A New Internal Combustion Engine Configuration: Opposed Pistons with Crank Offset

Malpress, R. and Buttsworth, D. R. (2007). A New Internal Combustion Engine Configuration: Opposed Pistons with Crank Offset. In: Peter Jacobs, Tim McIntyre, Matthew Cleary, David Buttsworth, David Mee, Rose Clements, Richard Morgan and Charles Lemckert, 16th Australasian Fluid Mechanics Conference (AFMC). 16th Australasian Fluid Mechanics Conference (AFMC), Gold Coast, QLD, Australia, (1258-1265). 3-7 December 2007.

Attached Files (Some files may be inaccessible until you login with your UQ eSpace credentials)
Name Description MIMEType Size Downloads
Malpress_afmc_16_07.pdf Conference Paper Click to show the corresponding preview/stream application/pdf 885.29KB 5478
Author Malpress, R.
Buttsworth, D. R.
Title of paper A New Internal Combustion Engine Configuration: Opposed Pistons with Crank Offset
Conference name 16th Australasian Fluid Mechanics Conference (AFMC)
Conference location Gold Coast, QLD, Australia
Conference dates 3-7 December 2007
Proceedings title 16th Australasian Fluid Mechanics Conference (AFMC)
Place of Publication Brisbane, Australia
Publisher School of Engineering, The University of Queensland
Publication Year 2007
Year available 2007
Sub-type Fully published paper
ISBN 9781864998948
Editor Peter Jacobs
Tim McIntyre
Matthew Cleary
David Buttsworth
David Mee
Rose Clements
Richard Morgan
Charles Lemckert
Start page 1258
End page 1265
Total pages 8
Collection year 2007
Language eng
Abstract/Summary Theoretical and experimental performance results for a new internal combustion engine configuration are presented in this paper. The engine is a piston ported, spark ignition petrol engine which consists of two opposed pistons in a single cylinder controlled by two synchronously timed crankshafts at opposite ends of the cylinder. It makes use of crank offset to create the required piston motion aimed at engine efficiency improvements through thermodynamic performance gains. In particular, the engine employs full expansion in which the power stroke displaces a larger volume than the compression stroke, thereby allowing the expanding gas to reach near atmospheric pressure before the exhaust port opens. This allows more work to be done by each thermodynamic cycle. It also features a greater rate of volume change after combustion than a convention 4-stroke engine for the same crank speed. This reduces the time that the temperature difference between the gas and the cylinder is high relative to a conventional engine which in turn, should reduce the heat lost from the combustion products. Thermodynamic and friction modelling of the engine indicated that efficiencies around 38% might be achieved. However, experiments with a prototype engine demonstrated that friction losses in the engine exceeded that predicted in the original modelling.
Subjects 290799 Resources Engineering not elsewhere classified
Q-Index Code E1
Q-Index Status Provisional Code
Institutional Status Non-UQ

Version Filter Type
Citation counts: Google Scholar Search Google Scholar
Access Statistics: 1129 Abstract Views, 5616 File Downloads  -  Detailed Statistics
Created: Wed, 19 Dec 2007, 15:01:27 EST by Laura McTaggart on behalf of School of Engineering