Dugald Clerk

Last updated
Sir Dugald Clerk
Dugald Clerk.jpg
Born(1854-03-31)31 March 1854
Glasgow, Scotland, UK
Died12 November 1932(1932-11-12) (aged 78)
Ewhurst, England, UK
NationalityScottish
CitizenshipBritish
OccupationEngineer
Known forDesigned the world's first successful two-stroke engine

Sir Dugald Clerk (sometimes written as Dugald Clark) KBE, LLD FRS [1] (1854, Glasgow – 1932, Ewhurst, Surrey) was a Scottish engineer who designed the world's first successful two-stroke engine [2] [3] in 1878 [4] and patented it in England in 1881. He was a graduate of Anderson's University in Glasgow (now the University of Strathclyde), and Yorkshire College, Leeds (now the University of Leeds). He formed the intellectual property firm with George Croydon Marks, called Marks & Clerk. He was knighted on 24 August 1917. [5]

Contents

Life

Dugald Clerk was born in Glasgow on 31 March 1854, the son of Donald Clerk a machinist and his wife, Martha Symington. He was privately tutored then apprenticed to the firm of Messrs H O Robinson & Co in Glasgow. From 1871 to 1876 he went to Anderson College in Glasgow studying engineering then to the Yorkshire College of Science in Leeds. In the First World War he was Director of Engineering Research for the Admiralty. [6]

He married Margaret Hanney in 1883.

He died in Ewhurst, Surrey on 12 November 1932.

Clerk's work on the internal combustion engine

Sir Dugald Clerk's two-cycle engine Two-stroke vee-twin engine with pumping cylinders (section).jpg
Sir Dugald Clerk's two-cycle engine

Clerk began work on his own engine designs in October 1878 after modifying a Brayton engine with a spark plug. Brayton engines (called "Ready Motors" were made from 1872 - 1876) and were one of the first engines to successfully use compression and combust fuel in the cylinder. Prior to this time the commercial engines available had been the Lenoir engine from 1860, a non - compression engine which worked on a double-acting two-stroke cycle, but spent half of each stroke drawing gas into the cylinder. The Hugon engine was a slightly improved version, but both were quite inefficient (95 and 85 cubic feet of gas per HP hour respectively). The next commercial engine available (from 1867) was the Otto & Langen a non compression, free piston engine, which used atmospheric pressure for the power stroke, and consumed about half the gas of the Lenoir and Hugon engines. It was in May 1876 that Otto developed his engine using the single-acting four-stroke cycle with compression in the cylinder. Clerk decided to develop an engine using compression, but with the two-stroke cycle, as he could see benefit to weight and smoothness of operation through having twice as many power strokes.

"Clerk's initial experiment with a Brayton ready motor in 1878 led him to make improvements that would eventually result in the development of the two-stroke cycle. Clerks engine used compression and a novel system of ignition", one of these was exhibited in July 1879. However it was not until the end of 1880 that he succeeded in producing the Clerk engine operating on the two-stroke cycle, which became the commercial product. Clerk states "The Clerk engine at present in the market was the first to succeed in introducing compression of this type, combined with ignition at every revolution ; many attempts had previously been made by other inventors, including Mr. Otto and the Messrs. Crossley, but all had failed in producing a marketable engine. It is only recently that the Messrs. Crossley have made the Otto engine in its twin form and so succeeded in getting impulse at every turn."

Dugald Clerk was the author of 3 comprehensive books covering the development of the oil and gas engine from its early inception, and including details of his own work in this area. The first edition was produced in 1886, and the notes here are taken from the 7th edition, [7] revised and updated up to 1896. In "Gas and Oil Engines", [7] Clerk refers to the significant earlier gas engine patents of Barnett in 1838 and Wright in 1833.

Clerk cycle

In 1878 Clerk obtained a Brayton "Ready Motor" engine made from 1872-1876 by George Brayton in Philadelphia PA USA. Clerk wondered if he could improve the performance of the engine. He soon outfitted the engine with a spark plug and an improved fuel system. Initially Clerk used one cylinder for compression and the other for expansion. At one point an explosion occurred which broke the engine in two pieces. The engine was repaired and displayed in 1879. Later Clerk decided to abandon use of the pumping cylinder for compression and use it only to transfer the air / fuel mixture into the power cylinder.

