Finite element analysis - applications in agricultural engineering

Abstract

Numerical modelling is becoming an increasingly important tool for analyzing complex problems in the agricultural engineering related problems. Numerical models, particularly the finite difference and finite element methods, were extensively used for modelling such a complex systems. A finite element formulation of two-dimensional groundwater flow and heat transfer problems were developed and a Visual C++ program is used for this purpose to obtain primary unknowns hydraulic head and temperature at the nodes. The domain of the problem was discretized into linear triangular elements. The numerical solutions were obtained for groundwater flow considering pumping and recharge and heat transfer in an isotropic rectangular region. By the analysis of the hydraulic head solution results, one can easily obtain the flow direction vectors, flow velocities and flow rates in different directions and in the same way nodal temperatures can be used to obtain heat flow rates, thermal flux and thermal gradient. ANSYS is a general purpose engineering simulation software package based on the finite element analysis, allowing engineers to refine and validate designs at a stage when cost of making changes is minimal. ANSYS simulation software can predict how product design will operate and manufacturing processes will behave in real world environments. The analysis in ANSYS consists of three steps the pre-processing, the analysis and the post-processing. By post-processing the obtained results can be presented in a desired form. In this work two problems were analysed using ANSYS, the heat transfer in an isotropic medium and the stress analysis of a sub-soiler. The results obtained by finite element program developed for the heat transfer problem is compared with ANSYS results and also analytical results and results are found to compare well. From the stress analysis of the sub-soiler, it is found that the stress near the upper two holes of the sub-soiler is very small and so the upper two holes can be avoided. FEM improve accuracy, enhance the design and better insight into critical design parameters, virtual prototyping, fewer hardware prototypes, a faster and less expensive design cycle, increased productivity, and increased revenue.