Pure aerodynamics: Great pat of practically relevant fluid flow computations involves just the basic flow physics, i.e. turbulence and possibly convective heat transfer. These computations serve to quantify a range of parameters including e.g. the intensity of suction (entrainment), flow splitting into parallel branches, flow non-uniformity over a cross-section, intensity of mixing streams, or temperature distribution. Our tasks include also analysis and optimisation of ejector pumps or heat exchangers.

Combustion chambers: Fluid flows involving chemical reactions, formation and abatement of pollutants, as well as radiative heat transfer are one of demanding types of problems on which we specialize in our academic research. The expertise collected through these activities is offered to our commercial customers. These computations are used in analysis of high-end applications as for example tubular furnaces, boilers, secondary combustion chambers or industrial burners.

Burners (gas and liquid): Simulations typically include also heat transfer and pollutants formation (mainly NOx) in the combustion chamber. Research in modelling of burners is focusing on the methodology for predicting performance of industrial burners (firing mainly gas, but also liquid fuels), which yields reliable predictions of heat loading to the walls of combustion chamber or boiler. In this work, we lean on data collected in an advanced burner testing laboratory, which features a uniquely designed combustion chamber and extensive instrumentation, enabling to accurately measure wall heat flux profile along the flame. In commercial projects involving combustion analysis, heat loading of walls is of primary importance. For these projects we offer large experience and validated models.

Grate combustion of biomass: The task involves a description of processes occurring in the fixed bed of solid fuel, e.g. wood chips or other fuel, on the grate in a combustion chamber. The solution of processes in the solid fuel layer by an in-house code GRATECAL is coupled to a combustion model in the freeboard of boiler, which is set up in ANSYS FLUENT. These two models (bed and freeboard) have to exchange information in each iteration of the computation, describing the exchange of heat and mass on the boundary between them. The bed model is created through orthogonal discretization using finite volume method.

Heat exchangers: Computational fluid dynamics is used mainly to predict performance parameters of new or redesigned heat exchangers, for which reliable design correlations are unavailable. Troubleshooting for poor performance or failures is a frequent task, as well as checking redesigned heat exchangers. This motivation for CFD analysis is common in other applications too, but specifically in heat exchangers it often entails balancing of flow distribution.

Wet scrubbers: Cleaning of flue gas using Venturi scrubber is often used e.g. in waste incinerators, design is however often based on rough estimates. This practice has impact on the separation efficiency, as well as on pressure drop which is significant and causes high operating costs. Modelling of wet scrubbers by computational fluid dynamics in connection with experimental research has led to a methodology for performing design verification calculations for these units. Besides Venturi scrubber our research was focused on a „new type of scrubber“: veda-vyzkum/experi­mentalni-zakladna-dvoustupnove-absorpcni-cisteni-spalin, which provides the same separation efficiency with lower pressure drop.

Industrial fabric filters: Operation of filters has two main regimes – working and cleaning regime, in which a layer of collected particles (cake) is removed from the filter surface. The filter cleaning efficiency may be influenced by special inserts of the filter bags, which however also increase pressure drop during the working regime. Subject of the research was quantification of the working and cleaning characteristics of the inserts.