Divide the flowers and willows, and pass through the corridor. After descending the tower, Kiyoying followed Tirpitz around Kiel Harbour and turned left and right, passing through multiple checkpoints before finally stopping in front of a room. The door groaned, the switch clicked, and a light bulb emitted a beige glow that illuminated the enclosed dark room on all sides.

"This is the design data room of the Kiel Shipyard, and whether it is adopted by the Admiralty or not, all the plans of the Keele Shipyard that have completed all the design work can be found here." Looking at Qing Ying, who was looking around at her surroundings with a surprised expression, Tirpitz smiled slightly and said, "Although Kiel is a busy port on the Baltic Sea, it is also the top shipbuilding base in Germany; The battleships independently designed by this shipyard are not inferior to those designed by Wilhelmshaven and the naval headquarters, so it is natural to take strict precautions against such a heavy place where a large amount of information is hoarded. ”

"General, is the design of the new battleship in this room?" Qingying looked at the back of Tirpitz, who was starting to rummage through the cabinets, and asked in a slightly expectant tone.

Tirpitz snorted, did not look back, but continued with the work at hand: "For a long time, the Kiel shipyard has been the top competitive customer of the Navy in foreign bidding, and the design of the four 15,000-ton decisive battle cruises that our Germany started construction in the previous two years was from the hands of the Kiel shipyard. This time, they also responded most positively to the idea of a battleship with a speed of 20 knots proposed by His Highness; After the joint laboratory led by the Admiralty solved the bottleneck of the reciprocating steam engine, they came up with three plans in a very short time for His Highness to consider. ”

"I didn't expect that the technical innovation of the reciprocating steam engine would be achieved so quickly; According to my estimates, it will be at least 1904 before a full-fledged plan can be developed. Qingying walked to the table and sat down, and there was joy in her words that could not be concealed. The reciprocating steam engine in the pre-dreadnought era was generally not efficient, and only a small part of the thermal energy output by the boiler was converted into mechanical energy; This, combined with the approximate cubic relationship between the drag and speed experienced by the battleship while sailing, makes the cost of the ship's acceleration in the pre-dreadnought era extremely staggering. The 28 first-class cruisers (8 Crowns, 6 Carresi, 4 Drake and 10 Monmouths) that Britain has built in the past six years are the most typical examples. In order to catch up with the French navy's ocean-going attack armored cruisers, which were already known for their speed, the British equipped these ships with a large number of boilers, so that the 14 ships that had been commissioned in the last three years reached a speed of 23 knots. However, the price of excessive pursuit of speed is obviously extremely staggering, the Drake class with a displacement of more than 14,000 tons is only equipped with 2 9.2-inch guns and 16 6-inch guns, and the firepower is not as good as the 9,700-ton Asama they built for Japan, and the 9,800-ton Monmouth only has 14 6-inch guns, and the firepower is simply weak!

Although the cost of increasing the speed from 18 to 20 knots was far less terrible than that of 20 to 23 knots, the German ships were certainly able to do it; However, Qingying's original intention to speed up the naval warships of the pre-dreadnought era was not simply to pursue speed, but to be able to barely keep up with the pace of dreadnoughts in the future, so as to be on the front line in the decisive battle and make up for the lack of German capital warships. If you want to increase the speed at the cost of greatly sacrificing firepower like the British, not only does it go against the original concept of decisive battle of the Qing Dynasty, but the two battleship controllers of the Kaiser and Tirpitz will not agree. Therefore, although Qingying proposed this idea more than 2 years ago, it had to be stranded due to the constraints of the power system; So much so that in the end, only 4 real battle cruises were started in 1900 and 1901, and the battleships were missed. But now, these problems have been solved along with the innovation of technology!

Tirpitz smiled and said, "Your Highness, you really underestimate my German achievements in the field of reciprocating steam engines. Whether it is the simple reciprocation in the early days or the three-swelling reciprocation that arose 12 years ago, the empire has always been in the ranks of the top techniques in the world, and in recent years, it has developed to a peak level. In addition to the Krupp hardened armor, power is the technical field of which Germany is most proud, and together with the low-freeboard and long-bow ships, it constitutes the secret of the outstanding performance of our German battleships. However, this is only a theoretical breakthrough in thermal efficiency based on the field of thermal engineering, and it will take about one and a half years to combine it with the Department of Materials and Mechanics and build a finished product. That is, the construction of such a new battleship could not be started until the middle of 1903. ”

Qingying smiled and nodded. In terms of the power choice of this class of pseudo-dreadnought warships, the reason why he gave up the steam turbine and insisted on using the three-expansion reciprocating steam engine was by no means because he did not know anything about naval power, but because there were deeper historical reasons.

