Development of Dedicated Lubricant for Hydrogen Fuelled Spark Ignition Engine 2019-28-2511
Hydrocarbon based fossil fuels are being used as the main energy resource, burning of which produces carbon dioxide (CO2) and other emissions harmful to environment. Moreover, CO2 is considered as the main contributor to global warming or greenhouse effect. These are the main drivers behind the ongoing research & development in the area of alternative energy sources. Among various alternatives, Hydrogen is identified as the most promising alternative fuel. Hydrogen is the cleanest fuel having some of the most attractive features such as various methods of production from renewable energy (solar, wind, biomass etc.), from fossil fuels etc. H2 as a fuel can be used in various applications such as spark ignition engine, fuel cells etc.
Hydrogen has low ignition energy and ensures easy ignition of the ultra-lean mixture with air. The flame speed of hydrogen is about five times higher than methane and gasoline which allows hydrogen fuelled IC engines to have relatively reduced cyclic variations than that of with methane and gasoline. High flame speed also helps to make the combustion closer to constant volume which enhances the thermal efficiency of hydrogen fuelled IC engine. High octane of hydrogen makes it suitable as a fuel for Spark ignition (SI) engines. Since the hydrogen combustion in spark ignition engine generates water which can interfere with the lubricant performance, different lubricant is to be developed for this purpose. In this background, the present work is aimed at the development of dedicated lubricant for hydrogen fuelled SI engine.
This paper presents the various parameters required for evaluating different lubricants for hydrogen fuelled genset. Existing CNG genset has been converted into hydrogen genset. State of the art electrical load bank panel system having PLC based automation with data logging provision for accurate measurement of testing parameters is used. It is suitable to apply desirable load in a balanced manner for adequate genset loading with minimised fluctuations.
Three different lubricants were evaluated with respect to emissions such as CO, HC, NOx, Particulates, fuel consumption, BSFC etc. at different loads. Loads were increased in the interval of 1kW/step upto 10 kW. Lubricants were selected based on different chemistry, composition and ash content required for hydrogen fuelled SI engine. CO, HC, particulate emissions of varying diameter are observed even in carbon-less fuel vehicle due to the combustion of lube oil in engine. This effect of lube oil was studied in detail to determine the intensity of emissions produced in the engine since hydrogen has a very less particulate emission. The life of lubricant was established as it is prone to blow-by having high moisture content.