Clerk describes his experiments with the Brayton engine 1878 Clerk on Brayton engine.jpg
Clerk describes his experiments with the Brayton engine 1878

The Otto cycle was patented in 1876, immediately recognised to have a significant practical value. [4] Clerk quickly followed with his concept of a two-stroke engine of 1880, that would not infringe the Otto's patent (being a four-stroke engine). [4]

Clerk describes a Cambell engine as using his cycle, as follows: [7] "It has two cylinders, respectively pump and motor, driven from cranks placed at almost right angles to each other, the pump crank leading. The pump takes in a charge of gas and air, and the motor piston overruns a port in the side of the cylinder at the out-end of its stroke to discharge the exhaust gases. When the pressure in the motor cylinder has fallen to atmosphere, the pump forces its charge into the back cover of the motor cylinder through a check valve, displacing before it the products of combustion through an exhaust port ; the motor piston then returns, compressing the contents of the cylinder into the compression space. The charge is then fired and the piston performs its working stroke. This is the Clerk cycle."

The Clerk engine uses automatic 'poppet' type valves for inlet air and gas (one with spring assistance, one without), and a port in the cylinder uncovered by the piston for the exhaust valve. References to a Clerk engine with slide valve may refer to the earlier experiments with a Lenoir type engine. The ignition is by carrying an external flame, using a modification of a method he developed in 1878.

Most engine designs that pre-dated the Otto engine (and Clerk engine), such as those of de Rivaz, the Niépce brothers, Jean Joseph Etienne Lenoir, Samuel Morey, and others, did use two-stroke engines, which were "natural" in the times of steam engine. Clerk's significant contribution was introducing Otto-styled compression to the two-stroke engine, bringing its efficiency up-to-date (for the 1880s). Several manufacturers adopted the Clerk cycle in the short term, though commercial aspects such as patents on the four-stroke cycle were part of this. Many years later the two-stroke engine for large capacity diesels using a turbocharger or supercharger has become common, for example in ships and railway locomotives. With open crankshafts, and the advantages of higher power to weight ratio, these engines are closely aligned with Dugald Clerk's concepts, and the Clerk Cycle.

Pumping cylinder vs supercharger

Clerk's engine was made of two cylinders – one working cylinder and an additional cylinder to charge the cylinder, expelling the exhaust through a port uncovered by the piston. Some sources consider this additional cylinder the world's first [8] supercharger. Clerk himself states that "It is not a compressing pump, and is not intended to compress before introduction into the motor, but merely to exercise force enough to pass the gases through the lift valve into the motor cylinder, and there displace the burnt gases, discharging them into the exhaust pipe." Hence sources recognise it instead as a "pumping cylinder", pointing out that it did not actually compress the fuel-air mixture, it simply moved the fresh mixture to the working cylinder to force out the gasses burnt previously. [3] [4]

Clerk's engine vs modern two-stroke engine

Clerk's original design did not allow the construction of smaller engines, as it required the aforementioned additional pumping cylinder for each working cylinder. [2] [3] The crucial simplification of the concept, that made possible small yet powerful two-stroke engines for mass markets, was patented by Joseph Day [3] in 1894. [2]

Arms

Coat of arms of Dugald Clerk
Sir Dugald Clerk Escutcheon.png
Motto
Fortiter Ubique [10]

See also

Bibliography

Related Research Articles

Miller cycle

In engineering, the Miller cycle is a thermodynamic cycle used in a type of internal combustion engine. The Miller cycle was patented by Ralph Miller, an American engineer, US patent 2817322 dated Dec 24, 1957. The engine may be two- or four-stroke and may be run on diesel fuel, gases, or dual fuel.

Two-stroke engine Internal combustion engine type

A two-strokeengine is a type of internal combustion engine that completes a power cycle with two strokes of the piston during one power cycle, this power cycle being completed in one revolution of the crankshaft. A four-stroke engine requires four strokes of the piston to complete a power cycle during two crankshaft revolutions. In a two-stroke engine, the end of the combustion stroke and the beginning of the compression stroke happen simultaneously, with the intake and exhaust functions occurring at the same time.

Petrol engine Internal combustion engine designed to run on gasoline

A petrol engine or gasoline engine is an internal combustion engine with spark-ignition, designed to run on petrol (gasoline) and similar volatile fuels.

