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106-604: It is a highly upgraded version of Pakistan's ageing Chinese Type 59 tanks (a design that in turn was based on the Soviet T-54A from the mid-1950s), developed with Ukrainian assistance and manufactured by the Heavy Industries Taxila (HIT) – the hub of Pakistani tanks and tracked vehicles, featuring a 125 mm smoothbore gun as primary weapon. The Al-Zarrar can achieve a maximum speed of 65 km (40 mi) per hour, weighs around 44 tons and has

212-414: A carcinogen or "probable carcinogen" and is known to increase the risk of heart and respiratory diseases. In principle, a diesel engine does not require any sort of electrical system. However, most modern diesel engines are equipped with an electrical fuel pump, and an electronic engine control unit. However, there is no high-voltage electrical ignition system present in a diesel engine. This eliminates

318-414: A laser range-finder for accurate range information and ballistics computer to improve accuracy. An improved gun control system is also fitted. The secondary armament consists of an external 12.7 mm anti-aircraft machine gun mounted on the roof of the turret, which can be aimed and fired from inside the tank, and a 7.62 mm coaxial machine gun. The Al-Zarrar is powered by an upgraded version of

424-406: A Pakistani DU (depleted uranium) round, the 125 mm Naiza. Naiza is capable of penetrating 550 mm of RHA armour at a distance of 2 km. The gun has a dual-axis stabilization system and thermal imaging sights integrated into the fire-control system for the commander and gunner, giving it enhanced night-time target acquisition capabilities. The image stabilized fire-control system includes

530-452: A diesel engine drops at lower loads, however, it does not drop quite as fast as the Otto (spark ignition) engine's. Diesel engines are combustion engines and, therefore, emit combustion products in their exhaust gas . Due to incomplete combustion, diesel engine exhaust gases include carbon monoxide , hydrocarbons , particulate matter , and nitrogen oxides pollutants. About 90 per cent of

636-516: A few degrees releasing the pressure and is controlled by a mechanical governor, consisting of weights rotating at engine speed constrained by springs and a lever. The injectors are held open by the fuel pressure. On high-speed engines the plunger pumps are together in one unit. The length of fuel lines from the pump to each injector is normally the same for each cylinder in order to obtain the same pressure delay. Direct injected diesel engines usually use orifice-type fuel injectors. Electronic control of

742-407: A finite area, and the net output of work during a cycle is positive. The fuel efficiency of diesel engines is better than most other types of combustion engines, due to their high compression ratio, high air–fuel equivalence ratio (λ) , and the lack of intake air restrictions (i.e. throttle valves). Theoretically, the highest possible efficiency for a diesel engine is 75%. However, in practice

848-655: A four-man crew: commander, gunner, loader and driver. Although the upgrade program started in 1990 the Al-Zarrar did not enter military service with the Pakistan Army Armoured Corps until 2004, gradually replacing the Type 59s. It is the most plentiful tank in Pakistan's arsenal, with over 500 units in service and an additional 600 Type-59s to be upgraded. Attempts were made to export the Al-Zarrar to

954-452: A fuel consumption of 519 g·kW ·h . However, despite proving the concept, the engine caused problems, and Diesel could not achieve any substantial progress. Therefore, Krupp considered rescinding the contract they had made with Diesel. Diesel was forced to improve the design of his engine and rushed to construct a third prototype engine. Between 8 November and 20 December 1895, the second prototype had successfully covered over 111 hours on

1060-409: A full set of valves, two-stroke diesel engines have simple intake ports, and exhaust ports (or exhaust valves). When the piston approaches bottom dead centre, both the intake and the exhaust ports are "open", which means that there is atmospheric pressure inside the cylinder. Therefore, some sort of pump is required to blow the air into the cylinder and the combustion gasses into the exhaust. This process

1166-562: A heterogeneous air-fuel mixture. The torque a diesel engine produces is controlled by manipulating the air-fuel ratio (λ) ; instead of throttling the intake air, the diesel engine relies on altering the amount of fuel that is injected, and thus the air-fuel ratio is usually high. The diesel engine has the highest thermal efficiency (see engine efficiency ) of any practical internal or external combustion engine due to its very high expansion ratio and inherent lean burn, which enables heat dissipation by excess air. A small efficiency loss

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1272-403: A low-pressure loop at the bottom of the diagram. At 1 it is assumed that the exhaust and induction strokes have been completed, and the cylinder is again filled with air. The piston-cylinder system absorbs energy between 1 and 2 – this is the work needed to compress the air in the cylinder, and is provided by mechanical kinetic energy stored in the flywheel of the engine. Work output is done by

1378-713: A modernized version. North Korea operates Kok'san – 170 mm artillery piece, based on the Type 59 chassis. Royal Ordnance designed variants with 105 mm Royal Ordnance L7 gun as an upgrade package for owners of the Type 59. The upgrades incorporated 105 mm L7A3 gun with thermal sleeve and ammunition stowage of 34 rounds, British smoke grenade dischargers on both sides of the turret, Graviner fire-suppression system, Vickers Instruments L50 gunner's sight with laser-rangefinder, Avimo driver's sight night-vision device, Marconi 's Centaur weapon system with digital FCS, Mantis commander's sight and solid-state drives. Another upgrade package also installed ROMOR-A reactive armour on

