The Application of Similarity Theory and Dimensional Analysis to the Study of Centrifugal-Rotary Chopper of Forage Grain

Wacław Romaniuk,Petr Savinykh,Aleksandr Moshonkin,Alexey Y Isupov,Kinga Borek,Grzegorz Wałowski,Michał Roman,Kamil Roman

doi:10.3390/en14154501

Abstract

This article presents the device and the principle of operation of forage grain crushers that use the centrifugal force of inertia to supply the working bodies—which occurs as a result of rotation of the rotor with a vertical axis. The results of some tests of machines working on this principle have been characterized. Attention is drawn to the disadvantages of most research works, namely the lack of premises for creating shredders of this class with a wide range of performance. The aim of this work is to establish the relationship between the design and technological parameters for the operation of a centrifugal-rotary shredder using the theory of similarity and a dimensional analysis. Moreover, the experimental data show an empirical relationship when calculating the efficiency for the shredder model considered above. By applying the similarity criteria, dimensionless complexes were obtained, which allow to determine the significance of the parameters selected at the initial stage for the efficiency of the shredder. The novelty of this research is the application of the theory of similarity and the use of dimensional analysis, which allowed for scaling the results of the experimental data and obtaining a centrifugal-rotary shredder with higher efficiency, while maintaining the quality of the obtained product. This technique indicates the energy costs of the grinding process, which can be used to select the ratio of parameters in the shredder that would ensure that a minimum amount of energy is consumed.

Highlights

At least 50% of all grain produced in the world is used for the production of feed for farm animals
Having information about the influence of various factors on the operation of the centrifugal-rotary shredder [1,2,3,4,5,6,7,9,14,15,16,17,19,20,21,22,23], we consider them as a set of criteria that affect the performance during the grinding and separation process
The use of similarity theory and dimension analysis allowed us to obtain an empirical dependence for calculating the performance of a centrifugal-rotary grain shredder of the considered design

Summary

Introduction

At least 50% of all grain produced in the world is used for the production of feed for farm animals. In the proposed design of a centrifugal-rotary shredder, the optimal number of cutting elements on the first Z1 = 20 and second Z2 = 30 grinding pairs of ring protrusions of working bodies is justified, allowing to obtain a high-quality finished product with a dust-like fraction not exceeding 5%, which is 5 ÷ 6 times less than after grinding on hammer crushers. It has been established that two adjacent pairs of ring protrusions of working bodies are sufficient to obtain the zootechnically required quality of milling of feed grain and rapeseed; the rational cutting speed (chipping) of grain in a centrifugal-rotary chopper v = (22 ÷ 46) m/s

Objectives

Methods

Results

Conclusion