An investigation of engineering properties of groundnut pods and kernels related to design the post-harvest machines

The aim of this investigation is to study the main physical, mechanical and aerodynamic properties of groundnut pods and kernels (Giza 5 variety) at moisture content (8.2% db). Some engineering properties, such as size, weight, percentages of the pod parts, repose angle, coefficient of friction, rapture force, deformation distance, projected mean area, and terminal velocity were measured. The 3-Dimensional linear characteristics of the samples obtained from linear measurement led to the conclusion that groundnut (Giza 5 variety) is oblong shape. The average length, width, thickness, geometric mean diameter, sphericity, surface area and aspect ratio of groundnut contains one kernel were 25.15 mm, 18.03 mm, 16.01 mm, 19.28 mm, 77.62 %, 1176.2 mm² ,73.16 % and hull thickness was 1.53 mm, respectively. For groundnut contains two kernels these characteristics were 38.62 mm, 16.17 mm, 14.91 mm, 21.23 mm, 55.38 %, 1423 mm² ,43.82 % and hull thickness was 1.46 mm, respectively. While the groundnut contains three kernels were 45.63 mm, 15.71 mm, 14.57 mm, 21.84 mm, 48.05 %, 1502 mm² ,34.64 % and hull thickness was 1.25 mm, respectively. On the other hands, the kernels characteristics were 20.29 mm, 10.24 mm, 9.42 mm, 12.51 mm, 61.64 %, 491.13 mm² and 50.47 %, respectively. The mean values of the weight percentages of pod parts to whole pod were 68.7 and 31.3 %, for kernels and hulls respectively. The average of repose angle and coefficient of friction of the groundnut pods and kernels were found to be 31.5°, 25.75°, and 0.36, 0.47, respectively. The rapture force of groundnut pods contain two kernels was higher than rapture force of groundnut pods contain three kernels and one kernel at horizontal position, it was 73.82 N. While the rapture force of groundnut pods contain one kernel was higher than rapture force of groundnut pods contain two kernels and three kernels at vertical position, it was 264.87 N. The deformation distance of groundnut pods contain one kernels was less than deformation distance of groundnut pods contain two kernels and three kernels at horizontal position, it was 2.4 mm. While the deformation distance of groundnut pods at vertical position increased when the kernels increased in pods. The mean values of terminal velocity were found 7.8, 8.1 and 7.9 m/s, respectively for pods which contain (one, two and three kernels). While the mean values of terminal velocity both kernel and hull were 7.52 and 4.06 m/s. Finally, the projected area of groundnut pods contain three kernels was higher than projected area of groundnut pods contain three kernels and one kernel it was 6.54 m/s. while, the mean value of projected area for kernels 1.76 m/s.