The development of a biofuels engine testing facility

[摘要] This report covers the development of a biofuels engine testing facility at StellenboschUniversity. The motivation for the project was three fold: a) a desire to establish biofuelsand engine testing know-how; b) to test the performance characteristics of biodiesel; andc) make a facility available for future research. The two main conclusions drawn from theinitial test results are: 1) the test cell is fully operational and 2) biodiesel can besubstituted for mineral diesel. To the author's knowledge this is the first biofuel specificengine testing facility in South Africa.After a literature study the test cell was realised in three phases.• Firstly, the hardware layout was designed and the necessary equipment wassourced from respectable suppliers including the judicious use of good qaulitysecond hand components to minimize capital cost.• The test cell was then instrumented with new sensors. Key components amongthese are the K-type thermocouples, barometric pressure, humidity, oil pressureand an Allen-Bradley programmable controller to serve as a data acquisitioncard. Two software programs were chosen, ETA for the control of the test celland RSLogix to program the programmable logic controller (PLC).• The complete system was then integrated, debugged and validated.The design methods and procedures have been documented throughout the projectalong with user manuals to facilitate further research.To determine the difference in combustion parameters between biodiesel and mineraldiesel an autonomous power curve test was conducted. This revealed little difference interms of performance between the two fuels, although biodiesel had on average amarginal 0.4% decrease in power over mineral diesel. The fuel consumption for purebiodiesel was found to be higher, which is as expected as it is has a lower calorific valuethan mineral diesel.As a final validation, an energy balance was conducted. Here the calculated calorificvalue of biodiesel was compared to the results from a calorie bomb test, and the tworesults were found to be within 2% of each of other.

[发布机构] Stellenbosch University