The article presents the procedure for how to establish a mathematical model of nitrogen oxides formation based on the theory of dimensional analysis. The model is based on selected physical quantities (parameters) measurable during regular operation of a heat generation plant. The objective of using dimensional analysis to describe nitrogen oxides formation is to show that between operating parameters of the combustion equipment and the NO x formation there is a significant correlation. The obtained results, which are further described in this article, have proved this fact.The obtained formula expressing nitrogen oxides formation, based on dimensional analysis, applies universally to any boiler fuelled by coal, gas or biomass. However, it is necessary to find C, m, n constants for the formula by experiment, individually for each type of boiler and used fuel. The experiment is based on on-line measurements of selected operational parameters for a given boiler, combusting a certain type of fuel with its actual moisture content and calorific value. The methodology, described in this article, helps to find relationships between the operational parameters and the formation of NO x emissions for a particular furnace. The developed mathematical model has been validated with boilers fuelled by black coal and biomass. Both the results obtained from direct measurements of NO x in both types of boilers, and the results obtained by calculation using equation based on the dimensional analysis, are in a very good accord. When burning coal, the variation between NO x expression from the model and the on-line measurements ranges between -12.23 % and + 9.92 %, and for burning biomass between -0.54 % and 0.48 %.The intention of the authors is to inform the professional community about the suitability of the dimensional analysis to describe any phenomena for which there is currently no exact mathematical formulation based on differential equations or empirical formulas. Many other examples of dimensional analysis applications in practice may be found in the work of Čarnogurská and Příhoda (2011).
An original method for estimating fouled deposit thickness on the inside surfaces of natural gas cooler tubes is presented. This method does not require opening and inspecting a cooler as it is based on the measurement of gas cooling degree, i.e. the gas temperature difference between the cooler inlet and discharge. The deposit layer on the internal heat transfer surfaces is of semi-liquid consistency and its thermal conductivity coefficient has not been investigated until now. This paper describes the experimental determination of the deposit thermal conductivity coefficient. This parameter enables determination of a cooler's performance as a function of current deposit thickness. Practical application of the method is illustrated in the case of CH_R cooler working in the KS01 compressor station in Veľké Kapušany, Slovakia. For this type of cooler, a diagram for deposit thickness as a function of the gas cooling degree is presented.
Abstract:The present article describes the diagnostics of a compressor that is compressing a mixture of H 2 and N 2 on the basis of the results that were obtained by operational measurements of the flow rates and temperatures at selected compressor sites, as well as of the acoustic pressure levels during the full loading thereof. The obtained data were subsequently used to determine the limit conditions of the compressor operations in terms of the cooling capacity. A thermodynamic analysis of the compression of the H 2 /N 2 gas mixture was carried out with subsequent heat and energy flow calculation and the determination of the minimum cooling water flow rate that is required to ensure the continuous compressor operations.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.