Ramadan, O., Webster, G., Menard, L., Wilcox, A. et al., "Ignition Quality Tester (IQT™) Precision Improvements from Using the Totally Automated Laboratory Model (TALM) Technology: Technology Update, Part-2: Mini Inter-Laboratory Study Using the IQT™-TALM," SAE Technical Paper 2015-01-0805, 2015, doi:10.4271/2015-01-0805.
This paper presents the results of a mini Inter-Laboratory Study (mILS) that is a continuation of earlier work, published in SAE paper number 2014-01-0179 . This work was aimed to improve the capability, precision, and durability of the Ignition Quality Tester (IQT™) and ASTM D6890 /EN15195  Test Methods. The mILS was performed to determine how much the TALM IQT™ Precision Package would improve the precision of four IQT™s, relative to a larger number of IQT™s participating in two separate Fuel Exchange Programs (FEPs). Two of the IQT™s were located at AET and the other two were located at two different external laboratories. All four IQT™s were equipped with the TALM Precision Package. Nine fuel samples from the two FEPs with reference DCN values from 33 to 82 were selected for testing. The parameters investigated were: 1) The difference between the average DCN values of the fuel samples and their reference values. 2) The difference between the average standard deviation of DCN values of the fuel samples and their reference values. 3) Effect of mILS results on D6890 method reproducibility and comparison with other Cetane standard test methods. An overall improvement of 63% in the average standard deviation of DCN values was found relative to the reference values reported in the ASTM NEG and the EI CS FEPs. When the mILS results were compared with the average standard deviation of CN reference values reported in the same FEP, the overall improvement was 73%. Over the DCN range of 33 to 70, the mILS results indicate a 53% to 71% improvement in reproducibility compared to the reproducibility published in EN 15195-14 . These results provide an indication of how the addition of the TALM Precision Package to an IQT™ can markedly improve the precision of the IQT™.