Still engine
Encyclopedia
The Still engine was a piston engine
that simultaneously used both steam power
from an external boiler
, and internal combustion from gasoline
or diesel, in the same unit. The waste heat from the cylinder
and internal combustion exhaust was directed to the steam boiler, resulting in claimed fuel savings of up to 10%.
inventor Charles Algernon Parsons
, at the Royal Society of Arts
. Still described a continuous process by which a double-acting cylinder
is powered on one side by internal combustion and on the other by steam from a boiler heated principally by the waste heat from the water jacket and exhaust gases. He explained how the reserve of energy represented by the steam pressure in the boiler provided for any occasional overload which would defeat a standard internal combustion engine of the same power. Independent heating of the boiler was occasionally used, to provide extra power for exceptional conditions, and in the first stage of operation to allow the engine to start itself from steam power alone, even against a load.
of Greenock, Scotland, put a diesel-fuelled marine version, the Scott-Still regenerative engine, into production, with the first pair of engines installed in the twin-screw M. V. Dolius. The requirement to carry marine engineering officers certified with both steam and motor qualifications, meaning extra crew members and wages, and the extra complexity with consequent higher maintenance costs, offset the fuel savings and conventional diesel engines were later installed in their place.
In 1926 Kitson and Company, locomotive builders of Leeds, England, produced a steam–diesel hybrid locomotive, the Kitson Still locomotive
. This was loaned for trials to the London and North Eastern Railway
and used successfully to haul heavy coal trains, but the difference in the cost of coal used by a conventional locomotive, against the fuel oil used by the hybrid, was not great. When Kitson's failed in 1934, a failure to which the development costs of the hybrid locomotive had contributed, the receivers
sold the machine for scrap.
Developments of larger diesel engines in the 1930s, with improved methods of power transmission
, meant that a principal advantage of the Still engine – the ability to provide additional power for starting and temporary high load – was lost, and further development ended.
Reciprocating engine
A reciprocating engine, also often known as a piston engine, is a heat engine that uses one or more reciprocating pistons to convert pressure into a rotating motion. This article describes the common features of all types...
that simultaneously used both steam power
Steam engine
A steam engine is a heat engine that performs mechanical work using steam as its working fluid.Steam engines are external combustion engines, where the working fluid is separate from the combustion products. Non-combustion heat sources such as solar power, nuclear power or geothermal energy may be...
from an external boiler
Boiler
A boiler is a closed vessel in which water or other fluid is heated. The heated or vaporized fluid exits the boiler for use in various processes or heating applications.-Materials:...
, and internal combustion from gasoline
Gasoline
Gasoline , or petrol , is a toxic, translucent, petroleum-derived liquid that is primarily used as a fuel in internal combustion engines. It consists mostly of organic compounds obtained by the fractional distillation of petroleum, enhanced with a variety of additives. Some gasolines also contain...
or diesel, in the same unit. The waste heat from the cylinder
Cylinder (engine)
A cylinder is the central working part of a reciprocating engine or pump, the space in which a piston travels. Multiple cylinders are commonly arranged side by side in a bank, or engine block, which is typically cast from aluminum or cast iron before receiving precision machine work...
and internal combustion exhaust was directed to the steam boiler, resulting in claimed fuel savings of up to 10%.
History
The inventor, William Joseph Still, patented his device in 1917 and on 26 May 1919 in London he announced it at a meeting, chaired by steam turbineSteam turbine
A steam turbine is a mechanical device that extracts thermal energy from pressurized steam, and converts it into rotary motion. Its modern manifestation was invented by Sir Charles Parsons in 1884....
inventor Charles Algernon Parsons
Charles Algernon Parsons
Sir Charles Algernon Parsons OM KCB FRS was an Anglo-Irish engineer, best known for his invention of the steam turbine. He worked as an engineer on dynamo and turbine design, and power generation, with great influence on the naval and electrical engineering fields...
, at the Royal Society of Arts
Royal Society of Arts
The Royal Society for the encouragement of Arts, Manufacturers and Commerce is a British multi-disciplinary institution, based in London. The name Royal Society of Arts is frequently used for brevity...
. Still described a continuous process by which a double-acting cylinder
Double-acting cylinder
A double-acting cylinder in a reciprocating engine is a cylinder in which the working fluid acts alternately on both sides of the piston. This is in contrast to a single-acting cylinder, in which the working fluid acts in one direction only....
is powered on one side by internal combustion and on the other by steam from a boiler heated principally by the waste heat from the water jacket and exhaust gases. He explained how the reserve of energy represented by the steam pressure in the boiler provided for any occasional overload which would defeat a standard internal combustion engine of the same power. Independent heating of the boiler was occasionally used, to provide extra power for exceptional conditions, and in the first stage of operation to allow the engine to start itself from steam power alone, even against a load.
Development
In 1924 Scotts Shipbuilding and Engineering CompanyScotts Shipbuilding and Engineering Company
Scotts Shipbuilding and Engineering Company Limited, often referred to simply as Scotts, was a Scottish shipbuilding company based in Greenock on the River Clyde.- History :...
of Greenock, Scotland, put a diesel-fuelled marine version, the Scott-Still regenerative engine, into production, with the first pair of engines installed in the twin-screw M. V. Dolius. The requirement to carry marine engineering officers certified with both steam and motor qualifications, meaning extra crew members and wages, and the extra complexity with consequent higher maintenance costs, offset the fuel savings and conventional diesel engines were later installed in their place.
In 1926 Kitson and Company, locomotive builders of Leeds, England, produced a steam–diesel hybrid locomotive, the Kitson Still locomotive
Steam diesel hybrid locomotive
A steam diesel hybrid locomotive was a railway locomotive with a piston engine which could run on either steam from a boiler or diesel fuel. Examples were built in the United Kingdom, Russia and Italy but the relatively high cost of fuel oil meant that the designs were not pursued.-Kitson-Still...
. This was loaned for trials to the London and North Eastern Railway
London and North Eastern Railway
The London and North Eastern Railway was the second-largest of the "Big Four" railway companies created by the Railways Act 1921 in Britain...
and used successfully to haul heavy coal trains, but the difference in the cost of coal used by a conventional locomotive, against the fuel oil used by the hybrid, was not great. When Kitson's failed in 1934, a failure to which the development costs of the hybrid locomotive had contributed, the receivers
Receivership
In law, receivership is the situation in which an institution or enterprise is being held by a receiver, a person "placed in the custodial responsibility for the property of others, including tangible and intangible assets and rights." The receivership remedy is an equitable remedy that emerged in...
sold the machine for scrap.
Developments of larger diesel engines in the 1930s, with improved methods of power transmission
Transmission (mechanics)
A machine consists of a power source and a power transmission system, which provides controlled application of the power. Merriam-Webster defines transmission as: an assembly of parts including the speed-changing gears and the propeller shaft by which the power is transmitted from an engine to a...
, meant that a principal advantage of the Still engine – the ability to provide additional power for starting and temporary high load – was lost, and further development ended.