A ceramic engine is an internal combustion engine made from specially engineered ceramic materials. Ceramic engines allow for the compression and expansion of gases at extremely high temperatures without loss of heat or engine damage.[1] Proof-of-concept ceramic engines were popularized by successful studies in the early 1980s and 1990s. Under controlled laboratory conditions, ceramic engines outperformed traditional metal engines in terms of weight, efficiency, and performance. All-ceramic engines were seen as the next advancement in future engine technology, but have not yet entered the automobile market because of manufacturing and economic problems.[2]
Research into more efficient diesel engines occurred after the 1970s energy crisis, resulting in a new market for fuel-efficient vehicles. A newly developed gas turbine engine design promised high thermal efficiency, but needed a material that could withstand 2,500°F (1,370°C) temperatures. The high heat did not allow for readily available materials like metals, superalloys, and carbon composites to be used. As a result, government-funded research facilities in the United States, Japan, Germany, and the United Kingdom experimented with substituting metal for ceramics. Ceramics' high resistance to heat helped pave the way towards the first commercial use of gas turbine engines, the successes of which led to the idea of an all-ceramic engine.[1][3]
Between 1985 and 1989, Nissan, in collaboration with NGK, produced the world's first ceramic turbocharger, later debuting this on the 1985 Fairlady Z 200ZR.[1][4]Isuzu developed a diesel ceramic engine that used ceramic for the pistons, piston rings, and turbocharger wheels.[5] Isuzu also developed an engine that used cylinder liners made of ceramic materials such as silicon nitride. Isuzu also used ceramics for the intake and exhaust valves, exhaust manifold, turbocharger housing, camshafts, heat insulation, and rocker arms.[6][7][8]
Predictions for an adiabatic turbo-compound engine (a theoretical heat-efficient engine) were seen as plausible with the use of technical ceramic material. A 1987 technical paper by Roy Kamo predicted the mass production of such engines to occur in the year 2000. However, these predictions were made with the belief that ceramics would overcome "the design methodology, manufacturing process, machining cost, and mass production quality control needed for high volume production."[9]
Currently, ceramic engines are not viable for mass production. Large parts, like the engine block, can be challenging to manufacture out of ceramics due to their brittleness and stiffness.[citation needed]
Applications
In 1982, Isuzu tested a car with an all-ceramic engine near the Kinko Bay.[10]
A ceramic is any of the various hard, brittle, heat-resistant, and corrosion-resistant materials made by shaping and then firing an inorganic, nonmetallic material, such as clay, at a high temperature. Common examples are earthenware, porcelain, and brick.
The compression ratio is the ratio between the volume of the cylinder and combustion chamber in an internal combustion engine at their maximum and minimum values.
The diesel engine, named after Rudolf Diesel, is an internal combustion engine in which ignition of the fuel is caused by the elevated temperature of the air in the cylinder due to mechanical compression; thus, the diesel engine is called a compression-ignition engine. This contrasts with engines using spark plug-ignition of the air-fuel mixture, such as a petrol engine or a gas engine.
In an internal combustion engine, a turbocharger is a forced induction device that is powered by the flow of exhaust gases. It uses this energy to compress the intake air, forcing more air into the engine in order to produce more power for a given displacement.
A gas turbine or gas turbine engine, by its old name internal combustion turbine, is a type of continuous flow internal combustion engine. The main parts common to all gas turbine engines form the power-producing part and are, in the direction of flow:
A four-strokeengine is an internal combustion (IC) engine in which the piston completes four separate strokes while turning the crankshaft. A stroke refers to the full travel of the piston along the cylinder, in either direction. The four separate strokes are termed:
Intake: Also known as induction or suction. This stroke of the piston begins at top dead center (T.D.C.) and ends at bottom dead center (B.D.C.). In this stroke the intake valve must be in the open position while the piston pulls an air-fuel mixture into the cylinder by producing a partial vacuum in the cylinder through its downward motion.
Compression: This stroke begins at B.D.C, or just at the end of the suction stroke, and ends at T.D.C. In this stroke the piston compresses the air-fuel mixture in preparation for ignition during the power stroke (below). Both the intake and exhaust valves are closed during this stage.
Combustion: Also known as power or ignition. This is the start of the second revolution of the four stroke cycle. At this point the crankshaft has completed a full 360 degree revolution. While the piston is at T.D.C. the compressed air-fuel mixture is ignited by a spark plug or by heat generated by high compression, forcefully returning the piston to B.D.C. This stroke produces mechanical work from the engine to turn the crankshaft.
Exhaust: Also known as outlet. During the exhaust stroke, the piston, once again, returns from B.D.C. to T.D.C. while the exhaust valve is open. This action expels the spent air-fuel mixture through the exhaust port.
A centrifugal supercharger is a specialized type of supercharger that makes use of centrifugal force in order to increase the manifold air pressure, MAP. An increased MAP allows the engine to burn more fuel, which results in an increased power output. Centrifugal superchargers are generally attached to the front of the engine via a belt-drive or gear-drive from the engine's crankshaft.
Internal combustion engine cooling uses either air or liquid to remove the waste heat from an internal combustion engine. For small or special purpose engines, cooling using air from the atmosphere makes for a lightweight and relatively simple system. Watercraft can use water directly from the surrounding environment to cool their engines. For water-cooled engines on aircraft and surface vehicles, waste heat is transferred from a closed loop of water pumped through the engine to the surrounding atmosphere by a radiator.
