Experiments and evolution
In the world of tank building, the use of high-speed diesel engines for tanks became the gold standard only in the late 50s. NATO countries realized that it was time to get rid of gasoline power plants much later than the Soviet Union, but quickly caught up. Domestic tank engine building in the post-war period was based on the proven V-2 concept, which had gone through fire, water and copper pipes over the previous decade.
During the Great Patriotic War, the leading role in the modernization of the B-2 was played by the serial design bureau # 75 in Chelyabinsk. In "Tankograd" during the war years, a huge engine-building complex was formed, tuned exclusively for the production of diesel engines of the V-2 series. On the one hand, this made it possible to seriously save on the large-scale production of motors, and on the other hand, it created difficulties in re-profiling the site. In the book "Tank Engines (From the History of Tank Building)" E. A. Zubov in this regard even gives calculations on the costs of development work of small foreign manufacturers and industrial giants. On average, a small company gets a return on every dollar invested 24 times more than, say, the giant Ford or General Motors. In the Soviet Union, there was an overwhelming majority of large engine-building plants, which led to a certain conservatism in innovative developments.
One of the first modifications of a tank diesel engine in Chelyabinsk was the modernization of the V-2K, designed for heavy tanks. The diesel engine torque was increased, the power was raised to 650 liters. with., while the maximum revolutions of the diesel engine did not touch - the crank mechanism of increased loads could not withstand. This was achieved by reconfiguring the high pressure fuel pump and increasing the fuel supply per cycle. Then there was the V-2IS, which managed to reduce the height by 200 mm and carry out a number of minor improvements. One of the indisputable advantages of the IS tank equipped with such a diesel engine was the 220-kilometer range on one refueling, while the T-VI Tiger could only cover 120 kilometers on the tank. However, such an increase in power did not allow increasing the engine resource - until the end of the 40s, it did not exceed 300 motorcycle hours. Already during the war, it became clear that a further increase in the power of the B-2 with a further increase in the engine resource was possible only with the help of pressurization. One of the first was the V-12 with an AM-38F driven centrifugal supercharger, which allowed the engine to develop 750 hp. with. and provided a torque of 3000 Nm. In November-December 1943, the motor successfully passed 100-hour tests, but after only six months it could no longer repeat them. At the beginning of 1944, the B-2 for heavy tanks, it was decided to change to a new B-11 at once for 700 hp. pp., and in July of the same year the Kirov plant was supposed to produce 75 motors per month. As a result, the first serial motors appeared only at the end of April 1945 and were installed on the IS-3, which did not have time to fight. In 1947, the first serial V-12s for the IS-4 appeared at ChTZ, which were produced in various modifications until the early 60s. Motors of the "heavy" series were installed on the T-10, T-10M and a couple of prototypes.
Sverdlovsk Plant No. 76 (Turbine Plant), also engaged in the production of tank engines, by the fall of 1944 was able to create its own version of a deep modernization of the legendary diesel engine, named B-14. It was a 700-horsepower engine with a cylinder diameter expanded to 160 mm, which increased the working volume to 44.3 liters. Bench tests were also carried out on the supercharged B-14M (the working volume was increased to 44.3 liters), with a capacity of 800 liters. with. A long-awaited novelty appeared on both engines - the cylinder block shirt was now cast at the same time as the heads, which eliminated the notorious problem of the gas joint. This was a direct merit of the designer Timofey Chupakhin, who had been hatching a similar idea since the end of the 30s. Also, a new, more rigid crankcase appeared on the B-14, which became a supporting structure - this increased the reliability of the bearings of the crankshaft and piston group.
Supercharged and non-supercharged
Noteworthy is the development work that took place at the GBTU training ground of the USSR Armed Forces, the purpose of which was to increase the power of the B-2 without pressurization. Then it was once again confirmed that the location of the air cleaners in the engine compartment of the tank directly affects the filling of diesel cylinders with air. It turned out that the T-34 and IS-2 engines pretty much "swallowed" the air heated by their own heat (up to 60 degrees), which, together with clogged filters, reduced the power by 10% at once. The physics of the process is very simple - cold air is denser, therefore, in one working cycle, the motor sucks it in more and the fuel burns more fully in the cylinders. With warm air, the situation is the opposite.
In general, based on the results of work at the GBTU test site, it was concluded that without a critical decrease in the resource of the engine, its power can only be raised to 600 hp. with. Further only with a turbine. In the naturally aspirated version, the base V-2 is accelerated using a whole range of measures - reducing air resistance at the inlet, installing an annular intake manifold for uniform filling of the cylinders of both engine halves (this was spied on from the German tank diesel Mercedes-Benz 507) and the development of a new injection pump. The latter was also planned to be borrowed from Bosch, the pumps of which were mounted on Mercedes-Benz 503A diesel engines. It was also recommended to lower the adjustment tolerance of serial injection pumps in terms of the amount of fuel supply from 6% to 3%. This work was part of a large project for the modernization of the B-2 at the site of the Chelyabinsk Tractor Plant, the management of which did not at all want to make drastic changes in the production cycle.