1484-532: A more efficient replacement for stationary steam engines . Since the 1910s, they have been used in submarines and ships. Use in locomotives , buses, trucks, heavy equipment , agricultural equipment and electricity generation plants followed later. In the 1930s, they slowly began to be used in some automobiles . Since the 1970s energy crisis , demand for higher fuel efficiency has resulted in most major automakers, at some point, offering diesel-powered models, even in very small cars. According to Konrad Reif (2012),

1590-681: A notable exception being the EMD 567 , 645 , and 710 engines, which are all two-stroke. The power output of medium-speed diesel engines can be as high as 21,870 kW, with the effective efficiency being around 47-48% (1982). Most larger medium-speed engines are started with compressed air direct on pistons, using an air distributor, as opposed to a pneumatic starting motor acting on the flywheel, which tends to be used for smaller engines. Medium-speed engines intended for marine applications are usually used to power ( ro-ro ) ferries, passenger ships or small freight ships. Using medium-speed engines reduces

1696-535: A petroleum engine with glow-tube ignition in the early 1890s; he claimed against his own better judgement that his glow-tube ignition engine worked the same way Diesel's engine did. His claims were unfounded and he lost a patent lawsuit against Diesel. Other engines, such as the Akroyd engine and the Brayton engine , also use an operating cycle that is different from the diesel engine cycle. Friedrich Sass says that

1802-415: A poorer power-to-mass ratio than an equivalent petrol engine. The lower engine speeds (RPM) of typical diesel engines results in a lower power output. Also, the mass of a diesel engine is typically higher, since the higher operating pressure inside the combustion chamber increases the internal forces, which requires stronger (and therefore heavier) parts to withstand these forces. The distinctive noise of

1908-418: A powered system which allowed the gun to be aimed at between +17 and −4 degrees (the average depression for Western tanks is -10, which allows for better usage of hull-down tactics). Later models added vertical stabilization to make firing on the move practical. An infrared searchlight-based night vision system was retrofitted to the tank with an infrared periscope for the commander gunner and driver. The tank

2014-447: A prominent gap between the first and second road wheel. The track is driven by a drive sprocket at the rear, with an idler at the front. It is notable that there are no return rollers. The suspension is a torsion bar system. Engine exhaust is on the left fender. Ammunition is stored inside the turret, which increases the odds of a catastrophic secondary explosion should the tank's interior be penetrated by enemy fire. Crew survivability

2120-408: A regular trunk-piston. Two-stroke engines have a limited rotational frequency and their charge exchange is more difficult, which means that they are usually bigger than four-stroke engines and used to directly power a ship's propeller. Four-stroke engines on ships are usually used to power an electric generator. An electric motor powers the propeller. Both types are usually very undersquare , meaning

2226-533: A renowned project manager, Engineer Mahmood Khan. The first batch of 88 Al-Zarrars were delivered to the Pakistan Army on 26 February 2004 and General Pervez Musharraf attended the delivery ceremony. Al-Zarrar's primary armament is a 125 mm smoothbore tank gun with an autofrettaged , chrome-plated gun barrel. It is a Chinese non-licensed clone of 2A46 capable of firing APFSDS , HEAT -FS and HE -FS rounds as well as anti-tank guided missiles and

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2332-435: A simple mechanical injection system since exact injection timing is not as critical. Most modern automotive engines are DI which have the benefits of greater efficiency and easier starting; however, IDI engines can still be found in the many ATV and small diesel applications. Indirect injected diesel engines use pintle-type fuel injectors. Early diesel engines injected fuel with the assistance of compressed air, which atomised

2438-536: A single orifice injector. The pre-chamber has the disadvantage of lowering efficiency due to increased heat loss to the engine's cooling system, restricting the combustion burn, thus reducing the efficiency by 5–10%. IDI engines are also more difficult to start and usually require the use of glow plugs. IDI engines may be cheaper to build but generally require a higher compression ratio than the DI counterpart. IDI also makes it easier to produce smooth, quieter running engines with

2544-527: A single speed for long periods. Two-stroke engines use a combustion cycle which is completed in two strokes instead of four strokes. Filling the cylinder with air and compressing it takes place in one stroke, and the power and exhaust strokes are combined. The compression in a two-stroke diesel engine is similar to the compression that takes place in a four-stroke diesel engine: As the piston passes through bottom centre and starts upward, compression commences, culminating in fuel injection and ignition. Instead of

2650-426: A small chamber called a swirl chamber, precombustion chamber, pre chamber or ante-chamber, which is connected to the cylinder by a narrow air passage. Generally the goal of the pre chamber is to create increased turbulence for better air / fuel mixing. This system also allows for a smoother, quieter running engine, and because fuel mixing is assisted by turbulence, injector pressures can be lower. Most IDI systems use

2756-530: A source of radio frequency emissions (which can interfere with navigation and communication equipment), which is why only diesel-powered vehicles are allowed in some parts of the American National Radio Quiet Zone . To control the torque output at any given time (i.e. when the driver of a car adjusts the accelerator pedal ), a governor adjusts the amount of fuel injected into the engine. Mechanical governors have been used in

