A b s t r a c t. The objective of this study was the evaluation of the aerodynamic properties of Makhobeli, triticale and wheat seeds as a function of moisture content from 7 to 27% (w.b). The results showed that the terminal velocity of triticale and wheat seeds increased linearly from 5.37 to 6.42 and from 6.31 to 8.02 m s -1 , respectively, as the moisture content increased from 7 to 27%. Over this same moisture content range, the terminal velocity of Makhobeli seeds varied following a polynomial relationship from 4.52 to 5.07 m s -1 . Makhobeli seeds had terminal velocities with a mean value of 4.73 m s -1 , at different moisture contents, compared to the mean values of 5.89 and 7.13 m s -1 for triticale and wheat seeds, respectively. The mean value of drag coefficient was 1.12 for Makhobeli compared to the values of 0.92 and 0.85 for triticale and wheat, respectively. The analysis of variance showed that there were significant differences between the terminal velocity (at 1% probability level) and drag coefficient (at 5% probability level) of Makhobeli with triticale and wheat seeds, which suggests that aerodynamic separation of Makhobeli from triticale and wheat is possible.K e y w o r d s: separation, post harvest operation, Makhobeli, weed control, triticale, wheat

Mechanical damage of seeds due to harvest, handling and other process is an important factor that affects the quality and quantity of seeds. Seed damage result in lower grain value, storability problem, and reduced seed germination and seedling vigor and subsequent yield of crops. The objective of this research was to determine the effects of moisture content and impact energy on the breakage susceptibility of wheat and triticale seeds. The experiments were conducted at five moisture contents of 7.5, 12, 17, 22 and 27% w.b. and at the impact energies of 0.05 and 0.1 J. The percentage of breakage of both wheat and triticale seeds increased as impact energy increased. The analysis of variance showed that there was a significant difference between breakage susceptibility of wheat and triticale seeds at the 1% probability level. Triticale seeds had more breakage than wheat seeds. For both wheat and triticale seeds as the moisture content of the seeds increased, the amount of the percentage breakage of seeds decreased as a polynomial. The average values of percentage breakage of wheat seeds decreased from 43.81 to 19.88% as the moisture content increased from 7.5 to 27%. Over this same moisture content range the percentage breakage of triticale seeds varied from 81.34 to 37.77%. Below the moisture contents of 17% for the wheat and 22% for the triticale the percentage breakage of seeds increased dramatically.

A b s t r a c t. Aerodynamic properties of solid materials have long been used to convey and separate seeds and grains during post-harvest operations. The objective of this study was evaluation of the aerodynamic properties of green and red lentil seeds as a function of moisture content from 10 to 25% (w.b.). The results showed that as the moisture content increased from 10 to 25%, the terminal velocity of seeds increased, following a linear relationship, from 6.90 to 9.14 and from 6.37 to 7.67 m s -1 for green and red lentil seeds, respectively. Seeds of the green variety had terminal velocities with a mean value of 7.89 m s -1 , while the red variety had a mean value of 7.02 m s -1 , for moisture content from 10 to 25%. The Reynolds number increased linearly from 2 310.90 to 3 269.23 and from 1 215.02 to 1 535.09 for green and red lentil seeds, respectively, with the increase of seeds moisture content from 10 to 25%. While, drag coefficient decreased from 0.69 to 0.40 and from 0.84 to 0.69 for green and red lentil seeds, respectively, with the increase of moisture content. Mathematical relationships were developed to relate the change in seeds moisture content with the values of aerodynamic properties obtained. The analysis of variance showed that the effect of moisture content on all aerodynamic properties of lentil beans was significant at the 1% probability level.

In this research, the breakage susceptibility of two classes of lentil (green and red) was evaluated as affected by impact energy and seed moisture content. The experiments were conducted at impact energies of 0.1, 0.2 and 0.3 J, and moisture contents of 10, 12.5, 15, 17.5, 20 and 25% (wet basis). Results showed that red lentil seeds had more breakage than green seeds and the difference in breakage percentage between green and red lentil seeds was significant at 0.01% level according to analysis of variance (p < .01). Percentage breakage of both green and red lentil seeds increased as the energy of impact increased. With increasing the seed moisture content of the both green and red lentils, the breakage percentage of seeds decreased. The average values of seeds breakage green and red lentil seeds varied from 100 to 67.7% and from 100 to 93.1%, respectively, as the seeds moisture content increased from 10 to 25%. The optimum seed moisture at which minimum damage was observed was 17.5% for green lentil and 15% for red lentil. Mathematical relationships composed of lentil seeds moisture content and energy of impact were developed for accurate description of the breakage percentage of green and red lentil seeds under impact loading.

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