A microturbine (MT) is a small gas turbine with similar cycles and components to a heavy gas turbine. The MT power-to-weight ratio is better than a heavy gas turbine because the reduction of turbine diameters causes an increase in shaft rotational speed. Heavy gas turbine generators are too large and too expensive for distributed power applications, so MTs are developed for small-scale power like electrical power generation alone or as combined cooling, heating, and power (CCHP) systems. The MT are 25 to 500 kW (34 to 671 hp) gas turbines evolved from piston engine turbochargers, aircraft auxiliary power units (APU) or small jet engines, the size of a refrigerator. Early turbines of 30–70 kW (40–94 hp) grew to 200–250 kW (270–340 hp).
Variable-geometry turbochargers (VGTs), occasionally known as variable-nozzle turbochargers (VNTs), are a type of turbochargers, usually designed to allow the effective aspect ratio of the turbocharger to be altered as conditions change. This is done with the use of adjustable vanes located inside the turbine housing between the inlet and turbine, these vanes affect flow of gases towards the turbine. The benefit of the VGT is that the optimum aspect ratio at low engine speeds is very different from that at high engine speeds.
Twin-turbo refers to an engine in which two turbochargers work in tandem to compress the intake fuel/air mixture. The most common layout features two identical or mirrored turbochargers in parallel, each processing half of a V engine's produced exhaust through independent piping. The two turbochargers can either be matching or different sizes.
Engine efficiency of thermal engines is the relationship between the total energy contained in the fuel, and the amount of energy used to perform useful work. There are two classifications of thermal engines-
Internal combustion and
External combustion engines.
A turbo-compound engine is a reciprocating engine that employs a turbine to recover energy from the exhaust gases. Instead of using that energy to drive a turbocharger as found in many high-power aircraft engines, the energy is instead sent to the output shaft to increase the total power delivered by the engine. The turbine is usually mechanically connected to the crankshaft, as on the Wright R-3350 Duplex-Cyclone, but electric and hydraulic power recovery systems have been investigated as well.
A free-piston engine is a linear, 'crankless' internal combustion engine, in which the piston motion is not controlled by a crankshaft but determined by the interaction of forces from the combustion chamber gases, a rebound device and a load device.
Internal combustion engines date back to between the 10th and 13th centuries, when the first rocket engines were invented in China. Following the first commercial steam engine in 1698, various efforts were made during the 18th century to develop equivalent internal combustion engines. In 1791, the English inventor John Barber patented a gas turbine. In 1794, Thomas Mead patented a gas engine. Also in 1794, Robert Street patented an internal-combustion engine, which was also the first to use liquid fuel (petroleum) and built an engine around that time. In 1798, John Stevens designed the first American internal combustion engine. In 1807, French engineers Nicéphore and Claude Niépce ran a prototype internal combustion engine, using controlled dust explosions, the Pyréolophore. This engine powered a boat on the river in France. The same year, the Swiss engineer François Isaac de Rivaz built and patented a hydrogen and oxygen-powered internal-combustion engine. Fitted to a crude four-wheeled wagon, François Isaac de Rivaz first drove it 100 metres in 1813, thus making history as the first car-like vehicle known to have been powered by an internal-combustion engine.
In materials science ceramic matrix composites (CMCs) are a subgroup of composite materials and a subgroup of ceramics. They consist of ceramic fibers embedded in a ceramic matrix. The fibers and the matrix both can consist of any ceramic material, including carbon and carbon fibers.
MAN Energy Solutions SE is a German multinational company based in Augsburg that produces large-bore gas and diesel engines and also turbomachinery for marine, rail and stationary applications, as locomotive and marine propulsion systems, power plant applications, and turbochargers. The company was formed in 2010 from the merger of MAN Diesel and MAN Turbo. MAN Energy Solutions is a subsidiary of the German carmaker Volkswagen Group.
CuproBraze is a copper-alloy heat exchanger technology for high-temperature and pressure environments such as those in modern diesel engines. The technology, developed by the International Copper Association (ICA), is licensed for free to heat exchanger manufacturers around the world.
An internal combustion engine is a heat engine in which the combustion of a fuel occurs with an oxidizer in a combustion chamber that is an integral part of the working fluid flow circuit. In an internal combustion engine, the expansion of the high-temperature and high-pressure gases produced by combustion applies direct force to some component of the engine. The force is typically applied to pistons, turbine blades, a rotor, or a nozzle. This force moves the component over a distance, transforming chemical energy into kinetic energy which is used to propel, move or power whatever the engine is attached to.
The GMWhirlfire gas turbine engines were developed in the 1950s by the research division of General Motors Corporation and fitted to concept vehicles, including the Firebird concept cars, Turbo-Cruiser buses, and Turbo-Titan trucks through the 1960s. They are free-turbine turboshaft machines with two spools: one compressor/gasifier turboshaft and one power/output turboshaft sharing a common axis without a mechanical coupling between them. Fuel consumption of the first-generation GT-300 was high compared to piston engines, so thermal wheel regenerators were added to the second-generation GT-304, cutting consumption by approximately 1⁄2.
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