2862-400: A spark plug ( compression ignition rather than spark ignition ). In the diesel engine, only air is initially introduced into the combustion chamber. The air is then compressed with a compression ratio typically between 15:1 and 23:1. This high compression causes the temperature of the air to rise. At about the top of the compression stroke, fuel is injected directly into the compressed air in

2968-417: A swirl chamber or pre-chamber are called indirect injection (IDI) engines. Most direct injection diesel engines have a combustion cup in the top of the piston where the fuel is sprayed. Many different methods of injection can be used. Usually, an engine with helix-controlled mechanic direct injection has either an inline or a distributor injection pump. For each engine cylinder, the corresponding plunger in

3074-422: A two-stroke ship diesel engine has a single-stage turbocharger with a turbine that has an axial inflow and a radial outflow. In general, there are three types of scavenging possible: Crossflow scavenging is incomplete and limits the stroke, yet some manufacturers used it. Reverse flow scavenging is a very simple way of scavenging, and it was popular amongst manufacturers until the early 1980s. Uniflow scavenging

3180-521: Is a Chinese-produced version of the Soviet T-54A tank, an early model of the ubiquitous T-54/55 series. The first vehicles were produced in 1958 and it was accepted into service in 1959, with serial production beginning in 1963. Over 9,500 of the tanks were produced by the time production ended in 1985 with approximately 5,500 serving with the Chinese armed forces. The tank formed the backbone of

3286-461: Is a combustion engine that is more efficient than a diesel engine, but due to its mass and dimensions, is unsuitable for many vehicles, including watercraft and some aircraft . The world's largest diesel engines put in service are 14-cylinder, two-stroke marine diesel engines; they produce a peak power of almost 100 MW each. Diesel engines may be designed with either two-stroke or four-stroke combustion cycles . They were originally used as

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3392-423: Is a simplified and idealised representation of the events involved in a diesel engine cycle, arranged to illustrate the similarity with a Carnot cycle . Starting at 1, the piston is at bottom dead centre and both valves are closed at the start of the compression stroke; the cylinder contains air at atmospheric pressure. Between 1 and 2 the air is compressed adiabatically – that is without heat transfer to or from

3498-431: Is also avoided compared with non-direct-injection gasoline engines, as unburned fuel is not present during valve overlap, and therefore no fuel goes directly from the intake/injection to the exhaust. Low-speed diesel engines (as used in ships and other applications where overall engine weight is relatively unimportant) can reach effective efficiencies of up to 55%. The combined cycle gas turbine (Brayton and Rankine cycle)

3604-403: Is approximately 5 MW. Medium-speed engines are used in large electrical generators, railway diesel locomotives , ship propulsion and mechanical drive applications such as large compressors or pumps. Medium speed diesel engines operate on either diesel fuel or heavy fuel oil by direct injection in the same manner as low-speed engines. Usually, they are four-stroke engines with trunk pistons;

3710-498: Is armed with four QN-502C anti-tank missiles, twenty QN-201 multi-purpose mini missiles, four S-570 loitering munitions, an unmanned 30 mm cannon, a 7.62 mm machine gun, six grenade launchers, and a quadcopter surveillance drone. The Type 59 Durjoy is a highly modernized version of the Bangladesh Army . The Bangladesh Army's old Type 59 tanks were upgraded similar to Type 59G standard at 902 Central Workshop of

3816-429: Is called scavenging . The pressure required is approximately 10-30 kPa. Due to the lack of discrete exhaust and intake strokes, all two-stroke diesel engines use a scavenge blower or some form of compressor to charge the cylinders with air and assist in scavenging. Roots-type superchargers were used for ship engines until the mid-1950s, however since 1955 they have been widely replaced by turbochargers. Usually,

3922-404: Is done on the system to which the engine is connected. During this expansion phase the volume of the gas rises, and its temperature and pressure both fall. At 4 the exhaust valve opens, and the pressure falls abruptly to atmospheric (approximately). This is unresisted expansion and no useful work is done by it. Ideally the adiabatic expansion should continue, extending the line 3–4 to the right until

4028-484: Is fitted to inform the tank crew if the tank is targeted by a laser range-finder or laser designator . Smoke grenade launchers are fitted to the sides of the turret. An automatic fire-extinguishing and explosion suppression system is installed to improve crew survivability. Background: History of the tank , Tank classification Type 59 tank The Type 59 ( Chinese : 59式 ; pinyin : Wǔ jiǔ shì ; industrial designation: WZ-120 ) main battle tank

4134-637: Is hence low. After the signing of the Sino-Soviet Treaty of Friendship , Alliance, and Mutual Assistance, the Soviets agreed to assist China in building a tank manufacturing facility to manufacture the T-54 A MBT in 1956. Initially, the tanks were assembled with Soviet-supplied parts, which were gradually replaced by Chinese-made components. The tank was accepted into service by the PLA in 1959, and given

4240-464: Is more complicated to make but allows the highest fuel efficiency; since the early 1980s, manufacturers such as MAN and Sulzer have switched to this system. It is standard for modern marine two-stroke diesel engines. So-called dual-fuel diesel engines or gas diesel engines burn two different types of fuel simultaneously , for instance, a gaseous fuel and diesel engine fuel. The diesel engine fuel auto-ignites due to compression ignition, and then ignites

