Nurushev S , Ph.D.

Koctanai state University. A.Baitursynov

Optimization parameters tillage combined machine

Annotation

To justify the rational parameters and modes of operation for the combined processing machines solonetsz soils used the method of proactive planning of the experiment. The resulting mathematical relationship to determine the nature and extent of the influence of various parameters ( factors ) on the process .

Rational parameters combined machine to ensure quality processing of topsoil at the lowest cost of energy.

Surface treatment of virgin Solonetz - land subject to a radical improvement , and other grassed under hayfields and pasture soils currently operate heavy disc harrows for three to five passages or meadow bog cutters for one. Milling effective than disking , but more energy intensive . Recently studied combined ripping - rotary working bodies . [1] Preliminary studies of KGU and VIM found that they allow comparison with milling to reduce the energy intensity of the process of surface treatment virgin solonetsz soils in 1.4 ... 1.8 times the load on the tractor PTO at 1.9 ... 2.8 times [ 2] . Constructive- technological scheme of working bodies includes staggered flat cutter paws placed them active rotor with a horizontal axis of rotation and support- packer rштл .

The objective of this study - substantiation of rational parameters and operating modes combined machine for solonetsz soils .

Given the complexity of the process , which involves many interrelated factors to reduce the time and amount of research to improve their standard applied a proactive planning of the experiment. The resulting mathematical relationship to determine the nature and extent of the influence of various parameters ( factors ) on the process .

For the mathematical description of the object used in the study area plan Hartley. His choice due to the fact that the latter when n = 4 is the minimum number of experiments compared to the plan of the central composite planning and their own statistical properties similar to D - optimal [3]. The plan allows you to describe the process of a mathematical model of the second order in the form of :

,

Where - the constant term ;

, , , - The regression coefficients ;

.

Priori analysis and the results of preliminary experiments showed that for quality and energy performance of the combined machine the most significant effect of the number of active workers , the distance between the disks , speed milling drum and speed unit ( Table 1).

Table 1 - Levels and intervals varying factors

Level of factor	Factors
	Number of knives x1	Distance between disks х2, m	Shaft speed of milling reel х3, min^-1	Speed of movement х4, m/s
Main	3	0,150	280	1,94
Upper (+1)	4	0,165	380	2,78
Lower (-1)	2	0,135	180	1,11
Interval of variation	1	0,015	100	0,83

As the degree of optimization criteria adopted crumbling surface layer , the content of particles and erosion-prone energy intensity of tillage . Due to the fact that after the main reclamation treatment prior to planting, the soil is exposed to steam treatment effects of autumn and spring rainfall , according to recommendations [4] for the exponent crumbling above solonetsz horizon adopted 70 % and the minimum particle erosion-prone .

Degree of crumbling soil erosion and maintenance of hazardous particles was determined using sieves by the standard method according to OST 70.4.2-80 .

Specific energy tillage сombine machine was determined by the following relation [5] :

,

where M - torque of the cutting drum , identified by a strain gauge shaft and oscillographic equipment kN ∙ m;

- The angular velocity of the milling reel, s-1 ;

Р_Т - tractive resistance combined machine defined using devices , m;

h - depth treatment , m;

- Translational speed of the unit, m / s .

Investigations were carried out on cultivated medium loamy solonetzes occupied by perennial grasses , with firmness in the soil layer 0 ... 3.8 MPa 0.20 m and 14.9% moisture using a laboratory- field installation allows you to change the design parameters and operating modes . The average depth of 0.15 m equal treatment implementation multifactorial experiment with 17 experiments in the main series triplicate is shown in Table . 2 . To eliminate systematic errors of the order of the experiments was on a table of random numbers.

Table 2 - Planning Matrix and the results of experiments to determine the quality and energy performance of the combined milling machine.

