Malone engine
Encyclopedia
The Malone engine is a liquid-based engine invented by J.F.J Malone of Newcastle
, England
. The engine used high temperature water as its working fluid
, and was therefore also referred to as the Hot Water Engine. Malone's first 50 hp prototype was completed in 1925, and used coal to heat high pressure water sealed inside a cylinder. Malone's second prototype, demonstrated in 1931, also produced 50 hp but in a much smaller design.
In independent testing the design showed an astounding efficiency
of 27%, which exceeded the efficiency of steam engine
s of the day and approximately equalled the efficiency of a gasoline engine.
The cycle used by the Malone engine is a modified version of the Stirling Cycle
. The sealed cylinders filled with water are heated from one end to a temperature above the boiling point
of water, but because of the limited volume within the cylinder the water can not change phase. Instead, the water expands, in the process pushing the piston inside the cylinder. The opposite end of the cylinder is cooled by the air, or alternatively a coolant fluid, and thus the cylinder compresses once more, completing the Stirling cycle.
Newcastle upon Tyne
Newcastle upon Tyne is a city and metropolitan borough of Tyne and Wear, in North East England. Historically a part of Northumberland, it is situated on the north bank of the River Tyne...
, England
England
England is a country that is part of the United Kingdom. It shares land borders with Scotland to the north and Wales to the west; the Irish Sea is to the north west, the Celtic Sea to the south west, with the North Sea to the east and the English Channel to the south separating it from continental...
. The engine used high temperature water as its working fluid
Working fluid
A working fluid is a pressurized gas or liquid that actuates a machine. Examples include steam in a steam engine, air in a hot air engine and hydraulic fluid in a hydraulic motor or hydraulic cylinder...
, and was therefore also referred to as the Hot Water Engine. Malone's first 50 hp prototype was completed in 1925, and used coal to heat high pressure water sealed inside a cylinder. Malone's second prototype, demonstrated in 1931, also produced 50 hp but in a much smaller design.
In independent testing the design showed an astounding efficiency
Energy conversion efficiency
Energy conversion efficiency is the ratio between the useful output of an energy conversion machine and the input, in energy terms. The useful output may be electric power, mechanical work, or heat.-Overview:...
of 27%, which exceeded the efficiency of steam engine
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...
s of the day and approximately equalled the efficiency of a gasoline engine.
The cycle used by the Malone engine is a modified version of the Stirling Cycle
Stirling cycle
The Stirling cycle is a thermodynamic cycle that describes the general class of Stirling devices. This includes the original Stirling engine that was invented, developed and patented in 1816 by Reverend Dr...
. The sealed cylinders filled with water are heated from one end to a temperature above the boiling point
Boiling point
The boiling point of an element or a substance is the temperature at which the vapor pressure of the liquid equals the environmental pressure surrounding the liquid....
of water, but because of the limited volume within the cylinder the water can not change phase. Instead, the water expands, in the process pushing the piston inside the cylinder. The opposite end of the cylinder is cooled by the air, or alternatively a coolant fluid, and thus the cylinder compresses once more, completing the Stirling cycle.