Faculty of Mechanical Engineering Chair Agricultural ...app.claas.com/2013/university-symposia/download/... · Experimental analysis for optimization of separation of grain and MOG

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 2013

Faculty of Mechanical Engineering Chair Agricultural Systems and Technology

September 13, 2013 Slide 2VDI-MEG Kolloquium Mähdrescher

Content

1. Definition of project

2. Theoretical assessment

3. Test stand and configuration

4. Test versions

5. Test results

6. Prospect

7. Summary


Definition of project

� 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

effective performance

power requirement

straw quality

bette

r

conventional hybrid


parameter of grain / MOG mixture- conveying velocity- material densitymaterial height- transfer of impact force into grain MOG mixture

� separation depends on parameters of grain MOG mixture!


machine parameterdesign 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)- …

excitation of grain MOG mixturecircular path vs.alternative trajectories

material parameter- ratio of grain and MOG- straw length- grain / MOG moisture- green material inside straw- material type

?



analyzed in literature�further increase of

performance is not expected

influencing of grain separation:

� walker aid for reducing compactness of grain MOG mixture

� optimization of design and operating parameters



just few information in literature

�further increase of performance is expected

analyzed in literature�further increase of

performance is not expected

influencing of grain separation:

� walker aid for reducing compactness of grain MOG mixture

� changing of excitation of grain MOG mixture by separator

� optimization of design and operating parameters

intention of analysis

�� determination of parameters of grain straw mixture that result from different trajectories and determination of their influence on grain separation


Theoretical assessment

0

0,05

0,1

0,15

0,2

0,25

0,3

0,35

0,4

0,45

0,5

80 100 120 140 160 180 200 220 240 260 280 300

Drehzahl n[min-1]

Rad

ius

r [m

] K=3,3

K=1

John Deere

FortschrittClaas

Wechselwurf

Einfach-wurf

New Holland

crank shaft speed n [rpm]

Agco

cran

k sh

aft r

adiu

s r K

[m]

� requirement for optimal grain separation:

� combination of crank shaft radius and speed is located in area of “Einfachwurf”

gr 2K ⋅

=



� influence of conveying speed at constant acceleration or influence of acceleration at constant conveying speed by changing of crankshaft radius

possible

� BUT! high effort

0

10

20

30

40

50

60

70

0 0,2 0,4 0,6 0,8 1

Fördergeschwindigkeit vF [m/s]

Max

. B

esch

leun

igun

g b m

ax [

m/s

²] vF evaluation:

KF r60

nv ⋅⋅=

max

. acc

eler

atio

n b m

ax[m

/s²]

rK=10mm

rK=30mm

rK=70mm

speed range:n=140...260 rpm

conveying velocity [m/s]

rK=50mm


separator

machine parametersknown, constant

Material parametersunknown, non-constant

grain- MOG- mixture(constant material parameter)

MOG + grain loss

separated grain

parameter

grain- MOG- mixture

densitymaterial height

conveying velocityacceleration

separation process

� principal characteristic known

� actual characteristic depends on machine (known) and material parameters

(unknown)

� tests are necessary



possible combinations

bymax > bxmax bymax = bxmax bymax < bxmax

vF > vF-KB vF = vF-KB vF < vF-KB

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 10 % with 1 % grain loss compared to

circular path

max. acceleration at x- directionmax. acceleration at y- direction

bxmax…bymax…

conveying velocity of circular pathvF-KrB…

conveying velocityvF…legend



Test stand and configuration

area of visual inspection

header+

feeder house

threshing unit

curtain

straw walker

separation classes

1

750 rpm600 mm

speed of threshing drumdiameter of threshing drum

14mm; 10mm; 7mmconcave clearances

3,1 m/s425 rpm

conveying speed at feeder housespeed of driving shaft of feeder house

204 rpmspeed of intake auger

2,8 m/sconveyor belt speed of feeding equipment

valueconstant parameters

x

feeding equipment

trajectory linkage

2 3 4 5 6 7 8 9 10y


connection of straw walker

extender wheel

link

� setting range of γ {0°…20°}

� shaft centre distance: 700mm


1

2

2

3

3

5

6

1

2

3

4

4

4 driving shaft

5 transition frame

5 main frametrajectory linkage

+ϕ

γ 1

5 5

ϕ=const.


