Experimental analysis for optimization of separation of grain and MOG at separator with elliptical trajectories and a big axis in vertical direction

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Harold Lawrence
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1 Faculty of Mechanical Engineering Chair Agricultural Systems and Technology Experimental analysis for optimization of separation of grain and MOG at separator with elliptical trajectories and a big axis in vertical direction Experimentelle Untersuchung zur Optimierung der Korn-Stroh- Trennung am Hordenschüttler unter Verwendung elliptischer Bahnkurven mit einer großen Achse in vertikaler Richtung Jörg Bernhardt, Thomas Herlitzius, Robert Bühlmeier, Hubert Korte VDI-MEG Kolloquium Mähdrescher, Hohenheim, 12./13. September 213

2 Content 1. Definition of project 2. Theoretical assessment 3. Test stand and configuration 4. Test versions 5. Test results 6. Prospect 7. Summary Slide 2

3 Definition of project better effective performance straw quality power requirement conventional hybrid performance of combines with tangential separation and straw walker is smaller than performance of combines with rotary separation straw walker is performance limiting function unit Slide 3

4 Definition of project separation depends on parameters of grain MOG mixture! machine parameter design parameter - radius, speed of crank shaft - length, width of separator - operating parameters - total / MOG performance - optional auxiliary equipment walker aid (active driven) - multi finger separation system, intensive separation system (Claas) - power separator (John Deere) - parameter of grain / MOG mixture - conveying velocity - material density - material height - transfer of impact force into grain MOG mixture material parameter - ratio of grain and MOG - straw length - grain / MOG moisture - green material inside straw - material type excitation of grain MOG mixture circular path vs. alternative trajectories? Slide 4

5 Definition of project influencing of grain separation: optimization of design and operating parameters walker aid for reducing compactness of grain MOG mixture analyzed in literature further increase of performance is not expected Slide 5

6 Definition of project influencing of grain separation: optimization of design and operating parameters walker aid for reducing compactness of grain MOG mixture analyzed in literature further increase of performance is not expected changing of excitation of grain MOG mixture by separator just few information in literature further increase of performance is expected intention of analysis determination of parameters of grain straw mixture that result from different trajectories and determination of their influence on grain separation Slide 6

7 Theoretical assessment crank shaft radius r K [m] Radius r [m],5,45,4,35,3,25,2,15,1,5 Einfachwurf K=1 K=3,3 Wechselwurf John Deere Agco Drehzahl n[min -1 ] crank shaft speed n [rpm] = r K New Holland Fortschritt Claas g 2 requirement for optimal grain separation: combination of crank shaft radius and speed is located in area of Einfachwurf Slide 7

8 Theoretical assessment max. Max. acceleration Beschleunigung b bmax [m/s²] v F evaluation: n v r F = 6 r K =1mm K r K =3mm r K =5mm,2,4,6,8 1 conveying Fördergeschwindigkeit velocity v F [m/s] r K =7mm speed range: n= rpm influence of conveying speed at constant acceleration or influence of acceleration at constant conveying speed by changing of crankshaft radius possible BUT! high effort Slide 8

9 Theoretical assessment conveying velocity acceleration grain- MOG- mixture (constant material parameter) parameter machine parameters known, constant separation process separator Material parameters unknown, non-constant grain- MOG- mixture density material height MOG + grain loss separated grain principal characteristic known actual characteristic depends on machine (known) and material parameters (unknown) tests are necessary Slide 9

10 Theoretical assessment possible combinations by max > bx max by max = bx max by max < bx max v F > v F-KB v F = v F-KB v F < v F-KB legend v F v F- bx max by max conveying velocity conveying velocity of circular path max. acceleration at x- direction max. acceleration at y- direction realized by circular path assumption: grain separation can be increased by increasing separating force start lab tests with trajectories with a big axis in vertical direction (red marked combination) objective: improvement in performance of 1 % with 1 % grain loss compared to circular path Slide 1

11 Test stand and configuration feeding equipment header + feeder house threshing unit curtain straw walker area of visual inspection trajectory linkage y x separation classes constant parameters value conveyor belt speed of feeding equipment speed of intake auger conveying speed at feeder house speed of driving shaft of feeder house speed of threshing drum diameter of threshing drum 2,8 m/s 24 rpm 3,1 m/s 425 rpm 75 rpm 6 mm concave clearances 14mm; 1mm; 7mm Slide 11

Test stand and configuration 1 2 1 connection of straw walker 2 3 3 2 3 link extender wheel 4 4 4 driving shaft 5 5

12 Test stand and configuration connection of straw walker link extender wheel driving shaft 5 5 transition frame trajectory linkage 5 main frame γ ϕ=const. 1 6 setting range of γ { 2 } shaft centre distance: 7mm +ϕ 5 5 Slide 12

13 Test stand and configuration measured variable - total mass - grain mass - grain loss - conveying speed - material height measurement equipment - electronic scale - digital camera h = 1 3 BA 3 BA h i i= 1 with BA = 6 n f R h i grain / MOGmixture ρ = m& ges h v F B straw walker Slide 13

14 Test versions path V big axis [mm] small axis [mm] pitch [ ] speed range [rpm] max. acceleration x-direction y-direction [m/s²] [m/s²] 18,5...31,4 26,5...44,7 23,5...32,8 31, ,9...28,6 25, ,9...29,2 36,1...5,4 22,9...31,1 47,7...64,9 V circular path Slide 14