Four-stroke engine Internal combustion engine type

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:

  1. 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 vacuum pressure into the cylinder through its downward motion. The piston is moving down as air is being sucked in by the downward motion against the piston.
  2. 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.
  3. 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.
  4. 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 valve.
Nicolaus Otto German inventor

Nicolaus August Otto was a German engineer who successfully developed the compressed charge internal combustion engine which ran on petroleum gas and led to the modern internal combustion engine. The Association of German Engineers (VDI) created DIN standard 1940 which says "Otto Engine: internal combustion engine in which the ignition of the compressed fuel-air mixture is initiated by a timed spark", which has been applied to all engines of this type since.

Brayton cycle Thermodynamic cycle

The Brayton cycle is a thermodynamic cycle that describes the operation of certain heat engines that have air or some other gas as their working fluid. The original Brayton engines used a piston compressor and piston expander, but modern gas turbine engines and airbreathing jet engines also follow the Brayton cycle. Although the cycle is usually run as an open system, it is conventionally assumed for the purposes of thermodynamic analysis that the exhaust gases are reused in the intake, enabling analysis as a closed system.

Atkinson cycle Thermodynamic cycle

The Atkinson-cycle engine is a type of internal combustion engine invented by James Atkinson in 1882. The Atkinson cycle is designed to provide efficiency at the expense of power density.

Ericsson cycle

The Ericsson cycle is named after inventor John Ericsson who designed and built many unique heat engines based on various thermodynamic cycles. He is credited with inventing two unique heat engine cycles and developing practical engines based on these cycles. His first cycle is now known as the closed Brayton cycle, while his second cycle is what is now called the Ericsson cycle. Ericsson is one of the few who built open-cycle engines, but he also built closed-cycle ones.

William Hall Barnett, is described as a 'founder' in his 1836 patent, and an 'ironfounder' in his 1838 patent, and later as an engineer and gas engineer, working in Brighton, UK. He worked for many years for the Brighton and Hove General Gas Company.

Otto engine Large stationary single-cylinder internal combustion four-stroke engine

The Otto engine was a large stationary single-cylinder internal combustion four-stroke engine designed by the German Nicolaus Otto. It was a low-RPM machine, and only fired every other stroke due to the Otto cycle, also designed by Otto.

George Brayton American mechanical engineer and inventor

George Bailey Brayton was an American mechanical engineer and inventor. He was noted for introducing the constant pressure engine that is the basis for the gas turbine, and which is now referred to as the Brayton cycle.

Timeline of heat engine technology

This Timeline of heat engine technology describes how heat engines have been known since antiquity but have been made into increasingly useful devices since the 17th century as a better understanding of the processes involved was gained. They continue to be developed today.

Hot-bulb engine Internal combustion engine

The hot-bulb engine is a type of internal combustion engine in which fuel ignites by coming in contact with a red-hot metal surface inside a bulb, followed by the introduction of air (oxygen) compressed into the hot-bulb chamber by the rising piston. There is some ignition when the fuel is introduced, but it quickly uses up the available oxygen in the bulb. Vigorous ignition takes place only when sufficient oxygen is supplied to the hot-bulb chamber on the compression stroke of the engine.

The term six-stroke engine has been applied to a number of alternative internal combustion engine designs that attempt to improve on traditional two-stroke and four-stroke engines. Claimed advantages may include increased fuel efficiency, reduced mechanical complexity and/or reduced emissions. These engines can be divided into two groups based on the number of pistons that contribute to the six strokes.

Scavenging (engine) Process of replacing the exhaust gas in a cylinder of an internal combustion engine with the fresh air/fuel mixture

Scavenging is the process of replacing the exhaust gas in a cylinder of an internal combustion engine with the fresh air/fuel mixture for the next cycle. If scavenging is incomplete, the remaining exhaust gases can cause improper combustion for the next cycle, leading to reduced power output.

Hornsby-Akroyd oil engine

The Hornsby-Akroyd oil engine, named after its inventor Herbert Akroyd Stuart and the manufacturer Richard Hornsby & Sons, was the first successful design of an internal combustion engine using heavy oil as a fuel. It was the first to use a separate vapourising combustion chamber and is the forerunner of all hot-bulb engines, which are considered predecessors of the similar Diesel engine, developed a few years later.

Two-stroke diesel engine Engine type

A two-stroke diesel engine is an internal combustion engine that uses compression ignition, with a two-stroke combustion cycle. It was invented by Hugo Güldner in 1899.