4346-463: Is powered by a Model 12150L V-12 liquid-cooled diesel engine , which develops 390 kilowatts (520  hp ) at 2,000 rpm. The engine feeds a manual gearbox with five forward and one reverse gear. A total of 815 litres of diesel can be carried internally in the tank, with a further 400 litres carried externally giving a maximum road range of 600 kilometers, or approximately 430 km using only internal fuel. The tank has five road wheels on each side with

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4452-523: The Bangladesh Army in 2008 to replace its massive fleet of Type 59 tanks through the technology transfer . However, Bangladesh Army later upgraded its Type-59 tanks to Type 59 Durjoy , Pakistan Army remained its sole operator. It was decided by the Pakistan Army that their inventory of Chinese origin Type 59 tanks was too large to be discarded and replaced, so a phased upgrade programme was started by Heavy Industries Taxila (HIT) in 1990. The idea

4558-542: The Bangladesh Machine Tools Factory with Chinese assistance. Bangladesh Army renamed the tank as Durjoy ( Bengali : দুর্জয় ). Improvements includes: France France acquired a Type 59 to modify it to sell a new upgrade package made by Giat industry, to other countries, notably in the development of a new tank for Egypt which seeks a new tank based on the T-62 with western weaponry. the tank

4664-605: The Battle of Longewala and Battle of Chamb , where Pakistani Type 59 tanks faced Indian T-54 and T-55 tanks. Following the Vietnam War, the Sino-Vietnamese War of 1979 was the next largest use of Type 59 tanks to date in modern Chinese military history. China committed nearly 300 Type 59, Type 62 , and Type 63 tanks and armoured fighting vehicles (AFVs) into the conflict against their former ally, with 48 of

4770-507: The EU average for diesel cars at the time accounted for half of newly registered cars. However, air pollution and overall emissions are more difficult to control in diesel engines compared to gasoline engines, and the use of diesel auto engines in the U.S. is now largely relegated to larger on-road and off-road vehicles . Though aviation has traditionally avoided using diesel engines, aircraft diesel engines have become increasingly available in

4876-722: The United Kingdom , and the United States for "Method of and Apparatus for Converting Heat into Work". In 1894 and 1895, he filed patents and addenda in various countries for his engine; the first patents were issued in Spain (No. 16,654), France (No. 243,531) and Belgium (No. 113,139) in December 1894, and in Germany (No. 86,633) in 1895 and the United States (No. 608,845) in 1898. Diesel

4982-416: The 21st century. Since the late 1990s, for various reasons—including the diesel's inherent advantages over gasoline engines, but also for recent issues peculiar to aviation—development and production of diesel engines for aircraft has surged, with over 5,000 such engines delivered worldwide between 2002 and 2018, particularly for light airplanes and unmanned aerial vehicles . In 1878, Rudolf Diesel , who

5088-454: The Carnot cycle. Diesel was also introduced to a fire piston , a traditional fire starter using rapid adiabatic compression principles which Linde had acquired from Southeast Asia . After several years of working on his ideas, Diesel published them in 1893 in the essay Theory and Construction of a Rational Heat Motor . Diesel was heavily criticised for his essay, but only a few found

5194-566: The Chinese People's Liberation Army armoured units until the early 2000s, with an estimated 5,000 of the later Type 59-I and Type 59-II variants in service in 2002. The Type 59 was modified several times during its service. It was also the basis of several later Chinese tank designs including the Type 69 and Type 79 tanks. The Type 59 is almost identical to the early production Soviet T-54As, but there are some key differences. The Type 59

5300-783: The Chinese government's violent crackdown on the 1989 Tiananmen Square protests , a column of which were obstructed in the Tank Man incident. The Type 59s of the Zairian Special Presidential Division saw limited action in 1998 against the rebels of the Alliance of Democratic Forces for the Liberation of Congo . In the late 1950s, the PLA submitted requirements for a light tank more suitable for operations in China's southern region. Development on

5406-490: The PLA to develop new second-generation MBTs. The Type 62 tank received a major upgrade in 2000, with new welded turret, vertically stabilised 105 mm rifled gun, fire-control system, night vision device, smoke grenade launchers, and explosive reactive armor (ERA) package. This vehicle is also known as the ZTQ62. Improved Type 59 MBT built by 617 Factory (Inner Mongolia First Machine Group Co. Ltd). Only saw limited service in

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5512-486: The PLA, but was an export success in the 1980s with more than 2,000 sold worldwide. This armoured recovery vehicle is a Type 59 with its turret removed. The vehicle is armed with a single 12.7 mm machine gun. This armoured recovery vehicle is not believed to have a winch and is limited to towing operations. The modernized HIFV model of Type 59 weighs around 40 tons (or around 35 tons, sources differ here) and can carry up to seven passengers. Modifications include moving

5618-461: The Pakistan Army, who selected the final version of the tank, dubbed Al-Zarrar. By mid 2004, it was expected that 50 AL-Zarrar tanks would be exported to other countries. The Al-Zarrar is a modern MBT developed and manufactured by HIT of Pakistan for the Pakistan Army. An upgraded variant of the Chinese Type 59 tank, the Al-Zarrar is cost-effective modern replacement for the Type 59 fleet of