15 Test results - speed test - standardized Norm. Kornverlust grain loss [%]_ [%] 5 4,5 4 3,5 3 2,5 2 1,5 1,5 24 rpm,4,45,5,55,6,65,7 Fördergeschwindigkeit conveying velocity [m/s] [m/s] V Slide 15

16 Test results - speed test - standardized Norm. Kornverlust grain loss [%]_ [%] 5 4,5 4 3,5 3 2,5 2 1,5 1,5 22 rpm 24 rpm 26 rpm,4,45,5,55,6,65,7 Fördergeschwindigkeit conveying velocity [m/s] [m/s] V y- coordinate [m] x- coordinate [m] Slide 16

17 Test results - speed test - standardized Norm. Kornverlust grain loss [%]_ [%] 5 4,5 4 3,5 3 2,5 2 1,5 1,5 22 rpm 24 rpm 26 rpm,4,45,5,55,6,65,7 Fördergeschwindigkeit conveying velocity [m/s] [m/s] V y- coordinate [m] x- coordinate [m] Slide 17

18 Test results - speed test - standardized Norm. Kornverlust grain loss [%]_ [%] 5 4,5 4 3,5 3 2,5 2 1,5 1,5 2 rpm 22 rpm 24 rpm,4,45,5,55,6,65,7 Fördergeschwindigkeit conveying velocity [m/s] [m/s] V y- coordinate [m] x- coordinate [m] Slide 18

19 Test results - speed test - standardized Norm. Kornverlust grain loss [%]_ [%] 5 4,5 4 3,5 3 2,5 2 1,5 1,5 22 rpm 26 rpm 25 rpm 24 rpm,4,45,5,55,6,65,7 Fördergeschwindigkeit conveying velocity [m/s] [m/s] V y- coordinate [m] x- coordinate [m] Slide 19

20 Test results - speed test - standardized Norm. Kornverlust grain loss [%]_ [%] 5 4,5 4 3,5 3 2,5 2 1,5 1,5 24 rpm 26 rpm 28 rpm,4,45,5,55,6,65,7 Fördergeschwindigkeit conveying velocity [m/s] [m/s] V y- coordinate [m] x- coordinate [m] target MOG throughput of 25 t/h standardization of 25t/h necessary because of fluctuating of ratio between grain and MOG range of optimal conveying velocity between,5 and,6 m/s grain loss of and is lower than grain loss of circular path Slide 2

21 Test results - comparison of parameters - Comparison of parameters of grain MOG deposit at conveying velocity of,6 m/s grain loss [%] 3,5 3 2,5 2 1,5 1,5 density [kg/m³] material thickness [mm] density of and is slightly higher than density of circular path similar material thickness of all tested trajectories Slide 21

22 Test results - comparison of parameters - Comparison of parameters of grain MOG deposit at conveying velocity of,6 m/s by max bx max number of impulse [/] max. acceleration in x- direction [m/s²] max. acceleration in y- direction [m/s²] tendency visible that grain loss becomes smaller with: smaller number of impulse smaller acceleration in x- and y- direction Slide 22

23 Test results - comparison of parameters - Comparison of parameters of grain MOG deposit at conveying velocity of,6 m/s distance of adjacent straw walkers x x- direction [m],1,8,6,4,2, y product of distance in x- and y- direction of adjacent straw walkers correlate with grain loss y- direction [m],14,12,1,8,6,4,2, product of distance in x- and y- direction grain loss becomes smaller with larger product of distance in x- and y- direction x*y [m²],8,6,4,2 Slide 23

24 grain loss [%] ,2 grain separation of is better than grain separation of circular path for different MOG throughput Test results - MOG throughput loss characteristic - 23, MOG throughput [t/h] Weg in x-richtung [m] x- coordinate [m] increase of MOG throughput of 4,4 % for 1% grain loss (repeatable) Weg y- coordinate y-richtung [m] [m] BUT! Increased performance limited because the effect of material parameters at separation could not be tested sufficiently in lab. Slide 24

25 Prospect machine parameter size of trajectory + pitch of trajectory effect of speed effect of optional auxiliary equipment / walker aid effect of terrain (longitudinal-, lateral inclination) - length, width, pitch - drop step - offset of straw walkers analyzed grain loss analysis required material parameter ratio of grain and MOG length of straw moisture of grain and MOG amount of green material kind of material analysis not required a lot of parameters need to be analyzed in field tests field tests not useful for trajectory a significant performance improvement is necessary (minimum 1%) Slide 25

26 Summary 5 different trajectories were tested in lab achieved performance improvement is less than 5% compared to circular path further studies are necessary to achieve required performance improvement of 1% planned tests: tests with big axis in horizontal direction simplification of drive kinematic is necessary to integrate the drive into the machine and to reduce costs grain separation is influenced by: interaction of all parameters of grain MOG mixture bulking of grain MOG mixture by relative movement of adjacent straw walkers elliptical trajectories have a speed where grain loss is minimal Slide 26

27 Summary increasing number of impulses has no advantage reduction of number of impulses is advantageous to improve the migration of the kernels separation force in x- and y- direction is needed for separation process lab tests show a tendency that lower accelerations in y- direction are favorable for grain separation at a constant density Slide 27

28 Thank you for your attention! Vielen Dank für Ihre Aufmerksamkeit! Slide 28

The influence of position of the first straw walker s section on grain separation

Agronomy Research 6(Special issue), 377 385, 8 The influence of position of the first straw walker s section on grain separation D. Steponavičius, L. Špokas and S. Petkevičius Department of Agricultural