The procedure for conducting experiments	Level factors				Crumbling, %		Contents erosion dangerous particles, %		Specific energy, кVt/dm^3
	х1	х2	х3	х4
9	-1	-1	-0,94	+0,8	53,90	53,07	7,28	11,03	89,7	85,15
1	+1	-1	-0,93	+0,77	57,90	61,03	31,78	31,91	127,37	132,08
17	-1	+1	-0,95	-1,07	62,29	62,55	16,08	15,53	99,8	96,81
5	+1	+1	-0,93	-0,93	73,94	72,11	40,11	36,75	99,73	96,89
4	-1	-1	+0,95	-0,97	88,96	89,35	22,31	22,32	141,43	137,16
2	+1	-1	+0,93	-0,93	93,01	96,44	43,37	40,46	179,2	182,23
16	-1	+1	+0,81	+0,83	76,38	76,34	33,06	34,25	159,07	154,46
8	+1	+1	+0,85	+0,9	85,03	81,80	40,27	41,35	119,0	115,37
3	-1	0	-0,01	+0,07	81,74	83,20	20,50	21,24	125,9	128,92
15	+1	0	-0,04	+0,03	90,50	90,27	36,81	36,87	216,1	219,93
6	0	-1	+0,03	+0,17	87,05	84,63	33,76	32,84	112,47	108,66
13	0	+1	+0,05	+0,13	91,60	87,29	23,72	21,69	108,9	112,37
11	0	0	-0,94	+0,13	74,25	73,08	13,54	14,03	91,8	93,9
12	0	0	+0,80	+0,03	87,60	86,61	30,01	28,12	146,0	145,61
14	0	0	-0,07	-0,97	89,56	87,25	18,07	17,00	127,13	128,28
7	0	0	-0,07	+0,73	73,41	76,19	17,16	18,04	94,6	91,36
10	0	0	+0,01	+0,03	81,38	87,14	21,30	22,24	123,77	129,52

Processing of experimental data , the calculation of the regression coefficients , assess their significance , check the reproducibility of the process and the adequacy of equations conducted by a known method using a computer " Nairi -4 " [6] .

Checking equally accurate measurements carried out by Cochran , It affirms at a significance level of 0.05 . Coefficient of regression equation calculated by formulas for the plan Hartley type 2k- 1 were evaluated for statistical significance by Student t-test . After exclusion of irrelevant and clarify significant coefficients were obtained by the following regression equation :

on the degree of crumbling soil , %

;

on the degree of erosion-prone content particles ( sputtering )

;

on specific energy , Dzh/dm3

.

Check on the adequacy of the equations obtained by Fischer shows that the condition of adequacy is performed and the resulting regression equation with a significance level of 5% to adequately describe the process.

To justify the rational parameters used graphic-analytical method for finding the conditional extremum [6]. Finding the optimal area was conducted by a combination of two-dimensional sections of the response surface ( specific energy , power crumbling and dangerous content erosion particles) and find a compromise solution. Analysis of two-dimensional sections of the response surface led to the conclusion that the minimum criteria for energy consumption , maintenance erosion-prone soil particles and the extent of 70% of crumbling rational values of the factors are:

Operating speed 2.5 ... 2.8 m / s;

milling reel speed 215 ... 275 min-1 ;

disc spacing 0.13 ... 0.14 m ;

Number of knives per disc 3 ... 4 pcs.

Conclusions

1. Application Hartley plan to support parameters of a combined machine with proper choice of intervals and varying levels of factors provides a solution to the problem .

2 . Rational parameters combined machine to ensure quality processing of topsoil at the lowest cost of energy.

References

1. Zhuk A Finding type parameters and rationale for the combined working of seedbed : Author. dis. Candidate . tehn. Sciences . - M. , 1978 .

2. Marchenko O, Bychkov V, Zhulamanov K, S Nurushev Results of the study of combined working bodies for the surface treatment of virgin solonetsz soils / / scientific-technical. Bull. Agricultural Sciences , VIM . - 1986 . - Issue . 63.

3. Katsev P Statistical methods for investigating the cutting tool. - M.: Engineering , 1974.

4. USSR State Agricultural Committee recommendations on the use of new techniques for the development of solonetsz soils . - M. , 1987.

5. Yatsuk E Rotary and other tillage machines . - engineering , 1971 .

6. Melnikov S Design of experiments and other studies in agricultural processes . - Leningrad: Kolos , 1980 .