hi

grain / MOG-mixture

straw walker

Rfn60

BA ⋅=∑⋅

=⋅

⋅=

BA3

1iih

BA31

h

BFvhgesm

ρ⋅⋅

=&

- digital camera- conveying speed- material height

- grain loss

- electronic scale- grain mass

- total mass

measurement equipmentmeasured variable


with


Test versions

47,7...64,922,9...31,1240…2807547149EB-V36,1...50,420,9...29,2220…2607567137EB-IV25,7...3719,9...28,6200…24080EB-III31,5...4423,5...32,8220…26075EB-II26,5...44,718,5...31,4220…26085

85120EB-I

max. acceleration x-direction y-direction[m/s²] [m/s²]

speed range[rpm]

pitch [°]

smallaxis[mm]

bigaxis[mm]

path

circular path

EB-I EB-II EB-III EB-IV EB-V


00,5

11,5

22,5

33,5

44,5

5

0,4 0,45 0,5 0,55 0,6 0,65 0,7Fördergeschwindigkeit [m/s]

Nor

m. K

ornv

erlu

st [%

]_ KrB

EB-I

EB-II

EB-III

EB-IV

EB-V

Test results - speed test -

240 rpm


stan

dar

diz

ed g

rain

loss

[%

]

KrB


00,5

11,5

22,5

33,5

44,5

5


Nor

m. K

ornv

erlu

st [%

]_ KrB

EB-I

EB-II

EB-III

EB-IV

EB-V

Test results- speed test -

240 rpm

220 rpm

260 rpm

stan

dar

diz

ed g

rain

loss

[%

]


KrB

y-co

ordi

nate

[m]

x- coordinate [m]

-0.08 -0.04 0 0.04 0.08-0.08

-0.04

0

0.04

0.08

Weg in x Richtung [m]

EB-I


00,5

11,5

22,5

33,5

44,5

5


Nor

m. K

ornv

erlu

st [%

]_ KrB

EB-I

EB-II

EB-III

EB-IV

EB-V

240 rpm220 rpm260 rpm


stan

dar

diz

ed g

rain

loss

[%

]


KrB

x- coordinate [m]

y-co

ordi

nate

[m]

y-co

ordi

nate

[m]

x- coordinate [m]

y-co

ordi

nate

[m]

x- coordinate [m]

-0.08 -0.04 0 0.04 0.08-0.08

-0.04

0

0.04

0.08

EB-II


00,5

11,5

22,5

33,5

44,5

5


Nor

m. K

ornv

erlu

st [%

]_ KrB

EB-I

EB-II

EB-III

EB-IV

EB-V220 rpm

200 rpm240 rpm


stan

dar

diz

ed g

rain

loss

[%

]


KrB

y-co

ordi

nate

[m]

x- coordinate [m]

-0.08 -0.04 0 0.04 0.08-0.08

-0.04

0

0.04

0.08

EB-III


00,5

11,5

22,5

33,5

44,5

5


Nor

m. K

ornv

erlu

st [%

]_ KrB

EB-I

EB-II

EB-III

EB-IV

EB-V

240 rpm

220 rpm260 rpm

250 rpm


stan

dar

diz

ed g

rain

loss

[%

]


KrB

y-co

ordi

nate

[m]

x- coordinate [m]

-0.08 -0.04 0 0.04 0.08-0.08

-0.04

0

0.04

0.08

EB-IV


00,5

11,5

22,5

33,5

44,5

5


Nor

m. K

ornv

erlu

st [%

]_ KrB

EB-I

EB-II

EB-III

EB-IV

EB-V

� 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 0,5 and 0,6 m/s

� grain loss of EB-II and EB-III is lower than grain loss of circular path

260 rpm

240 rpm

280 rpm


stan

dar

diz

ed g

rain

loss

[%

]


