait a while, but these Early ships used some of the first forms of steam engine fitted to a warship, the side lever engine, this was a step up from the simple beam. engine which was the ancestor of all other types, the side lever engine was a fairly tall mechanism, as with all steam engines, pressure built up in the cylinder, which then forced the cylinder head to rise and a Once the cylinder head reached the top of the cylinder, the steam pressure was released and, in the case of the side-lever engine, the resulting weight and vacuum caused the cylinder head to move back down, where it would repeat the cycle.

In the side lever engine, the cylinder head was connected to a rod that lifted one end of a large iron bar. lever or sometimes two for balance purposes, this would cause the other end of the lever to rise or fall in opposition and that in turn was connected through more metal elements to a crank

shaft

which generated the rotational motion compared with a beam motor where the lever was mounted. quite high on a side lever engine, the heavy levers were mounted much lower which gave the whole engine a fairly low center of gravity and made the whole thing a little shorter in the vertical element, this was important in a warship for stability. and tactical considerations, even if mounted quite low on a ship, a tall engine could end up with a substantial portion of itself above the waterline and that in turn made it very vulnerable to being disabled by artillery usually accompanied by some kind of disastrous steam. explosion that accompanied it, the side lever engine was still somewhat tall due to the cylinder size needed to obtain a useful working pressure and ships up to and including the American Civil War period sometimes ended up losing power in the hull.

The shots crippled the upper parts of their engines, but the risk was somewhat less with a side-lever engine than with other earlier engine types. The two main problems with the side stick motor were, firstly, that it could only realistically drive non-paddle wheels. It wasn't a big deal in the 1820s, but it was something that ran counter to its continued use as time went on. The other problem was that the normal twin levers and all the various connecting rods made it overall a very heavy engine for its power output. and although it ran at a somewhat higher pressure than older engines, that simply meant that the psi values ​​could be read as whole numbers above atmospheric pressure and actually did useful work beyond creating a vacuum that in the engines.

Older steam engines, especially in mine pumps, had actually ended. being what did most of the heavy lifting between the early 1820s and 1840s, an additional 70 steamships would be added to the royal navy alone, let alone all the other navies who were quite rapidly adding warships to steam and auxiliary vessels to support their forces. They were equipped with a sliding lever engine and tended to generate a steam pressure of about four pounds per square inch above normal atmospheric pressure. The radimanthus was typical of ships of this period, although it should be noted that, like many of these ships of this era, the rated horsepower was 220, but the engines could run up to around 400 indicated horsepower, almost double of the nominal.

The load on the safety valves was once again around 4 psi and the rpm when fully operational was just under 18 rpm. machinery of approximately 275 tons, which was quite a considerable mass for warships of this period, especially small ones such as the radimanthus, after the introduction of the side lever engine, a number of variants of both the older beam and as well as the sideshift engine itself, often with significant regional influences. Adoption was local to the developer who had invented it and they would occasionally see significant acceptance around the world after a short period, but most of these variants were largely civilian developments and would not appear in warship construction except in extreme circumstances such as the American Civil War. where merchant ships were taken into military service and converted into warships even though their engine design may not necessarily be optimal for a gun engagement, the main reason for the lack of use in ships actually designed for combat was that, similar to the beam engine, most of these variants were of significant weight and carried much of that weight aloft on a merchant ship, which was less of a problem thanks to the large amounts of cargo they carried and tended to have a ballast effect that would mitigate any stability problems while on warships.

They already carried quite a bit more weight than on a merchant ship due to having to carry guns and the associated gun crews and when these converted ships ended up in combat once again, these tall engines could often prove to be something of a weakness, but the The increasing prevalence of the screw propeller necessitated a new type of engine, the conversion of older ships to block ships, which were generally Napoleonic-era ships of the line, typically third rate, that had been converted to carry a machine steam and then used as guard. ship for a port or as some kind of wind-independent coastal defense force, as well as much more ambitious plans to convert larger vessels to carry auxiliary steam power plants and, of course, the construction of newly built smaller vessels saw a wide range of systems tested even though the steam locomotive had actually been a slightly later development of the steam-powered warship;

In some cases, what amounted to steam locomotives with the wheels removed were used for lower power applications and auxiliary plants, this was not ideal for several reasons, but these power plants could at least drive a propeller of screw and were quite available. Two ships in particular stand out in this period of development which lasted from approximately 1830 to 1850 AD. Powered by the HMS Elect and the French line battleship Napoleon, which was the first purpose-built steam-powered capital ship to enter service, the former Rattler used a strange type of engine that didn't really catch on in

naval

ship circles. war, the Siamese or two-cylinder engine.