5724-437: The Pakistan Army. Equipped with modern armament , fire control and ballistic protection, the Al-Zarrar upgrade is also offered by HIT to the armies of foreign countries to upgrade their T-54 / T-55 or Type 59 tanks to Al-Zarrar standard. 54 modifications made to the Type 59 make the Al-Zarrar effectively a new tank. The Al-Zarrar development programme started in 1990. HIT began mass production of Al-Zarrar on 6 May 2003 under

5830-552: The Russian 12.7 mm M1938/46 DShKM heavy machine gun) is provided above the gunner's hatch for which 200 rounds are carried. 3,500 rounds of 7.62 mm ammunition are normally carried. The turret has a powered traverse mechanism that is probably comparable to the T-54 traverse mechanism which can rotate the turret through 360 degrees in 21 seconds. Very early models of the Type 59 gun had manual elevation gear, later replaced with

5936-540: The Type 59. The Marksman consisted of a twin 35 mm autocannon system in a turret that could be fitted to almost any MBT. Background: History of the tank , Tank classification , Tanks in the Cold War Diesel engine The diesel engine , named after the German engineer Rudolf Diesel , is an internal combustion engine in which ignition of the fuel is caused by the elevated temperature of

6042-400: The Type 62 include the Type 79 recovery vehicle (prototype only) and Type 82 earth-mover. The PLA deployed the Type 62 light tank to Vietnam during the 1979 Sino-Vietnam conflict . They found that the thin armour of the Type 62 tank could be penetrated easily by hand-held anti-tank weapons, such as the 40 mm RPG. The Type 62 tank suffered severe losses during the conflict, which convinced

6148-676: The Type-59's original liquid-cooled 12-cylinder diesel engine , boosting the power output from 580 horsepower to 730 hp (540 kW) and torque output of 305 kg.m at 1300–1400 rpm. A combat weight of 40 tonnes gives Al-Zarrar a power-to-weight ratio of 18.3 hp/tonne and a top speed of 65 km/h. Crew comfort is improved over the Type 59 by a modified torsion bar suspension system. Al-Zarrar uses modular composite armour and explosive reactive armour to give improved protection from anti-tank missiles, mines and other weapons. The Pakistani ATCOP LTS-1 laser threat warning system

6254-451: The air in the cylinder due to mechanical compression ; thus, the diesel engine is called a compression-ignition engine (CI engine). This contrasts with engines using spark plug -ignition of the air-fuel mixture, such as a petrol engine ( gasoline engine) or a gas engine (using a gaseous fuel like natural gas or liquefied petroleum gas ). Diesel engines work by compressing only air, or air combined with residual combustion gases from

6360-400: The amount of fuel injected into the engine. Due to the amount of air being constant (for a given RPM) while the amount of fuel varies, very high ("lean") air-fuel ratios are used in situations where minimal torque output is required. This differs from a petrol engine, where a throttle is used to also reduce the amount of intake air as part of regulating the engine's torque output. Controlling

6466-470: The bore is smaller than the stroke. Low-speed diesel engines (as used in ships and other applications where overall engine weight is relatively unimportant) often have an effective efficiency of up to 55%. Like medium-speed engines, low-speed engines are started with compressed air, and they use heavy oil as their primary fuel. Four-stroke engines use the combustion cycle described earlier. Most smaller diesels, for vehicular use, for instance, typically use

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6572-448: The combustion chamber, the droplets continue to vaporise from their surfaces and burn, getting smaller, until all the fuel in the droplets has been burnt. Combustion occurs at a substantially constant pressure during the initial part of the power stroke. The start of vaporisation causes a delay before ignition and the characteristic diesel knocking sound as the vapour reaches ignition temperature and causes an abrupt increase in pressure above

6678-418: The combustion chamber. This may be into a (typically toroidal ) void in the top of the piston or a pre-chamber depending upon the design of the engine. The fuel injector ensures that the fuel is broken down into small droplets, and that the fuel is distributed evenly. The heat of the compressed air vaporises fuel from the surface of the droplets. The vapour is then ignited by the heat from the compressed air in

6784-425: The compressed gas. Combustion and heating occur between 2 and 3. In this interval the pressure remains constant since the piston descends, and the volume increases; the temperature rises as a consequence of the energy of combustion. At 3 fuel injection and combustion are complete, and the cylinder contains gas at a higher temperature than at 2. Between 3 and 4 this hot gas expands, again approximately adiabatically. Work

6890-452: The compression ratio in a spark-ignition engine where fuel and air are mixed before entry to the cylinder is limited by the need to prevent pre-ignition , which would cause engine damage. Since only air is compressed in a diesel engine, and fuel is not introduced into the cylinder until shortly before top dead centre ( TDC ), premature detonation is not a problem and compression ratios are much higher. The pressure–volume diagram (pV) diagram

6996-473: The compression required for his cycle: By June 1893, Diesel had realised his original cycle would not work, and he adopted the constant pressure cycle. Diesel describes the cycle in his 1895 patent application. Notice that there is no longer a mention of compression temperatures exceeding the temperature of combustion. Now it is simply stated that the compression must be sufficient to trigger ignition. In 1892, Diesel received patents in Germany , Switzerland ,

