SU1509543A1 - Method of determining air resistance of friction to gas-air stream of gas-rich mine working - Google Patents

Abstract

This invention relates to mine aerology and can be used in calculations of mine ventilation. The goal is to improve the accuracy of determining the magnitude of the aerodynamic resistance to friction of the gas-air flow (GWP) of the gas-rich generation (GWP) by taking into account the varying density and volume of GWP 13 due to its absorption and gassing. In a ventilated HV, a straight line segment with a required angle of inclination is chosen: a section of 2 GV of length 3, a section with a common or part of a section, a volume with a total of 6, or a part with 7 volumes. The gas concentration is measured at two points of the measurement section in GVP 13 and, if its values differ, the longitudinal 8 are distinguished along the measurement section and the transverse measurement points along the section. The elevations of the measurement points of the longitudinal 10, which are cross-sectional over the whole or part of the section of the HWP 13 with the initial speed of its movement, are measured. At the measurement points, the aerostatic pressure, t-ru, cross-sectional area, the length and volume of the measurement area, and the transit time of the PRT 13 between the measurement points are measured. Then, samples of the gas-air mixture are taken and its physico-chemical composition, additional volume and velocity of the HWP 13 are determined along the length of the measurement section. After that, the rate of HWP 13 is changed by increasing or decreasing its value relative to the initial value. Then, the measurements of the velocity of the HWP 13, the aerostatic pressure at the measuring points, t-ry and measure the length of the initial 14 and the final 15 parts of the measuring section are repeated. Subsequent operations are repeated for each selected area and the total aerodynamic resistance of the GWP 13 of the measurement area is determined by the derived mathematical expression with all measured parameters taken into account. 2 Il.

Description

13

SP

about with

00

(out of 1

the initial speed of its movement. At the measurement points, the aerostatic pressure, t-ru, cross-sectional area, length and volume of the measurement section and the time of the HWP 13 between ,.-. measurement points. Then samples of the gas-air mixture are taken and their physico-chemical composition, additional volume and velocity of the HWP 13 are determined along the length of the measurement section. After that, the rate of HWP 13 is changed by increasing or decreasing its value from 150

The invention relates to mine aerology and can be used in the calculations of the ventilation of mines by determining the aerodynamic resistance of friction ventilation flows as they move along gas-rich mine workings.

The purpose of the invention is to increase the accuracy of determining the magnitude of the aerodynamic resistance to friction of the gas-air flow of gas-producing mines by taking into account the varying density and volume of the gas flow due to its absorption and gas release,

Figure 1 shows the longitudinal section for measuring aerodynamic friction resistance; figure 2 - plot measurement, the cross section.

The method for determining the aerodynamic resistance to friction of a gas-rich exhaust is carried out as follows.

In the aerated gas-rich mine 1 (Figures 1 and 2), a straight-line section 2 of a length 3, section, total 4 OR part 5 of section, volume b or total volume 7 o. Is measured with the necessary angle of inclination, concentration is measured gas in the gas-air flow at two points of the measurement section and, if its values differ from the original th speed of it

9543 .4,

relative to the original. Then, the measurements of the velocity of the HHP 13, the aerostatic pressure at the measuring points of the vehicle are repeated, and the length of the initial 14 and the final 15 parts of the measuring section are measured. Subsequent operations are repeated for each selected area and the total aerodynamic resistance-GWP 13 of the measurement area is determined by the derived mathematical expression with all measured parameters taken into account. 2 Il.

five

0

0

0

5 movements, aerostatic pressure is measured at measurement points, temperature, cross-sectional area, length of measurement area, gas-air flow time between measurement points, volume of measurement area, gas-air mixture samples are taken, its physico-chemical composition is determined, molar: mass, specific gravity, static depression, density, mass of the gas-air mixture in the measured volume, additional volume of the gas-air mixture, speed of displacement of the flow along the length. plot metering. Then, the velocity of the gas-air flow is increased, increasing or decreasing its value relative to the initial velocity, the measurements of the flow velocity, the electrostatic pressure at the measuring points, the temperature are repeated, the initial 14 and 15 parts of the measuring section, their cross-section area are measured. , the time for the passage of the gas-air flow along the. the length of each part of the measurement area, their volumes, are taken,

In points, measuring gas sampling

the mixture, determine its physicochemical composition, molar mass, specific gravity, corrected, determine the indicator of flow mode, then choose along the length of generation 16. the necessary number of longitudinal 17, end 18 sections, measure distances from the beginning of development to the measurement points of the selected area, repeat the subsequent operations for each selected area and determine the total aerodynamic resistance to friction of the gas-air, the measuring flow of the measurement area from a mathematical expression

0

five

R

pi, n +,

LEadu ti 5j: f iU. | JDiU§uJjuu.J ilu ± -I iu; .. ii..J3i

 n-i r (n. ,, “t,

.LyajMl ““ “u“ JU-A - w “.“. B..A .... u..A..M ... di.

