The horizontally opposed type Stirling Engine's Page


This engine is alpha-type configuration and arranged 2 power pistons opposed horizontally. In this arrangement, distances of between any elements (piston, heat exchanger etc.) are been minimum, thus this engine has less of dead spaces and pressure loss of the working gas. This is one of the most historical experimental Stirling Engine in our laboratory.

Target of development

When we start research of Stirling Engines, in order to make this qualitative characteristic of Stirling engine obvious, design of this engine and trial production was done. We had chosen "horizontally opposed arrangement" because it's match with manufacturing, any experiments, analysis and so on.

The history

This engine was experimentally employed in various ways as the only experiment machine in the early time, left the various results. Though it was heated with the electric heating wire that we wind and attach at first, it cooperated with a general-purpose small-sized gasoline engine later, add it and was driven also to consider the exhaust gas as heat-source. It had took in new trial of the engine elements for example piston ring, link mechanism, heat exchanger and so on. And from various experimental data of this engine, new performance analysis methods were created, any factors of Stirling Engine were examined and optimal design method was built up. The results are widely adopted for engines after that, and become foundation of design and trial production of various experimental machines that there is at present.

Constracture of the horizontally opposed type Stirling Engine

This is a alpha-type construction Stirling engine. The arrangement is horizontally opposed type which have disposed expansion space, heat exchanger and compression space in a line. It has cross-head type crank mechanism at expansion and compression shafts, and each cranks link with timing belt. It is heated by electric heating wire and cooled by water.

Main specifications
Stroke volumeexpanssion space157cm<3 Bore*Stroke:50*80mm
Compression space157cm3 Bore*Stroke:50*80mm
Heat exchangerHeatermulti hole、Shell and tube、Internal heat 
RegeneratorLaminated brass mesh cloth:50 sheets
CoolerShell and tube cooler:103 tubes

Stracture for experiment of heater

Structure of this engine can insert a heater and a regenerator with cartridge style inside a expansion cylinder liner and a cooler also is contained in a compression cylinder liner similarly. Thus heat exchangers and measuring equipment are easy changeable.
A heater had much reformed especially because this engine was experimentally employed variously. There are "inside heating type" to arrange heating wire to coil formed inside a heater, "mullet-hole type" to open a lot of holes to a brass column, "shell-and-tube type" to use the case that we consider exhaust gas as heat-source. On experiment to measure radiation loss from the engine, heat flow meter was installed to "inside heating type" heater of it.

Multi hole heater

Shell and tube heater

Internal heating heater

Performance of the horizontally opposed type Stirling Engine (an example)

This engine is the oldest one and because it was employed variously experiments, so plenty of number experimental data have remained. As we tried to analyze their results, understood for that a shaft power was small as compared with the work that gas did. The great importance cause is a timing belt which links two cranks. Unexpected, became it making obvious that this belt has become plenty of loss.

Conditions on an experiment
Fase difference90 degree
Compression ratio2.49
Supply heat mass1 kW constant
Heatingelectric heating wire
Buffa pressureatmospheric

Various experimental data

Relation of speed and power(actual/analysis)

Comparison of power with heater difference

Comparison of in/outlet temperatures of heat exchanger with heater difference

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