It operated on the same type of lever and pivot system principle as earlier side lever engines, but instead of a single larger cylinder, it used two shorter cylinders to provide the relevant motive force, allowing the engine to be somewhat shorter in the vertical element and the two cylinders. It meant that only one arm was mounted between the two cylinders rather than the two arms more commonly found on either side of a single cylinder in a side-lever engine. It was compact and slightly lighter than the older engine, but still reflected the growing divergence. Among civilian and military engines its main attraction was the fact that it did not interfere with the lower parts of the gun casing unlike any particular fuel efficiency, but the multiple stages of lever between the engine cylinder and crank

shaft

in Any of these types were somewhat inefficient in terms of transmitting power to the screws and all that metal was quite heavy, a change was needed, so engine technology began to move towards direct drive type engines on boats. with paddle wheels that were still used as tugs, sloops and other vessels. which were not considered likely to be involved in much combat and were definitely not going to be in the line of battle one of the first direct propulsion engines was the so-called oscillating engine which was used almost exclusively to power paddle-powered warships, Simply put, the direct drive system allowed the cylinders to impart power directly to the crankshaft, making the entire system significantly lighter and more efficient than older types, as the beams and most of the rods were could be eliminated and there were fewer energy transfer stages in the system, no matter what they required. cylinders themselves could move to take account of crankshaft rotation, something that had previously been a concern of the intermediate beams, it also concentrated quite a few separate aspects of motion into a smaller number of components, which generated the savings described above but also meant that those individual fixed components were much more complex and therefore much more difficult to maintain.

The requirement for movable cylinders was a particular sticking point with this type of engine, as it also meant that the steam line feed had to be quite flexible and well if something went wrong, you had a cylinder full of hot steam that It moved back and forth, which was not so easy to approach. The other problem was that the paddle wheels only needed to

rotate

a little slower than the screws and therefore the engines had been designed for this level of rotation, this was where Napoleon comes in, although it was not the first ship in introducing the direct drive motor.

His use of one to drive a screw on a large warship raised the problem of using an engine that had a relatively low set of revolutions per minute. with a propeller that needed to go a little faster to get the boat moving at any appreciable speed, this would be solved by at least temporarily introducing another innovation to the gearing, in this case increasing the revolutions per minute, although this required an exceptionally powerful engine. . engine for that moment since, of course, each revolution of the engine had to drive several revolutions of the screw that divided the total power, hence the need for a high starting energy, so that it would remainenough per revolution to turn the propeller against the resistance of the water.

In most sea conditions, needless to say, this also required a lot of maintenance and contributed to some extent to the ship's reputation for the unreliability of her steam plant. and there, by later standards, at least very low pressures meant that a ship would burn through any reasonable coal reserve long before reaching even half of what a sailing ship could do, as they depended mainly on the amount of food in the water they carried and therefore all but the most coastal vessels would still carry a full set of sails and would continue to do so for quite some time;

In order to travel a substantial distance on steamships, steamships would have to be much larger and exploit the square cube law to increase disproportionately. its coal storage capacity, which would lead in the civilian world at least to the construction of the ss great Eastern, but given that it costs more than twice as much as two of the largest steamships of the line that can be found together and that Even though there was basically no cost involved in arming the Great Eastern, since you know she didn't really carry that much weaponry, that kind of ship size was not a viable path for warship design, no matter how generous. the budget you had. in its place, the trunk engine would be developed.

One of the ways to improve reliability was to have a longer power stroke, as this spread the force exerted on the moving components over a greater distance and therefore kept the stress on the individual components low, but this ran counter to the need for warships to keep engine levels below the waterline, so the solution that looked simple on paper but was relatively difficult to achieve in practice was put everything on its side and now you can within the confines of the boat. the dimensions have a power stroke as long as you would like, stop laughing back there without any problem from the incoming fire, since the width of the cylinder was now technically speaking the height of the cylinder, the cylinder itself could be made a little larger, this allowed the connecting rod in the cylinder.