7102-416: The concept of air-blast injection from George B. Brayton , albeit that Diesel substantially improved the system. On 17 February 1894, the redesigned engine ran for 88 revolutions – one minute; with this news, Maschinenfabrik Augsburg's stock rose by 30%, indicative of the tremendous anticipated demands for a more efficient engine. On 26 June 1895, the engine achieved an effective efficiency of 16.6% and had

7208-424: The cost of smaller ships and increases their transport capacity. In addition to that, a single ship can use two smaller engines instead of one big engine, which increases the ship's safety. Low-speed diesel engines are usually very large in size and mostly used to power ships . There are two different types of low-speed engines that are commonly used: Two-stroke engines with a crosshead, and four-stroke engines with

7314-498: The designation Type 59. Over the years, the Type 59 design was enhanced with various domestically developed and western technologies; when the PLA captured a Soviet T-62 during the Sino-Soviet border conflict in 1969, improvements based on the T-62 were incorporated into the Type 59 design to become the Type 69 MBT. The Type 69 was further upgraded with Western technology and became the Type 79 MBT. The Type 59 was, therefore,

7420-616: The diesel engine is Diesel's "very own work" and that any "Diesel myth" is " falsification of history ". Diesel sought out firms and factories that would build his engine. With the help of Moritz Schröter and Max Gutermuth  [ de ] , he succeeded in convincing both Krupp in Essen and the Maschinenfabrik Augsburg . Contracts were signed in April 1893, and in early summer 1893, Diesel's first prototype engine

7526-417: The efficiency is much lower, with efficiencies of up to 43% for passenger car engines, up to 45% for large truck and bus engines, and up to 55% for large two-stroke marine engines. The average efficiency over a motor vehicle driving cycle is lower than the diesel engine's peak efficiency (for example, a 37% average efficiency for an engine with a peak efficiency of 44%). That is because the fuel efficiency of

7632-679: The engine to the front of the vehicle chassis, increasing tank armour including explosive reactive armour on all sides, and installing a rear door for dismounting infantry. the VN11 uses a turret similar to the Type 86 turret. It is a modernised variant of the Type 59 using the tank's chassis similar to its Russian counterpart the BMPT Terminator . The vehicle was first appeared at the Zhuhai Air Show in China in November 2018, and

7738-408: The environment – by the rising piston. (This is only approximately true since there will be some heat exchange with the cylinder walls .) During this compression, the volume is reduced, the pressure and temperature both rise. At or slightly before 2 (TDC) fuel is injected and burns in the compressed hot air. Chemical energy is released and this constitutes an injection of thermal energy (heat) into

7844-406: The exhaust (known as exhaust gas recirculation , "EGR"). Air is inducted into the chamber during the intake stroke, and compressed during the compression stroke. This increases air temperature inside the cylinder so that atomised diesel fuel injected into the combustion chamber ignites. With the fuel being injected into the air just before combustion, the dispersion of fuel is uneven; this is called

7950-464: The first in China's first generation of main battle tanks, the Type 79 being the last. The Type 79 was superseded by the Type 80 second-generation MBT. The Type 59 MBT is also known as WZ-120 by its manufacturer. Over 10,000 were produced between 1959 and the mid-1980s. The Type 59 and its successor, the Type 69, were widely exported, with thousands sold overseas. Today an estimated 5,000 Type 59 MBTs remain in PLA inventory, but it's being supplanted by

8056-463: The four-stroke cycle. This is due to several factors, such as the two-stroke design's narrow powerband which is not particularly suitable for automotive use and the necessity for complicated and expensive built-in lubrication systems and scavenging measures. The cost effectiveness (and proportion of added weight) of these technologies has less of an impact on larger, more expensive engines, while engines intended for shipping or stationary use can be run at

8162-399: The front left of the hull, and is provided with a hatch immediately above his seat, which opens to the left. The driver has two pop-up vision blocks which give coverage ahead and slightly to the right when buttoned up. The commander sits in the turret along with the gunner and loader. The commander's hatch is on the turret left, with the gunner sitting forward and below him. The loader sits on

8268-616: The fuel and forced it into the engine through a nozzle (a similar principle to an aerosol spray). The nozzle opening was closed by a pin valve actuated by the camshaft . Although the engine was also required to drive an air compressor used for air-blast injection, the efficiency was nonetheless better than other combustion engines of the time. However the system was heavy and it was slow to react to changing torque demands, making it unsuitable for road vehicles. A unit injector system, also known as "Pumpe-Düse" ( pump-nozzle in German) combines

8374-700: The fuel injection transformed the direct injection engine by allowing much greater control over the combustion. Common rail (CR) direct injection systems do not have the fuel metering, pressure-raising and delivery functions in a single unit, as in the case of a Bosch distributor-type pump, for example. A high-pressure pump supplies the CR. The requirements of each cylinder injector are supplied from this common high pressure reservoir of fuel. An Electronic Diesel Control (EDC) controls both rail pressure and injections depending on engine operating conditions. The injectors of older CR systems have solenoid -driven plungers for lifting

8480-405: The fuel pump measures out the correct amount of fuel and determines the timing of each injection. These engines use injectors that are very precise spring-loaded valves that open and close at a specific fuel pressure. Separate high-pressure fuel lines connect the fuel pump with each cylinder. Fuel volume for each single combustion is controlled by a slanted groove in the plunger which rotates only

