THEORETICAL STUDY OF THE CONTACT BETWEEN SHAPED PEGS AND CORN GRAIN IN A THRESHING CHAMBER

For effective threshing of corncobs, the working elements of modern threshing devices are equipped with steel pegs of various shapes. The design parameters of these studs are determined experimentally, without previous theoretical studies. In this paper, the authors propose the design of a new shaped peg for a corncob threshing device. The design of the new-shaped stud has been obtained on the basis of the analysis of design features of biological prototypes of the studs. It differs from the widely spread round stud by the curvature of its working surface. Mandibles of granary pests (elements of the mouthpiece of insects eating corn kernels) were taken as a biological prototype. The study involved 3D modeling of the contact of a corn grain shell with steel pegs of a widespread round shape and new shaped studs. It has been established that the contact area of the round stpegud and the corn grain shell is an ellipsoid, and the contact area of the new shaped peg and the corn grain shell is a complex figure consisting of an ellipsoid and an elliptical paraboloid. Theoretical studies have been carried out, as a result of which expressions have been obtained for determining the volumes of a grain shell pressed into the inside by a round and a new shaped peg. The contact areas of grains and round and shaped studs have been analyzed in terms of the contact area size and the penetration depth of the peg into the grain. As a result, relative equality of the pressed volumes of a grain shell with both a round and a new shaped peg has been determined and a significant difference in the contact area size has been revealed: for the round peg, the contact area with the corn shell is 3,12 mm2, and the new shaped peg, it amounts to 5,17 mm2. Therefore, when using pegs of a new design, threshing force is spread over a larger area, which reduces the probability of small and large deformations of grain.

зерно кукурузы, обмолот, фасонный шип, биологический прототип, деформация зерна, corn grain, threshing, shaped peg, biological prototype, grain deformation

1. Петунина И.А. Обмолот початков кукурузы. Краснодар: Кубанский государственный аграрный университет, 2006. 206 с.

2. Голик С.М. Механизация уборки, обработки и хранения кукурузы. М.: Колос, 1973. 335 с.

3. Алдошин Н.В., Золотов А.А., Цыгуткин А.С. и др. Уборка бинарных посевов зерновых культур // Вестник ФГОУ ВПО «МГАУ имени В.П. Го-рячкина». 2016. № 3 (73). С. 11-17.

4. Алдошин Н.В., Золотов А.А. Анализ повреждения зерна на уборке белого люпина // Глобализация и развитие агропромышленного комплекса России: Сб. науч. трудов по материалам Межд. науч.-практ. конф., посвященной 110-летию ФГБОУ ВПО СПбГАУ 2014. С. 132-136.

5. Кильчевский Н.А. Динамическое контактное сжатие твердых тел. Удар. К.: Наукова думка, 1976. 357 с.

6. Петухов С.В. Биомеханика, бионика и симметрия. М.: Наука, 1981. 240 с.

7. Бахарев Д.Н., Вольвак С.Ф. Бионические основы разработки и конструирования эффективных шипов молотильно-сепарирующих устройств для кукурузы // Инновации в АПК: проблемы и пер­спективы. 2017. № 3 (15). С. 3-13.

8. Рожывський М.Ф. До визначення мехашз-му деформаци i руйнування зернових матер1а-л1в // Вiсник аграрно! науки. 2000. № 7. С. 50-53.

9. Берд Дж. Инженерная математика. М.: Додека-XXI, 2008. 544 с.

10. Гусак А.А. Справочник по высшей математике. Мн.: ТетраСистема, 1999. 640 с.