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First of all, it must be admitted that from the perspective of thermal engineering and history, steam turbines are indeed more forward-looking and developmental than reciprocating steam engines. Otherwise, this kind of machine would not have completely replaced the reciprocating type in the 21st century in Qing Ying's previous life, and became the most common machine used in the entire world to convert heat energy into mechanical energy. In the field of naval power, the emergence of steam turbines is an undoubted milestone. The steam-turbine Intrepid gave her a fantastic speed of 21 knots compared to other battleships at the time, and the Invincible battlecruiser, commissioned in 1908, allowed her to soar to a terrifying 25.5 knots. These two epoch-making warships, built under the impetus of Lord Fisher, made all battleships and armored cruisers that had been or were under construction obsolete overnight, and thus entered a new era in naval history.

In comparison, the German battleships performed much worse. The Nassau-class battleships and the Blücher armoured cruisers, which they started a year later, reached speeds of only 19.5 knots and 24.25 knots, respectively, while the Caesar-class reached the same speed of 21 knots as the Dreadnought with steam turbines. Seeing this data, the vast majority of military fans think that Germany is really a typical scumbag with great ambition and talent, and low vision, and in terms of ship power, they even think that steam turbines are the best choice for the main engine of warships.

But is that really the case? The answer is absolutely no!

It is undeniable that Germany was forced to equip the Nassau class with a three-expansion reciprocating steam engine because it had no experience in manufacturing large marine steam turbines; However, Nassau's speed lagged behind that of Dreadnought, but it was definitely not because the ships were not equipped with steam turbines. Nassau's 19.5 knots is the drawing speed at the time of design, corresponding to a theoretical power of 22,000 horsepower, and at the time of sea trials, all four ships ran 26,244-28,117 horsepower of actual power, and none of them were measured at a speed below 20 knots. The real reason for the low speed of Nassau was due to the inefficiency of the propeller due to the short wet length of the exposed spindle, and by no means to the reciprocating steam engine in Germany. With a power output of 2.6-28,000 horsepower, Nassau's speed can reach the same 21 knots as the Intrepid.

Secondly, from the perspective of technology, the steam turbine does not have a huge technical advantage compared with the three-expansion reciprocating steam engine as the vast majority of military fans imagine. Although the British steam turbine has advanced concepts and great development potential, it is an out-and-out new product, and there are still many things that need to be improved; Although the German three-expansion reciprocating steam engine is relatively old, it has experienced years of development, and its technology is mature, stable and reliable, and all fields have been developed to the peak in countless practices. There is a process of gradually catching up and surpassing the old guy by replacing the old guy with new things, and it is not that Fang Fu is as awesome as Long Aotian's protagonist; In fact, under the premise of the same weight of the power system, the German power output with the reciprocating steam engine is even greater than the British power with the steam turbine!

For example, the "Indefatigable" class battlecruiser that Britain started construction in 1909. Under the condition of strong pressure ventilation, the output power of the whole power system reached 65,000 horsepower, almost exceeding the design value of 44,000 horsepower by 50%, which can be said to be a very good performance, but in terms of power weight, it is a bit miserable. The total weight of the power + auxiliary engine of this class of ships has reached 3655 tons, and the power dry weight after removing the auxiliary engine is about 3200 tons, even if it is calculated by overload power, its power-to-weight ratio is only more than 20, which is 20.3 horsepower / ton. This is the data of the construction in 1909, the use of oil-injected combustion boilers (all ships carried 840-870 tons of heavy oil) and steam turbines.

On the other hand, the Helgoland-class battleships started in Germany in 1908, although their output power is only 3.1-35,500 horsepower, which is half of the Tireless class, but the power weight of people to achieve this power is quite low. The power auxiliary of the Helgoland class is only 1,745 tons when added together, and the power dry weight after removing the auxiliary engine is only 1,200 tons at best; Even if it is calculated with 31258 horsepower, which is the smallest power in the same class, the power-to-weight ratio exceeds 26 horsepower / ton. It is important to know that Helgoland started construction one year earlier than Tireless, and it still uses a reciprocating steam engine; The fuel on the whole ship is only 3,200 tons of coal, and not even a drop of fuel oil is carried!

Therefore, the seemingly beautiful power and speed of the British battleship were actually piled up by the high power weight, and the power generated by the actual unit weight was pitiful; Although the German battleships were slow, they were still comfortable in terms of power weight with reciprocating steam engines, and could achieve speeds of 21 knots without any pressure. In this plane, the German Navy, under the guidance of Qingying, has solved the shortcomings of the low efficiency of the propeller, the speed of the battleship will return to the normal level, and the advantages of the German power system will be more significantly exerted. Even if Germany can't play with steam turbines, so what? The reciprocating power of the great virtue stick god, the steam turbine of the British stick slag, the Germans said that even if you use the reciprocating type, the output power of my same tonnage can be 30% higher than yours!