Validation of methods for controlling the performance characteristics of fuels and motor oils

Relevance . The development of methods for controlling materials, products, substances and the natural environment should be completed by the validation stage. There is a well-known list of validation characteristics and recommendations for their evaluation for methods of controlling the composition of materials, products, substances and the natural environment. However, these descriptions and recommendations cannot be fully used in the case of methods for controlling the properties of materials, products, substances and the natural environment, in particular, the performance characteristics of fuels and motor oils. The purpose. Development of a procedure for validating methods for controlling the performance characteristics of fuels and motor oils and confirming the possibility of its practical implementation. Methods . The practical verification of the theoretical provisions was carried out during the validation of the method for controlling the thermal and oxidative stability of jet engine fuels under dynamic conditions. The essence of the method is to estimate the amount of deposits formed during the oxidation of fuel for jet engines under conditions of its pumping through an annular channel along a heated evaluation tube located inside the channel. Oxidation products accumulate as deposits on the surface of the evaluation tube, reducing its reflectivity, and on the filter element of the control filter, increasing the pressure drop on the control filter. Thermal and oxidative stability is monitored according to the following indicators: thermal stability index, the temperature at which deposits form, and the rate of pressure drop across the filter. The method is implemented on the basis of the DTS-4 laboratory installation. Results . Based on the specifics of the procedure and the controls used, a set of validation characteristics of methods for monitoring the operational properties of fuels and motor oils is proposed: precision and accuracy of the control method; suitability of controls; range of values of controlled quantities; sensitivity of the control method to changes in the composition of fuel (oil); robustness of the method to small changes in control parameters; comparison of the newly developed method with already known methods having a similar functional purpose; the quality of modeling of the studied chemmotological process. To increase the efficiency of validation work, it is advisable to provide an additional stage for the development of a control sample with constant, guaranteed reproducible values characterizing the performance properties of motor fuels and oils (the internal standard of the control method). Conclusion . The experience of validating the DTS-4 method shows that the developed procedure for validating methods for monitoring the performance characteristics of fuels and motor oils ensures that a sufficient amount of objective data is obtained that the new control method allows obtaining reliable information about a given operational property of the studied petroleum product.