• Energy Research

The article contains a comparative analysis of two types of burners used in different methods of fuel-air mixture preparation: (1) vortex mixing and (2) mixing with transverse jets. The analysis was carried out in order to determine which one of the two burning devices is more efficient and has better environmental performance. In device no. 1, conditions for the fuel-air mixture formation are created by vortex turbulence. The basic principle lying at the core of this design is a vortex flow inside, which provokes a more intense mixing of fuel and air. Moreover, preliminary physical and thermal treatment of the fuel-air mixture has a positive effect on its environmental performance. In contrast, in device no. 2 based on transverse jets’ active mixture formation is achieved through collision of air and fuel flows at an angle close to 90°. The research was based on an experiment carried out with the use of a laboratory firing stand. Flue gas samples were analyzed in order to compare the main harmful air emission indicators with TESTO 350-XL gas analyzer. A propane-butane mixture of 60% C3H8 (propane) and 40% C4H10 (butane) was used as the main fuel. Some indicators were determined after the experiment: measurement units conversion from “ppm” to “mg/m3,” excess air ratio α and equivalence ratio φ, flue gas concentrations recalculation taking oxygen into account, fuel calorific value, and heat release rate. The analysis results are as follows: (i) the swirl burner shows better performance in terms of nitrogen oxides (NOx) emissions; there is a 1.75-fold difference in total NOx emissions compared to the cross jet burner; (ii) the burner on transverse jets is 10 times more efficient than the swirl burner in terms of carbon monoxide (CO) emissions.

This report dwells on the scientific study of the vortical device. The device is designed for efficient combustion of fossil fuels. Oil-water emulsion was taken as an example of alternative fuel. Although the functionality of the burner device is not limited to this fuel only. The innovative burner device under investigation is based on principal of vortical motion of fuel air mixture. There is a precombustion chamber specially designed, where inflammation and partial combustion of the swirling flow takes place. The article describes experiment on defining the geometric dimensioning of the burner discharge nozzle in relation to a combustion chamber. The position of the outlet nozzle inside of the burner is the main input parameter of this research. The authors analyzed the influence of this parameter on the pressure inside the combustion chamber and the electric load of the fan for the supplying combustion air. The position ranged from 0 to 120%. The optimal position is at 50% of the total length of the burner chamber. The pressure graph has an extremum in this position, and the electric energy consumption by the fan changes less significantly with further deepening of the output nozzle than earlier. The Results are presented for cold (air blowing only) and hot experiment (burning). This experiment proved the need for the design of the inner part of the discharge nozzle, which is a design feature of the burner device for which the European patent was obtained. The patent link is presented in the list of references.