The present work consists of a validation attempt of an effervescent spray model with secondary atomization.The objective is the simulation of a 1 MW industrial-type liquid fuel burner equipped with effervescent spray nozzle. The adopted approach is based on a double experimental validation. Firstly, the evolution of radial drop size distributions of an isothermal spray is investigated. Secondly, the spray model is tested in a swirling combustion simulation by means of measured wall heat flux profile along the flame. In the first part of the paper,both experimentsare described along with the measuring techniques. Drop sizes and velocities measured using a Dantec phase/Doppler particle analyser are analysed in detail for six radial positions. Local heat fluxes are measured by a reliable technique along the furnace walls in a large-scale watercooled laboratory furnace. In the second part Euler-Lagrange approach is applied for two-phase flow spray simulations. The adopted spray model is based on the latest industrially relevant (i.e. computationally manageable) primary and secondary breakup sub-models complemented with droplet collision model and a dynamic droplet drag model.Results show discrepancies in the prediction of radial evolution of Sauter mean diameter and exaggerated bimodality in drop size distributions. A partial qualitative agreement is found in radial evolution of drop size distributions. Difficulties in predicting the formation of small drops are highlighted. Comparison of the predicted wall heat fluxes and measured heat loads in swirling flame combustion simulation shows thatthe absence of the smallest droplets causes a significant elongation of the flame.

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The preparation of steel substrates coated with intermediate ground and final ceramic coatings is described. The basic material for the preparation of both coatings is the same kind of special glass. The coatings were thermally treated up to 960℃. The resulting substrates were tested for the usage in thick film technology by applying ruthenium resistor compositions designed for use on ceramic substrates. The resistors were fired up to 900℃ and their resistance and TCR were measured. They showed almost the same dependence on firing temperature as the resistors printed on alumina substrates. The TCR was only shifted towards more positive values.

The electrical properties of resistors comprising finely divided CdO and cadmium glass, were investigated. The change in a temperature coefficient of resistance from about -500 ppm/C to +70 ppm/C was realized by addition of a further component to the resistor paste. Differential thermal analysis, X-ray diffraction analysis and scanning electron microscopy were used for studying crystalline phases in glass containing CdO.

New resistor compositions prepared by using special kinds of glass, CdO and ruthenium compound have been developed. The properties of resistors prepared from various compositions were tested in relation to peak firing temperature varying in the range from 760°C up to 850°C. In this way conditions were found for resistor preparation with constant, positive and relatively high TCR (2,500 ppm/°C) and high long‐term stability at 95% relative humidity at 40°C, and with various sheet resistivity (500 ohms/sq.?3,000 ohms/sq.). This system is typical in containing only small amounts of ruthenium compound ranging from 6 wt % to 12 wt %. The resistors can be used for temperature measurement as temperature sensors.