KrB

y-co

ordi

nate

[m]

x- coordinate [m]

-0.08 -0.04 0 0.04 0.08-0.08

-0.04

0

0.04

0.08

EB-V


Test results- comparison of parameters -

� density of EB-II and EB-III is slightly higher than density of circular path

� similar material thickness of all tested trajectories

Comparison of parameters of grain MOG deposit at conveying velocity of 0,6 m/sgr

ain

loss

[%]

dens

ity [k

g/m

³]

mat

eria

l th

ickn

ess

[mm

]

0

0,51

1,5

2

2,53

3,5

EB-V KrB

EB-IEB-IIEB-II

I

02468

1012141618

EB-V KrB

EB-IEB-IIEB-II

I0

100

200

300

400

500

EB-V KrB

EB-IEB-IIEB-II

I



Comparison of parameters of grain MOG deposit at conveying velocity of 0,6 m/s

� tendency visible that grain loss becomes smaller with:

� smaller number of impulse

� smaller acceleration in x- and y- direction

num

ber

of

impu

lse

[/]

max

. acc

eler

atio

n in

x-

dire

ctio

n [m

/s²]

max

. acc

eler

atio

n in

y-

dire

ctio

n [m

/s²]

0

50

100

150

200

250

EB-V KrB

EB-IEB-IIEB-II

I

05

10152025303540

EB-V KrB

EB-IEB-IIEB-II

I

01020304050607080

EB-V KrB

EB-IEB-IIEB-II

I

bxmax

bymax



Comparison of parameters of grain MOG deposit at conveying velocity of 0,6 m/s

� product of distance in x- and y- direction of adjacent straw walkers correlate with

grain loss

� grain loss becomes smaller with larger product of distance in x- and y- direction

x-di

rect

ion

[m]

distance of adjacent straw walkers

y-di

rect

ion

[m]

x*y

[m²]

product of distance in x-and y- direction

0,00

0,02

0,04

0,06

0,08

0,10

EB-V KrB

EB-IEB-IIEB-II

I

0,000,02

0,040,060,080,10

0,120,14

EB-V KrBEB-IEB-IIEB-II

I0

0,002

0,004

0,006

0,008EB-V KrB

EB-IEB-IIEB-II

I

x

y


� grain separation of EB-II is better than grain separation of circular path for different

MOG throughput

� increase of MOG throughput of 4,4 % for 1% grain loss (repeatable)

� BUT! Increased performance limited because the effect of material parameters at

separation could not be tested sufficiently in lab.

Test results- MOG throughput loss characteristic -

22,2

23,2

-0.08 -0.04 0 0.04 0.08-0.08

-0.04

0

0.04

0.08

Weg in x-Richtung [m]

Weg

in y

-Ric

htun

g [m

]

MOG throughput [t/h]

gra

in lo

ss [

%]

x- coordinate [m]

y-co

ordi

nate

[m]

0

1

2

3

4

5

6

7

18 20 22 24 26 28 30NKB-Durchsatz [t/h]

KrB-240EB-II-220


Prospect

material parametermachine parameter

grain loss

size of trajectory + pitch of trajectory

effect of optional auxiliary equipment / walker aid

- length, width, pitch- drop step- offset of straw walkers

effect of terrain(longitudinal-, lateral inclination)

ratio of grain and MOG

length of straw

moisture of grain and MOG

amount of green material

kind of material

effect of speed

analysis requiredanalyzed analysis not required

� a lot of parameters need to be analyzed in field tests

� field tests not useful for trajectory EB-II � a significant performance improvement is necessary

(minimum 10%)


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 10%

� 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


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


Vielen Dank für Ihre Aufmerksamkeit!

Thank you foryour attention !

Documents

Faculty of Mechanical Engineering Chair Agricultural ...app.claas.com/2013/university-symposia/download/... · Experimental analysis for optimization of separation of grain and MOG