And (n-iin il i r (n-,), n pm.

n + 1

n

n-1, n + 1

- numbers of measurement points (, 2,3 ,, ..);

- averaging interval on the coordinate between p-1

I-1, L41

h-1, p-C

r (n-)

points 10

15

.20

,

p-1

and n + 1 measure;

aerodynamic resistance to gas-air friction,,

aerostatic pressure of the flow in the interval ri-1, n + 1 pu | 1ktov metering, Pa gas constant of the gas mixture in the initial p-1 metering point; J / (kg), determined by the formula

 %

pe-o-m:

universal gas constant, j / () | the molar mass of the gas-air mixture in the initial p-1 measurement point, kg / mol, is determined by the formula Kg- (

25

thirty

M

n-i

Mi (n.,), (N-)) 35

(pi1

.

1n-0

11-1

"-1, n + 1

molar mass of the 1st gas in the mixture at the starting point of measurement, kg / molJ

the share of i-ro gas in the mixture at the initial p-1 metering point; the number of gases in the mixture in the initial p-1 measurement point; the temperature of the gas mixture in the initial p-1 measurement point, K} is the section area in the interval n-1, n + 1 measurement points, m

2

the length of the section of production between p + 1 and p-1 measurement points, Mj

n + 1

0

five

0

five

h-i

h + 1

| Ph -.- .. l

r (n-0)

aerostatic pressure of the gas-air flow in the initial p-1. measurement point, Paj aerostatic pressure of the gas-air flow in the final n + 1 measurement point. Pa;

static depression of gas flow between n-1 and n + 1 metering points,. Para-gas-constant gas mixture in the interval n-1, n + 1 measurement points, j / (kg K), is determined 7 by the formula

„Ri

R

(, p.ts)

m

n-1, n +

M

- molar mass of gas-air mixture in the range of n-1, n + 1 measurement points,

kg / mol, is determined by the formula .n + i

eleven

ef,

l (n-,) + 4)

0

five

0

five

M,

i (n-l, "t- ()

c.

 "(.N-liHtl)

to

the molar mass of the i-th gas of the mixture in the range of n-1, n + 1 measuring points, kg / mol fraction of gas in the mixture in the range of n-1, n + 1 measuring points; the number of gases in the mixture in the range of p-1, n + 1 points of measurement, the temperature of the gas-air mixture in the range of n-1, n + G points. metering. TO; the volume of the gas-air mixture in the range of p-1, p + 1 measurement points at pressure P and temperature

p-11 p + 13

, m () y

uVi, - additional volume

r (n-i.n + il

gas-air mixture

(ntl

 hi, n.t-i

V.

 {n-lin + l

in the range of p-1, p + 1 measurement points from the change in the density of the gas-air mixture, m, is determined by the formula

bv..n. ,, r (n., nvn p br pir

nL, .- air-gas mass

r1p -) (1

flow mixture in the interval, n + 1 points

measurement, kg, defined by the formula

g ("h, VI + P" -.

 S

P-1,1Ts-H

(one

tH-1

.

P4-

) P + 1

- density of the gas-air i mixture in the range n-1, n + 1 measurement point, kg / m, is determined by the formula

n Sui jJil-en-jl + j. p-11 p + o t

   q -n-f, n + 1

about;

RP- (the density of the gas-gas mixture at the pg1 measuring point, kg / m-, is determined by, 30

20

25

RPM formula

Ml.,

 YET TGG

R T „.,

, iti) i

fiV, .- volume of gas-air

and

II, M +

mixtures of flow in the interval n-1, n + 1 measurement points, (plus - in the compression of the volume of flow, and minus - in its expansion) i - the rate of movement of the gas-air flow in the interval n-1, n + 1, measurement points, m / s, determined by the formula

n-t-1

- ln-1

- time of passage of the interval between the points n-1, n + 1 of measurement, cj

- is an indicator of the flow regime,

 (("- .." v,), for the movement of the flow is laminar, - turbulent, 2 - intermediate), is determined by the formula

ten

ta In (

R p - Rp-1

RP.G RP

Where

15

i

;

 , thirty

20

25

35

p p h-1 p

R

.P

P, M + (

, And p, p s

n - (. n, n,

the aerostatic pressure of the modified flow in p-1, p, n + 1 measurement points. Pa;

aerostatic pressure of the modified flow in p-1, d and p, n + 1 measurement intervals, Pa;

the volume of the gas-air mixture of the modified flow in the p-1, p and p, n + 1 measurement intervals, m,

the kinematic viscosity of the gas-air mixture of the modified flow in n-1, n and n, n + 1 measurement intervals,,.