As you know, it is possible to increase the power of the engine by increasing the working volume (add cylinders or simply increase their dimension), and this, in turn, required serious changes in the design. Therefore, turbocharging has become the main post-war trend in the modernization of the B-2.
The engineers pointed out that the introduction of such a solution would increase the liter capacity by 50-100% at once, while the centrifugal driven supercharger seemed to be the most optimal, giving higher economic indicators. We had to put up with the fact that all this would inevitably cause increased mechanical and thermal loads on the motor.
The next challenge for the engine builders was to increase the engine's warranty operating time to 500-600 hours. Also, to implement the movement of the tank underwater conditions, it was required to ensure the reliability of the operation of the motors with increased resistances at the inlet and outlet.
Several manufacturers of the Soviet Union took part in a kind of competition for the most successful modification of the B-2. In addition to the above-mentioned head SKB # 75 from Chelyabinsk, the plant # 77 "Transmash" in Barnaul was engaged in their program.
Diesel V-16, created by Siberian engineers, developed 600 hp without turbocharging. with. and was distinguished by the absence of a high-pressure fuel pump in the usual sense. It has always been a problematic unit V-2, and in Barnaul it was decided to replace it with individual unit injectors for each cylinder - in many ways a breakthrough solution that became widespread much later. The Barnaul engineers developed the B-16 theme into a whole family - there was a 700-horsepower version for heavy tanks, and an 800-horsepower supercharged B-16NF. They even developed a pair of two diesel engines, from which 1200 hp were removed at the stand. with. But all work on the projects was curtailed either due to the closure of the development of experimental tanks for which they were built, or due to the general cooling of the state towards the tank theme.
In the early 1950s, the leadership had the impression that all military problems could be solved with missiles, while the rest of the armament had a subordinate role. Sobering up came somewhere in 1954, when the NATO countries began, if not to overtake the tank motor-building program of the USSR, then at least to reduce the gap. The Chelyabinsk multi-fuel V-27, equipped with a TKR-11F turbocharger and developing a capacity of 700 hp, has become a real symbol of the revival. with. In the future, the design evolved into the well-known B-46-6 and B-84, which became the real crowns of the B-2 concept.
The next manufacturer, included in the race for the post-war improvement of the B-2, was the aforementioned Ural Turbomotor Plant, which developed a version of the engine under the letter "M". It was a profound rethinking of the diesel concept, most of which were completely new. The V-2M received two TKR-14 turbochargers, which in the future were supposed to be equipped with charge air cooling units - a revolutionary solution at that time. Now such units (intercoolers) can be found in the engines of mainline tractors. In addition to turbocharging, the engine received a new injection pump, improved cooling and lubrication systems, as well as many reinforced units compared to the ancestor. By 1968, the engine was ready, but the difficulties with launching it into production, as well as its large dimensions, did not contribute to its adoption. But many of the solutions of Sverdlovsk designers were used in the next generations of tank diesel engines.
Germans, tanks and diesels
Dieselization of medium and heavy vehicles in the 40s in the Soviet Union was a unique event in world industrial history. No one in the world, except Japan, has used diesel engines on armored vehicles so massively. For comparison: the American "Sherman" of its thirteen modifications had only one M4A2 with a twin diesel power plant. Why, for example, in Germany during the war did not come up with the idea of installing a diesel engine in a tank? There are many versions, starting with a shortage of aluminum and alloy steels and ending with the incompetence of German engineers in the field of creating land heavy diesel engines. Interesting in this regard is the opinion of senior technician-lieutenant S. B. Chistozvonov, which he stated on the pages of the Bulletin of Tank Industry for 1944 (No. 2-3).
In the article "German Tank Engines" the author analyzes in sufficient detail the enemy's engines existing at that time, and at the end analyzes the reasons for the refusal of the Germans from tank diesel engines. Chistozvonov rightly points out that even before the war there were Junkers and Daimler-Benz aircraft diesels in Nazi Germany, which, after a little modification, could well have been installed in armored vehicles. However, German engineers considered it impractical. Why? In fact, among the advantages of a diesel engine, the author notes only a relatively low fuel consumption (20-30% lower than that of a carburetor analogue) and low cost of fuel. Lieutenant Chistozvonov suggests in the article that the Germans did not start dealing with a diesel engine, since a gasoline engine is cheaper, simpler, more compact, more reliable in cold weather, does not require scarce alloy steels and highly skilled assemblers.
At the same time, the life of a tank in the battlefield is so short that it more than negates all the advantages of a diesel engine (read: B-2). The author considers the ideas about the fire safety of engines with compression ignition to be far-fetched - the hit of a projectile in the tank, engine compartment or a simple Molotov cocktail is guaranteed to cause a fire in the MTO of a tank with a diesel engine. In this case, the diesel tank had no advantage over the gasoline tank. The specific fuel balance of Germany also played a role in the choice of the type of power plant for tanks. Synthetic gasolines, benzene and alcohol mixtures prevailed in the German balance sheet, and were unsuitable as fuel for diesel engines. In general, the article for 1944 turned out to be very bold.
At the end of the article there is an interesting remark from the editorial board of the Tank Industry Bulletin:
"The arguments justifying the refusal of the Germans to use diesel engines on their tanks are the assumption of the author himself."