8586-461: The gaseous fuel. Such engines do not require any type of spark ignition and operate similar to regular diesel engines. The fuel is injected at high pressure into either the combustion chamber , "swirl chamber" or "pre-chamber," unlike petrol engines where the fuel is often added in the inlet manifold or carburetor . Engines where the fuel is injected into the main combustion chamber are called direct injection (DI) engines, while those which use

8692-419: The injection needle, whilst newer CR injectors use plungers driven by piezoelectric actuators that have less moving mass and therefore allow even more injections in a very short period of time. Early common rail system were controlled by mechanical means. The injection pressure of modern CR systems ranges from 140 MPa to 270 MPa. An indirect diesel injection system (IDI) engine delivers fuel into

8798-553: The injector and fuel pump into a single component, which is positioned above each cylinder. This eliminates the high-pressure fuel lines and achieves a more consistent injection. Under full load, the injection pressure can reach up to 220 MPa. Unit injectors are operated by a cam and the quantity of fuel injected is controlled either mechanically (by a rack or lever) or electronically. Due to increased performance requirements, unit injectors have been largely replaced by common rail injection systems. The average diesel engine has

8904-476: The mistake that he made; his rational heat motor was supposed to utilise a constant temperature cycle (with isothermal compression) that would require a much higher level of compression than that needed for compression ignition. Diesel's idea was to compress the air so tightly that the temperature of the air would exceed that of combustion. However, such an engine could never perform any usable work. In his 1892 US patent (granted in 1895) #542846, Diesel describes

9010-635: The more capable Type 96 and Type 99 MBTs. The first war involving the Type 59 was in Vietnam, where North Vietnam fielded at least several hundreds supplied directly from their Chinese ally against American tanks used by their South Vietnamese enemy, such as the M41 Walker Bulldog light tank and the M48 Patton main battle tank. Against the US tanks it faced in Vietnam, the Type 59, along with

9116-472: The new Type 62 tank began in 1958, which was a scaled-down Type 59 MBT with simplified equipment. The Type 62 light tank entered batch production in 1963, and approx. 800 were produced by 1978. The Type 62 light tank weights only 21 tons, and is equipped with a Type 62-85TC 85 mm rifled gun, and 3 machine guns. An improved Type 62-I version was produced with better FCS with laser rangefinder, and turret storage racks for added protection. Other versions based on

9222-534: The past, however electronic governors are more common on modern engines. Mechanical governors are usually driven by the engine's accessory belt or a gear-drive system and use a combination of springs and weights to control fuel delivery relative to both load and speed. Electronically governed engines use an electronic control unit (ECU) or electronic control module (ECM) to control the fuel delivery. The ECM/ECU uses various sensors (such as engine speed signal, intake manifold pressure and fuel temperature) to determine

9328-480: The piston (not shown on the P-V indicator diagram). When combustion is complete the combustion gases expand as the piston descends further; the high pressure in the cylinder drives the piston downward, supplying power to the crankshaft. As well as the high level of compression allowing combustion to take place without a separate ignition system, a high compression ratio greatly increases the engine's efficiency. Increasing

9434-403: The piston-cylinder combination between 2 and 4. The difference between these two increments of work is the indicated work output per cycle, and is represented by the area enclosed by the pV loop. The adiabatic expansion is in a higher pressure range than that of the compression because the gas in the cylinder is hotter during expansion than during compression. It is for this reason that the loop has

9540-417: The pollutants can be removed from the exhaust gas using exhaust gas treatment technology. Road vehicle diesel engines have no sulfur dioxide emissions, because motor vehicle diesel fuel has been sulfur-free since 2003. Helmut Tschöke argues that particulate matter emitted from motor vehicles has negative impacts on human health. The particulate matter in diesel exhaust emissions is sometimes classified as

9646-408: The pressure falls to that of the surrounding air, but the loss of efficiency caused by this unresisted expansion is justified by the practical difficulties involved in recovering it (the engine would have to be much larger). After the opening of the exhaust valve, the exhaust stroke follows, but this (and the following induction stroke) are not shown on the diagram. If shown, they would be represented by

9752-719: The regular Artesh and the Islamic Revolutionary Guard Corps . The T-72 proved highly superior to the Chinese tank. On the other hand, Iraq received 1,000 Type 59s from China. The Iraqi Type 59 tanks were later used during the 1991 Gulf War . The Sudan also used Type 59 tanks during the Second Sudanese Civil War . Five were lost to the Sudan People's Liberation Army near Yei in March 1997. Type 59 tanks were involved in

9858-415: The right of the turret and has a hatch above him. The turret has a non-rotating floor, which complicated the crew's operations as they would not rotate with the turret. The turret mounts a rifled 100 mm Type 59 cannon, for which 34 rounds are typically carried. A Type 59T 7.62 mm machine gun is mounted coaxially with the main gun. A Type 54 12.7 mm anti-aircraft machine gun (the Chinese copy of

9964-488: The side hulls and ROMOR-B passive appliqué armour on the front hull and turret, along with the aforementioned upgrades. The Type 59 tanks used in the project were acquired from Pakistan, and the upgraded tanks were exhibited in British Army Equipment Exhibition 1984. No Type 59s served with British forces. Marconi offered their Marksman anti-aircraft system as a conversion to operators of

