Affiliation:
1. College of Science and Technology, University of Manchester.
Abstract
The results are given from a comprehensive investigation of the exhaust pipe configurations for five-, six-, seven-and eight-cylinder turbocharged two-stroke engines. The tests were carried out under cold conditions on a multi-cylinder pulse generator. For each engine two firing orders and the maximum number of alternative pipe arrangements compatible with minimum interference between cylinders were examined. Three nozzle sizes were tested for each basic configuration. The test results were analysed to determine the maximum efficiency of the exhaust pipe, expressed as the availability factor, the average scavenge ratio and the distribution of retained air between cylinders. Results of the investigation showed that in the multi-cylinder system the scavenge ratio increased with increase in nozzle area ratio, increase in the number of cylinders discharging into the pipe system, and with decrease in pipe length. The gas retained in the cylinders was found to increase with decrease in nozzle area to pipe area ratio and decrease in pipe volume. The availability factor was found to increase with decrease in nozzle area to pipe area ratio and decrease in pipe volume.