Optimization of angular velocity of drum mixers

Abstract

Drum mixers ensure a high level of uniformity when mixing the components of feed additives. However, the issues on theoretical and experimental substantiation of the structural and kinematic parameters of drum mixers have not been scientifically explored in detail. The aim of this study is to improve the efficiency of producing feed mixtures by ensuring the optimal angular rotation velocity of a drum mixer.To determine the radial speed of a particle’s motion along a drum blade, we solved a homogeneous differential equation. The numerical value for angular velocity was determined by a computer simulation method. We experimentally studied the uniformity of redistribution of feed components in a mixture of fodder using the designed experimental drum mixer. The mixer included a chamber, a rectangular frame, a supporting frame, and a drive. The mixing chamber included a loading/unloading window with a closed lid. Radial blades were installed inside the chamber along its entire length and evenly along the perimeter.Experiments were conducted using a drum mixer with a drum radius of 0.17 m, which included radial blades with a width of 25 mm, with a chamber’s fill factor of 0.5. It was established that the drum mixer ensures the maximum scattering of a material’s particles on the surface of the working segment at the drum’s angular rotation velocity of 9.69 rad/s.The results of experimental research have established that at rotation frequency of the laboratory plant’s drum of 9.42 rad/s the uniformity of mixture is 92.5‒93 %, which meets acting zootechnical requirements for all types of mixed fodder. In this case, a maximum deviation of the theoretical and experimental data was about 9 %. The results obtained suggest the possibility of determining a numerical value for the angular velocity of drum mixers by using the proposed method of computer simulation.