This paper presents a flowmeter design applicable for measurement of low gas flow amounts. The designed flowmeter with a time – of – flight sensor represents a microcomputer application with a control and evaluation procedure. The mathematical model of energy and temperature balance is simulated in the FEMLAB environment. The designed measurement device was used for research of reaction kinetics of biodegradation reactions successfully.

Ultrasound process tomography is a method for imaging the acoustic impedance or sound velocity distribution within a closed pipe or vessel. It can be used for the determination of process parameters, like flow rates and material fractions, in industrial multi-phase flows. Many approaches are based on reflection measurements and the assumption of piece-wise constant acoustic impedance distributions. For this configuration we present a novel iterative approach for image reconstruction. Reflecting objects, like gas bubbles, are modeled by B-spline contours. The inverse problem of determining the object position and shape from the reflection measurements at the boundary of the vessel is solved using a quasi-Newton optimization algorithm. The forward problem, i.e. the simulation of the measurement given the object parameters, is solved using an efficient formulation based on Fermat’s principle. The model-based approach offers the advantage of always yielding closed contours. Both reflection and transmission measurement data can be used in a unified manner. The feasibility of the approach is demonstrated using simulated data.

Dual fueled engine test procedures and result interpretation are not available in the literature, This paper describes a methodology for calculating the emission mass flow rates, using the chemical reaction mass balance of the components. The experimental data were obtained from tests made at the MWM dynamometer. Starting from basic principles, the hydrocarbon (HC) mass flow rate was related to molar concentration through the molecular mass and the exhaust gas mass flow rate, and compared to the available expressions in the EPA diesel engine test standard. The dual fuel model was established by a linear combination for the hydrocarbon (HC) equivalent molecular mass, when there is 0 % and 100 % natural gas in the fuel. Finally, the paper shows that, by a similar methodology, the natural gas mass flow rate can be calculated from emission measurements.

New principle of the particle size distribution measurement is described. We analyze acoustic emission signal generated by a flow of particles impacting on a fixed obstacle. Changes of the power spectral density of the signal are well correlated with the particle size distribution. Our method was successfully used for measurement of particle size distribution in the range from 1mm to 10 mm of the ferrous sulphate monohydrate in real chemistry process. Particles were measured at the output of the dry kiln (temperature 150-200 °C, mass flow 4 tons/hour), where it is not possible to use any of other known principles such as particle vision, laser diffraction analyzers, ultrasonic analyzers, focused-beam reflectance measurement etc.

The purpose of this study is to estimate the uncertainty contribution due to the diverter valve in the total uncertainty, concerning the calibration of flow meters in the water laboratory of the Center for Fluid Metrology.