An Attempt to Recompute ECN in the FCA Instrument
In a marine diesel engine, where residual heavy fuels are used as fuel, ignition and combustion are two very important properties that will determine how much of the thermal energy in the fuel is converted into useful work. Till recently, the only parameter used to determine the ignition quality of the fuel has been CCAI (Calculated Carbon Aromaticity Index). Since this was considered inadequate, and outdated, the search for an alternate method resulted in a Fuel Combustion Analyzer Instrument (FCA). The instrument gives out an Estimated Cetane Number (ECN) based on the main combustion delay (MCD), an ignition parameter obtained from the test that represents the ignition and combustion properties of the fuel. Residual fuels with small quantities of lighter fractions have 2 clear phases namely ignition and combustion during the burning process in a diesel engine. After testing hundreds of samples using this instrument, certain anomalies were noted. These include very low ECN values in fuels from Santos, Brazil that did not experience any problems during actual running and fuels with higher ECN have causing machinery problems. This could be mainly because of the current ECN calculation which is totally influenced by the ignition properties and somewhat oblivious to the combustion properties of the fuel. A new computation for ECN is suggested by Viswa Lab which includes additional parameter such as MCR, and also additional data from the FCA instrument. This New Estimated Cetane Number (NECN) is currently being validated with additional data points and information from ships on the performance of the fuel in the actual marine diesel engine.
Lakshmi Vedala Sriram Chandrasekhar Ramaratnam Visweswaran
Viswa Lab,USA
国际会议
上海
英文
1-8
2013-05-13（万方平台首次上网日期，不代表论文的发表时间）