The head oscillated within the cylinder operation and this meant that the cylinder could become fixed again instead of moving back and forth in the oscillating direct drive engine, further improving reliability capable of operating at the types of Speeds that would be necessary to drive a gearless screw propeller, powered the latest generation of wooden screw ships and would also find a home on the early HMS Warrior battleships. Another vital ship was fitted with this type of engine at first, the trunk engine was quite substantial equipment partly due to the drive for reliability and low maintenance requirements, which are key features of military engines where possible;

However, the pressures of war often led to innovation and working from a fairly solid base of engine technology in the 1850s not only did the trunk engine enter widespread service, but as a result of the War of Crimea in particular it was also possible to reduce considerably increase the working pressure and increase the speed of rotation, this was largely due to an order from the royal navy for dozens of steam gunboats whose small size required a smaller engine and to which this new engine was mass produced, which also ended up reducing the cost per unit and generated a large number of spare parts once the gunboats were stored in sheds and mostly forgotten when the Crimean War came. a closure and that in turn meant that the trunk engine, in both its large and smaller configuration, became very common in both the military and civilian world for several decades until the advancement of new technologies made them unable to compete with an even smaller variant that used two cylinders. to generate the combined power of a larger one was developed for use in American monitors during the American Civil War.

This was done solely to reduce the overall height to the absolute minimum possible, as the engines had to fit at an extremely shallow and shallow draft. American Civil War-era monitor freeboard hulls; However, the added complexity of the type for the same power output meant that they did not really see much use outside of this rather specific niche after the success of the trunk engine and other horizontally mounted engines. They were developed by companies familiar with the old style of engine building, but tended to be effectively an older engine design, usually one of the higher ones, except now only on the side, this had certain advantages in terms of common parts and reliability, but it came at the expense of efficiency.

They also tended to have considerable additional weight and lower power output due to the reintroduction of more intermediate rods and levers, as seen in older naval engines, and this meant that these engines would generally only be fitted to warships where Steam power was considered a necessary but highly auxiliary form of propulsion and therefore the cost of machinery was much more important than specific efficiency or range, so many composite gunboats, composite sloops, corvettes and Similar companies would be equipped with these types of cheaper but less efficient power plants during this period. However, another important advance in engine technology was achieved, as mentioned at the beginning.

Early steam engines used steam to drive one stroke of the engine and the vacuum left in its absence along with usually a mixture of gravity and momentum. It kept her running through the other blow, but this was also another area of ​​inefficiency and, in keeping with the growth of the steam warship, came the invention of the double-acting steam engine in which steam was fed to both ends. of the cylinder alternately depending on where the cylinder was located. The head ensured power on both the upstroke and downstroke and therefore increased overall engine power as time went on.

Ships were also becoming considerably larger and that meant there were larger engineering spaces and therefore more underwater volume and that in turn allowed the engines to run. turn to become mostly or in some cases completely vertical without compromising the durability of the ship in combat, as they would still be below the waterline also during the period from the introduction of the trunk engine to the resurgence of steam pressures vertical type. had been rising steadily from around 30 psi above the atmosphere to around 60 psi, which meant that for most ships the power available to their engines had roughly doubled, as the general principles behind steam engines equipped with cylinders were already well established in the latter part of the 19th century.

The 21st century would see the efficiency of using the energy provided by boilers increase. This followed two connected lines of development enabled by the boilers themselves becoming increasingly capable as the potential available steam pressure would double again to around 120 psi in the 1880s and by the turn of the century some cruisers would run at double or more of that again between 240 and 300 psi: firstly, the addition of multiple cylinders in full power engines rather than multiple cylinders used purely for space or stability reasons, as in the The second was the use of multiple stages of expansion, this was made possible by the aforementioned increase in the energy present in steam, although experiments with various ideas had been ongoing almost as long as warships carried steam engines.

The idea was essentially that when the steam left the cylinder at the end of the power stroke, it would normally return through a condenser and therefore return to the boilers, but it still had a certain amount of energy that could be used if the remaining energy She was tall. enough to do some kind of useful work and therefore if instead of going directly to the condenser, this steam were fed to another lower pressure cylinder which could then provide some additional force to the propeller shaft, the steam would now With much more energy removed then being able to return to the condenser, normally the first higher pressure cylinder would be smaller than the next lower pressure cylinder, which represented the final expansion of the steam and this allowed for a couple of different options when using steam in the same initial energy state as before fresh out of the boiler because it could extract more of that energy, it could increase efficiency; in fact, you could even reduce the power in the original steam feed and thus burn less fuel to some extent, since you would end up with as much power running. to the screw as with a simple expansion motor because you are extracting more from that smaller amount of energy.