History of the internal combustion engine Aspect of history

Various scientists and engineers contributed to the development of 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 the 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 Saône river, France. The same year, the Swiss engineer François Isaac de Rivaz built and patented a hydrogen and oxygen powered internal-combustion engine. The fuel was stored in a balloon and the spark was electrically ignited by a hand-operated trigger. Fitted to a crude four-wheeled wagon, François Isaac de Rivaz first drove it 100 meters in 1813, thus making history as the first car-like vehicle known to have been powered by an internal-combustion engine. In 1823, Samuel Brown patented the first internal combustion engine to be applied industrially in the U.S.; one of his engines pumped water on the Croydon Canal from 1830 to 1836. He also demonstrated a boat using his engine on the Thames in 1827, and an engine-driven carriage in 1828. Father Eugenio Barsanti, an Italian engineer, together with Felice Matteucci of Florence invented the first real internal combustion engine in 1853. Their patent request was granted in London on June 12, 1854, and published in London's Morning Journal under the title "Specification of Eugene Barsanti and Felix Matteucci, Obtaining Motive Power by the Explosion of Gasses". In 1860, Belgian Jean Joseph Etienne Lenoir produced a gas-fired internal combustion engine. In 1864, Nicolaus Otto patented the first atmospheric gas engine. In 1872, American George Brayton invented the first commercial liquid-fueled internal combustion engine. In 1876, Nicolaus Otto, working with Gottlieb Daimler and Wilhelm Maybach, patented the compressed charge, four-stroke cycle engine. In 1879, Karl Benz patented a reliable two-stroke gas engine. In 1892, Rudolf Diesel developed the first compressed charge, a compression ignition engine. In 1926, Robert Goddard launched the first liquid-fueled rocket. In 1939, the Heinkel He 178 became the world's first jet aircraft. In 1954 German engineer Felix Wankel patented a "pistonless" engine using an eccentric rotary design.

Lemuel Wellman Wright was an inventor who was active in the early 19th century. Biographical material on Wright is scant, and even his exact name is unclear: the name Lemuel Wellman Wright is recorded in the British patent index for the patents listed below, but some texts use Lemuel Willman Wright to refer to the author of the same patents. There are contemporary references to an American from Massachusetts, Lemuel William Wright, who patented machinery and created a factory to make pins in London. The patent subject index lists the author of a patent for making pins in 1824 as Lemuel Wellman Wright, and has no other similar names recorded related to pins, so unless the patent office publication is in error, all these references appear to be to the same inventor.

Internal combustion engine Engine in which the combustion of a fuel occurs with an oxidizer in a combustion chamber

An internal combustion engine (ICE) 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 applied typically to pistons, turbine blades, a rotor, or a nozzle. This force moves the component over a distance, transforming chemical energy into useful kinetic energy and is used to propel, move or power whatever the engine is attached to. This replaced the external combustion engine for applications where weight or size of the engine is important.

References

  1. r., H. R. (1933). "Sir Dugald Clerk. 1854-1932". Obituary Notices of Fellows of the Royal Society . 1 (2): 101–102. doi: 10.1098/rsbm.1933.0004 .
  2. 1 2 3 "Forgotten Hero: The man who invented the two-stroke engine". David Boothroyd, The VU. Archived from the original on 15 December 2004. Retrieved 19 January 2005.
  3. 1 2 3 4 Nunney, M.J. (2007). Light and heavy vehicle technology (4th ed.). Oxford, England: Elsevier Butterworth-Heinemann. pp. 6–8. ISBN   978-0-7506-8037-0.
  4. 1 2 3 4 Beecroft, David (2008). History of the American automobile industry. lulu.com. pp. 64–65. ISBN   978-0-557-05575-3.
  5. "No. 13133". The Edinburgh Gazette . 27 August 1917. p. 1785.
  6. https://www.royalsoced.org.uk/cms/files/fellows/biographical_index/fells_indexp1.pdf [ dead link ]
  7. 1 2 3 Dugald Clerk, "Gas and Oil Engines", Longman Green & Co, 1897.
  8. Ian McNeil, ed. (1990). Encyclopedia of the History of Technology . London: Routledge. pp.  315–321. ISBN   0-203-19211-7. rateau engine.
  9. 1 2 3 4 Edgington, David W. (2004). Old stationary engines (2nd ed. revised and updated. ed.). Princes Risborough: Shire. pp. 8–9. ISBN   0-7478-0594-6.
  10. "Goldsmiths Hall, 26 Clerk D". Baz Manning. Retrieved 18 December 2020.