Двигатели внутреннего сгорания. 2010. №2 PDF (Size:7770 МБ)

Рабочие процессы ДВСplot the histogram it is necessary to divide the frequencyof each interval into its length and use the acquiredvalue as the height of the rectangle.In case of equal by length intervals the heights ofthe rectangles are proportional to corresponding frequencies.It comes out of the histogram plotting that itstotal are equals one.In this example of the assumed statistical data thelength of intervals are not equal because the prototypedistribution has a very sharp increase of the distributiondensity in the area from 4 to 12 μm (see fig. 1,curve 1). Therefore the intervals from # 1 up to # 8 arenarrower than from # 9 up to # 16.In the table 2 it is given data for plotting the histogram.The histogram constructed accordingly to the datagiven in the table 2 is shown on fig. 3.0On the fig. 3: x – d k , Nkp– I i , f(x) – a smoothingcurve,4Nkp– the frequency,2Nkp– the number ofdroplets.In principle plotting the statistical function of thedistribution already solves the problem of a descriptionof the experimental material preliminary illustrated onfig. 1, 2. However plotting the function of distributionwith the aid of the equation 1 is not so convenient – inthe sense of imagination ability. Often it is better to useother characteristics of statistical distributions, analogousnot to the function of a distribution but the densityof the distribution. This method uses the equation(2).f( x)〈〉 4N kp0.070.06510 − 4 〈〉 2⋅N kp00.0530.0350.01800 10 20 30 40 500〈〉 0xN , kp45Fig. 3. Distribution, histogram, and smoothing curveTable 2Data for plotting the histogram## I i m i*p i1 0-1 0 0 0 02 1-2 3 3 0,000595 0,0005953 2-3 28 28 0,005553 0,0055534 3-4 230 115 0,045617 0,0228085 4-5 115 0 0,0228086 5-6 492 246 0,09758 0,048797 6-7 246 0 0,048798 7-8 630 315 0,12495 0,0624759 8-9 315 0 0,06247510 9-10 321 321 0,063665 0,06366511 10-11 312 312 0,06188 0,0618812 11-12 828 276 0,164221 0,0547413 12-13 276 0 0,0547414 13-14 276 0 0,0547415 14-15 633 211 0,125545 0,04184816 15-16 211 0 0,04184817 16-17 211 0 0,04184818 17-18 480 160 0,0952 0,03173319 18-19 160 0 0,03173320 19-20 160 0 0,03173321 20-21 540 108 0,1071 0,0214222 21-22 108 0 0,0214223 22-23 108 0 0,0214224 23-24 108 0 0,0214225 24-25 108 0 0,0214226 25-26 270 54 0,05355 0,0107127 26-27 54 0 0,0107128 27-28 54 0 0,0107129 28-29 54 0 0,0107130 29-30 54 0 0,0107131 30-31 150 30 0,02975 0,0059532 31-32 30 0 0,0059533 32-33 30 0 0,0059534 33-34 30 0 0,0059535 34-35 30 0 0,0059536 35-36 80 16 0,015867 0,00317337 36-37 16 0 0,00317338 37-38 16 0 0,00317339 38-39 16 0 0,00317340 39-40 16 0 0,00317341 40-41 45 9 0,008925 0,00178542 41-42 9 0 0,00178543 42-43 9 0 0,00178544 43-44 9 0 0,00178545 44-45 9 0 0,001785Σ 0-45 504250421 1ДВИГАТЕЛИ ВНУТРЕННЕГО СГОРАНИЯ 2'2010 37