Alternatively, you could increase the amount of energy in the steam leaving your boiler due to the significant excess you would get from the former. The stage would now not be wasted, yes, and could therefore go faster because it was getting significantly more power into the propeller shaft, keeping the input steam power level about the same as before, which was effectively the first option we mentioned and it was seen as something of a balance between the two with either extreme possible i.e. much higher speed or much better fuel efficiency depending on which outcome you prefer for the boat the boat was being built on. engine, for example, a torpedo boat for which speed was paramount and range was almost impossible. -The problem would want the absolute maximum power that could be obtained, whereas perhaps you would be looking for a corvette or some type of second or third class cruiser that had to travel very long distances and did not have to worry too much about maximum speed. a very efficient form of steam power plant, whereas something like a cruiser or battleship that ideally wouldn't want to go relatively fast but wouldn't want to burn through all of its fuel reserves too soon would seek a balance between the two.

It should be noted that while a double expansion engine needed at least two cylinders for obvious reasons, it was not limited to two cylinders or pairing two individual cylinders. Of course, you could do it if you wanted, but you could also, for example. It feeds two or three low pressure cylinders from a single high pressure cylinder and that is why in this era of engine technology you usually see ships described with their engines indicated as x expansion and cylinder or x cylinder and expansion to give an idea of the general configuration. The Titanic, for example, had four-cylinder triple expansion engines and the reasons you could describe the expansion as x or y is because it not only stopped a two-stage expansion with higher power output from better boilers that kept increasing, but It became possible to add a third stage to the procedures and thus the triple vertical expansion engine was born, which was the most common type of engine in the pre-retinal era, while civilian models would later develop the quadruple expansion engine.

The triple vertical expansion engine represented the end. of the line for this type of engine for warships in general, however, although they would typically be replaced in ship design during the 1900s and early 1910s, in most nations, the history of vertical engines Triple expansion was not completely finished during World War II, the vast number of smaller ones. The ships under construction and the lack of need for most of them to be especially fast and the fact that cutting turbine blades was something of a bottleneck would lead to the return of the vertical triple expansion engine in numerous ships as in anti-submarine warfare. corvettes and even some escort carriers, as it was relatively simple, cheap and easy to build and had therefore retained fairly wide circulation in the civilian mercantile world and its suppliers, where speeds above ten were rarely required. knots and, by this time, minor improvements in engine technology had allowed boats to reach just over 20 knots quite comfortably.

There was also a secondary problem: many merchant sailors were drafted into naval service and were familiar with the triple-expansion vertical engine, so they needed much less retraining if assigned to this type of vessel for most warships, although What was desired was speed and that was something the triple expansion vertical engine was beginning to have difficulty achieving as it climbed to twenty knots.higher for some of the larger cruisers and advanced in Fire control also required a much smoother ride. The fundamental problem with vertical triple expansion engines, and indeed with any engine of the types that had hitherto been used, was that a fairly large amount of metal was thrown back and forth repeatedly and at considerable speed.

In turn, it caused vibrations that could be mitigated to some extent by increased lubrication efforts as well as damping facilities, but they could not be completely eliminated and solutions that mitigated them to some extent led to a considerable increase in weight and some effects. quite interesting in the engine room as the lubricant would. They tended to swamp all the ship's engineers when the engines were running at high speed, such as in battle, until the invention of forced lubrication, which was still missing for a few years at the beginning of the 20th century. The triple expansion vertical engines could also only operate at full power. for a limited period of time before risking catastrophic failure due to repeated and rapid stress, but of all these factors as the 20th century progressed into the 1910s, vibration was the most important, as it would do quite a bit The use of long-distance rangefinders would be difficult if not impossible and that, in turn, would affect a ship's ability to fight a long-range firefight, which was now possible thanks to the development of the central director shot along with the new rangefinders, unless, of course, the expense was incurred to dampen all vibrations and therefore the steam turbine first seen in the 1890s aboard ships began to take the place of the vertical engine of Triple expansion on newly built warships.

