Analysis of mud splashing pattern of paddy field blade using computational fluid dynamics

Abstract

This study provides a systematic investigation of the mud splashing pattern of a paddy field blade specially designed for placing mud in seedling trays to accelerate rice production. To investigate mud splashing patterns that can satisfy the requirements of the seedling-raising operation as well as provide energy savings, computational fluid dynamics simulations combined with experimental methods were adopted in this study. Moreover, evaluation indexes of the transient mud splashing volume efficiency (ηmv) and mud splashing distance efficiency (ηmd) were proposed and calculated to analyse the performance of the paddy field blade during mud splashing. Comparisons between the model predictions and the experimental measurements showed that the numerical model could acceptably predict the splashing volume and power consumption. The results reveal that muds with different water contents in the paddy field have considerably different rheological properties. The water content of the mud has a negligible effect on the splashing pattern but is closely related to the magnitude of the power consumption. High rotation speeds result in a relatively low value of ηmv; however, ηmv decreases slightly as the rotation speed increases from 50 to 60 rad/s. The value of ηmd is found to increase with increasing water content of the mud. A rotation speed of 50–60 rad/s is found to be suitable for the proposed seedling tray design. The findings of this study can accelerate the theoretical maturity of blade mud splashing and serve as a valuable resource for mechanising seedling-raising operations.