10070-542: The similar T-54 tank of Soviet origin (also widely operated in the war by North Vietnam), achieved some success against enemy armour. Most of the losses of armour suffered by the US and South Vietnamese forces were to North Vietnamese infantry-based anti-tank weapons, such as the RPG-7, rather than to North Vietnam's own tanks and other armour. The Type 59 was also fielded during the Indo-Pakistani War of 1971 , in

10176-544: The test bench. In the January 1896 report, this was considered a success. In February 1896, Diesel considered supercharging the third prototype. Imanuel Lauster , who was ordered to draw the third prototype " Motor 250/400 ", had finished the drawings by 30 April 1896. During summer that year the engine was built, it was completed on 6 October 1896. Tests were conducted until early 1897. First public tests began on 1 February 1897. Moritz Schröter 's test on 17 February 1897

10282-890: The timing of the start of injection of fuel into the cylinder is similar to controlling the ignition timing in a petrol engine. It is therefore a key factor in controlling the power output, fuel consumption and exhaust emissions. There are several different ways of categorising diesel engines, as outlined in the following sections. Günter Mau categorises diesel engines by their rotational speeds into three groups: High-speed engines are used to power trucks (lorries), buses , tractors , cars , yachts , compressors , pumps and small electrical generators . As of 2018, most high-speed engines have direct injection . Many modern engines, particularly in on-highway applications, have common rail direct injection . On bigger ships, high-speed diesel engines are often used for powering electric generators. The highest power output of high-speed diesel engines

10388-410: The total listed above lost to Vietnamese anti-tank action. The tanks of 42nd Corps, as the vanguard force responsible for cutting off the northern Vietnamese city of Cao Bằng , bore the brunt of the losses in armour and managed to advance only 30 km within 3 days. The poor performance of tanks and AFVs in this battle was attributed to the mountainous and hilly terrain in much of northern Vietnam that

10494-532: Was a student at the "Polytechnikum" in Munich , attended the lectures of Carl von Linde . Linde explained that steam engines are capable of converting just 6–10% of the heat energy into work, but that the Carnot cycle allows conversion of much more of the heat energy into work by means of isothermal change in condition. According to Diesel, this ignited the idea of creating a highly efficient engine that could work on

10600-488: Was attacked and criticised over several years. Critics claimed that Diesel never invented a new motor and that the invention of the diesel engine is fraud. Otto Köhler and Emil Capitaine  [ de ] were two of the most prominent critics of Diesel's time. Köhler had published an essay in 1887, in which he describes an engine similar to the engine Diesel describes in his 1893 essay. Köhler figured that such an engine could not perform any work. Emil Capitaine had built

10706-477: Was built in Augsburg . On 10 August 1893, the first ignition took place, the fuel used was petrol. In winter 1893/1894, Diesel redesigned the existing engine, and by 18 January 1894, his mechanics had converted it into the second prototype. During January that year, an air-blast injection system was added to the engine's cylinder head and tested. Friedrich Sass argues that, it can be presumed that Diesel copied

10812-745: Was called T59 and included a French 105mm gun, a new ballistic computer, new fire-control, French thermal, new sight, and a new fire-extinguisher system. The vehicle was presented in Satory 1987 but saw no success. Pakistan operates Al-Zarrar – Heavy Industries Taxila of Pakistan has introduced the Al-Zarrar Main Battle Tank. The Al-Zarrar series was designed to improve and rebuild the Pakistani army's Type 59 tanks by way of more modern armament, fire control, defensive equipment, etc. Improvements include: Iran operates Type T-72Z -

10918-537: Was inherently unsuitable for mechanized warfare, just like in Korea . The light armour on the Type 62 tank (a lighter version of the Type 59 which predominantly served as a combat-reconnaissance vehicle) also proved inadequate in protection against small and light anti-tank weapons, such as anti-tank grenades . Iran received 300 Type 59 tanks from North Korea and China during the Iran–Iraq War . They were fielded by both

11024-443: Was not originally fitted with the infrared searchlight or main gun stabilization of the T-54. The Type 59 has a conventional post-war layout with an engine compartment at the rear and a cast dome-shaped gun turret in the centre of the hull. The hull is welded steel varying in thickness between 99 mm on the front lower glacis to 20 mm on the hull floor. The turret varies in thickness from 39–100 mm. The driver sits in

11130-424: Was the main test of Diesel's engine. The engine was rated 13.1 kW with a specific fuel consumption of 324 g·kW ·h , resulting in an effective efficiency of 26.2%. By 1898, Diesel had become a millionaire. The characteristics of a diesel engine are The diesel internal combustion engine differs from the gasoline powered Otto cycle by using highly compressed hot air to ignite the fuel rather than using

11236-628: Was to upgrade the firepower, mobility and protection of the Type 59 to allow it to compete on the modern battlefield at a fraction of the cost of a modern main battle tank (MBT) . The first phase of the upgrade programme was completed in 1997. The second phase started in 1998 when HIT began development and testing of a new tank, a Type 59 re-built with over 50 modifications, resulting in three prototypes with slightly differing specifications (different fire-control systems, for example). Many systems originally developed for HIT's Al-Khalid MBT were incorporated. The prototypes underwent extensive testing by HIT and

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