As the first decade of the 20th century progressed, the steam turbine operated in a very different way, steam was still needed, but instead to drive linear motion in a cylinder which then had to be mechanically transformed into rotational motion. , the turbine used high-pressure steam passed through a series of rotors to directly create rotational motion, while the precise mechanism of how it did so could vary with the reaction. turbines, impulse turbines and the like, all under development, the central idea was essentially the same: they could run with minimal vibration and, because the moving parts were in simple, continuous circular motion, they could theoretically run at full power As long as it had fuel to keep the boilers firing as vertical triple-expansion cylinders, it could chain turbines to use steam at increasingly lower pressures and, as even a single turbine contained multiple rotors, it could even vary the power output of the turbine by releasing steam. of the turbine. before it completed its full journey through all the rotors or sending steam back to the turbine to increase the overall effect on the rotors themselves;

However, the turbines were more efficient in terms of using the energy contained in the steam provided to them when running at almost full power, this was great if you wanted to go very fast, it was not so good if you wanted to cruise at a slow speed. a bit more pedestrian, which was itself more efficient in terms of the amount of fuel burned in your boilers per day. The turbine efficiency per hour decreased considerably when you ran it at these lower speeds and, unfortunately, the high speed efficiency range for most early turbines was several hundred revolutions per minute, which when connected to the propellers meant a lot of cavitation and therefore damage to the propellers. and a loss of propulsive efficiency, as they simply spent most of their time spinning in a cloud of self-created bubbles and turbulence if great care was not taken with a series of different solutions were tried on some ships, especially destroyers, They simply added more propellers to the shafts, reasoning that if we could only get 50 power output from one propeller, if we put three propellers on the same shaft, then we would get 150 percent power minus a little bit.

For the weight of the additional propellers on other ships, a cruise turbine operating at lower pressure was added for low speed operations and the higher pressure turbines spinning faster would only be spooled for maximum speed operations. In some cases a cruise turbine could be completely separate installation, while in others it could be an integrated part of an overall single turbine solution, these were only interim solutions, although the real solution emerged in the 1910s with the development of turbines with gears, which worked inversely to the set of gears installed. Years earlier, on the Napoleon, that assembly had increased the rotational speed of the engine to make the screw turn at a reasonable rate, while the new gears lowered the high speed of the turbines to a much lower speed for the screws, which in turn would return the propeller speeds to their most efficient regime and also meant that there was significantly more power behind each rotation, which in turn would allow for larger, heavier propellers in the future, although it also meant that the shafts multiples would become increasingly common as it was now possible to exceed the reasonable regime. physical tolerances of the propeller shaft itself by accidentally putting too much power into it, but while reduction gear steam turbines would continue to power most warships until the end of World War II, there were two other systems that would compete with the diesel. and the turboelectric drive the turboelectric drive was the closest to the existing steam engine development line, as it actually used turbines as part of the drive train, but instead of direct drive or reduction gears to the propeller shafts, It used a turbine or turbines running constantly. at their optimally efficient speed to run electric generators, these generators would instead provide power to the electric motors as well as the rest of the ship and the electric motors would, in turn, turn the propeller shafts.

This had several advantages: the response to the need to change gear was considerably faster and the system could be put into full reverse with as much power, if not necessarily as much speed, as could be done with a fuller head if an engine or propeller was disabled by a torpedo struck by a mine or some other type of accident energy could be relatively easily redirected to other engines within their tolerances to compensate for the loss of propulsion from a survival perspective, all the engine rooms could be separated. generators and turbines and the engine rooms, as the only real connection between many of these rooms were the power cables and a blown electric motor would be much easier to repair with parts on board than a turbine that had been removed. the blades and had probably been dismantled explosively, another advantage was that if you lost one or more generators or one or more turbines, you did not necessarily lose the corresponding propeller shaft because, as with a propeller shaft that had been disabled, you would also could redistribute power from a single generator or all surviving generators and turbines it had to all propeller shafts, as long as again the amount of power that was generally available was sufficient to drive all engines, however, there were a number of problems, plus the need for two completely new and electrical systems, which meant that the motor set as a whole was quite heavy compared to a direct gear or reduction turbine set the loss of the generator if it was alone or from the generator rooms if there was more than one, it could affect the entire ship, since everything was being supplied with electrical power from these areas, the electrical systems could be much more susceptible. to impact damage than relatively solid turbines, to be fair, if an impact had reached its core machinery spaces, it would probably have bigger problems to deal with than the fact that its engines had just been taken offline, but of course , there was the other one.

The truth is that in the event of combat damage resulting in flooding, the relatively robust turbines could, and in some cases did, continue to run the propellers even as the ship slid beneath the waves, while the dangers of large amounts of electrical current possibly also included damaged cables on a steel boat that was rapidly filling with salt water did not really need any additional qualification on some boats, however it was also possible to shorten the propeller shafts. This was an advantage as the engines could simply be mounted further back in the ship, but in capital. On ships, this opportunity was limited due to the need to maintain machinery spaces within the ship's citadel, which ideally would not extend beyond the most forward turret.

Efficiency was also a topic of discussion, on the one hand, the turbine was able to run constantly at optimal speeds, which improved efficiency and compared to direct drive, the propellers also turned very efficiently; However, compared to a good set of turbines with reduction gears that also broadly allowed for this difference in rotational speed between the turbine and propeller, turboelectric propulsion could not compete simply because any energy change would go from one state to another. to another is not 100 efficient and therefore energy will always be lost in the transition in a boat with reduction gears. The energy losses from the moment the thermal energy of the steam was converted into rotational kinetic energy in the shaft are quite simple and minimal, a small amount is lost through friction and physical wear in the gear and then the energies in the screw in a turboelectric powered boat, the rotational energy is converted into electrical energy through magnetic induction in the generator, this is then transmitted with some loss due to resistance based heating in the motors wiring, which then has to reverse the process and the electrical energy is used to create an electromagnetic field which will then

rotate

the motor, resulting in the rotational kinetic energy returning again and then going to the screw.

These additional steps completely reduce the efficiency of power transmission and therefore, once a good reduction gear became affordable, the turboelectric system, for various reasons described above, was generally abandoned in warship construction to favor of geared turbine diesel engines. Completely divorced from steam production, they were instead a much more recent innovation: the internal combustion engine that did the work of a boiler turbine and, in some cases, even geared everything in a single package, its relatively compact size and The fact that they could simply be turned off and started up again in fairly short order, plus the fact that it was much harder to catch fire or explode diesel compared to gasoline, meant that they would quickly become the powerhouse favorite of submarines when they operated on the surface, but when they came to compete with the turbines of large surface warships, they were somewhat more difficult to maintain and, at least when powered by diesel fuel, which was almost as expensive to run , it was later discovered that a diesel engine could run on a fuel similar to that used in steam boilers which reduced the overall cost of operation, its main advantages were again the almost instant start compared to the hours it could take to generate steam pressure from a heated boiler and the fact that they simply burned less fuel so you could run much further with a diesel power plant than with a steam one, assuming you had the same size fuel tank, but the most critical problem for most warships it was the power density for a given volume of machinery.

The steam turbine simply gave more power than the diesel engines of the period 1900 to 1950. Now, of course, you could have a larger, heavier diesel plant to compensate for this, but this in turn would reduce the displacement available for supplies, weapons, armor and the like, all of which were quite important on warships, so on surface warships the diesel plant was not very important. often seen before the end of World War II, except in cases where autonomy was considered important enough that speed drop was not considered too big of a problem. Sometimes this would take the form of a cruising diesel, but the calculations that went into the design. of theGerman Panzerschiff class, for example, made the decision that an all-diesel powerplant was preferable simply for that range advantage, reasoning that at 28 knots there would be no capital ship, at least not among the enemies the Reichsbarino thought at the time. . of fights that could really get them, in retrospect it turned out that it was possibly not the wisest decision, but you can excuse them given the time at which the deutschland class was being designed and that completes our brief look at the various types of marine engines that were involved in the propulsion of warships from the beginning of the powered warship until the end of the period covered by the channel just after the Second World War.

Of course, there would continue to be further advances in nuclear-powered gas turbines and diesel electric propulsion in ships. diesel turbine propulsion in boats and all sorts of other wonderful and fun things, but that's for a channel that covers the latter part of the 20th century and beyond, of course, you're probably wondering now that we've covered boilers and then engines , well the next logical thing to cover is the propellers that take the output of these two mechanisms and actually push the boat through the water and you would be perfectly right so at some point in the next few months we will cover the development of the ship's propeller, that's all. for this video, thanks for watching, if you have a comment or suggestion for reviewing a boat, please let us know in the comments below, don't forget to comment on the pinned post for dry dock questions.