0

five

0

five

p-1.and

n.nti production section, in

tn, -tfl), (.,) n-1, n and n, n + 1 measurement intervals, m,

rln-i, nV

(P, P4.)

ni, n

.AND,

pm

the transit time of the flow of the in-1 shaft between n + 1, n and n, n – 1 measurement points, s;

gas constant gas mixtures in n-1, pi n, n + 1 measurement intervals, j / (kg-K),

temperature of the gas-air mixture of the changed flow in the p-1, p and p, n + 1 measurement intervals. TO;

dynamic viscosity of gas-air mixture

example

modified flow in p-1, p and p, n + 1 measurement intervals. Pa-s. The values of Pn are measured., 101325; P „., 101225; Pn -., R, 4f 101275-, 5. ,, „,, 5,2-,„ ,, - 1, 100; T „., 238; Т „, 292, Т„., „, 290, samples of the gas-air mixture were collected and Mm 28,68 10 was determined

gz

M

.128,640-, M

n-ii

28.64-10

- 3

RU. 8.314, the density of the gas-air flow was determined to be p 1.2136j Pn | P4-1 1.2030 determined the mass and volume of the gas-air mixture flow ™ r (h - ,, nH) 625.04; AV, („. ,,„,)

 five; r (h-., 520; measured "n 16.66; Un-, | tt + i. 6. Measured with changing speed

P „., 101210; Р „101386; U „.,.„ 52 M „.,„ 28,610 -),., „15,046-10-, S, and, n 5,2, t ,, t 8-.84-, М„, п, 28, 6-10-, T „.,,„ ,, 287, fU ,,,, 18.02 7.86; M

10- Зп - ,, and 5.1,

i-, n

 28.6 10

-3

 P

-n-i

Ti-1,4. 288, rl „. ,,, 18.03.10- U ,,„ n 520

p., 15.032-10.Distinct HP indicator of the mode of motion: gas-air mixture

: then 2;

 determined by the general aerodynamic

friction resistance

2

n - (, n-2 ;; g

78 ----- ha

The application of the proposed method allows to achieve improved ventilation of workings and the creation of more safe working conditions for the miners.

Claims (1)

Invention Formula The method for determining the aerodynamic resistance to friction of the gas-air flow of a gas-rich mine working, including the selection of a straight-line measurement section, measurement of its length, 25 45 m I t Si; JAll. LtauiS; LU - i.Ul ,. Z ijl: J 2 .. n-, r (n-i, n + 0 (hM, n + t) - bVr (f,. ,, n4,)) and. ,, „4. TP, „, n numbers of measurement points. (2,3 ...), p-1, n + 1 - coordinate averaging interval between n-1 0 five 0 the cross-sectional area, the initial speed of movement over the measurement section of the gas-air flow, static depression, characterized in that in order to increase the accuracy of determining the aerodynamic resistance to friction of the gas-air flow of the gas-rich production by taking into account the varying density and volume of the gas-air flow due to its absorption and gas release, gas concentration in the gas-air flow at two points of the measurement site and, if its values differ, mark the measurement points, measure the longitudinal and transverse the hundredth marks of the measurement points, as well as the aerostatic pressure, temperature, time of the gas-air flow between the measurement points, the volume of output between the measurement points, are taken at the measurement points of the sample of the gas-air mixture, their physicochemical composition is determined, the molar mass, the specific weight, density, mass of gas-air flow between points of measurement, additional volume of gas-air mixture, speed of movement of flow between points. measuring, then changing the speed of movement of the gas-air flow, increasing or decreasing its value relative to the initial speed, repeating measurements of the speed of movement of the flow, aerostatic pressure at measuring points, temperature, measuring the length of the initial and final parts of the measuring section, their cross-sectional area, the time of passage of the gas-air flow along the length of each part of the measurement section, their volumes, are taken at the measurement points of the sample of the gas-air mixture, its physico-chemical composition, molar mass, specific gravity, viscosity are determined The flow rate indicator is calculated and the aerodynamic magnitude is calculated: the friction resistance of the gas-air flow of the gas-rich mine workout section from the mathematical expression m I 0 five 0 five t i.Ul ,. Z ijl: J 2 .. pi, and + and n + 1 measurement points; aerodynamic resistance to gas-air friction friction, Pa-s / m; aerostatic pressure of flow in the range of p-1, n + 1 points of measurement. Pa; gas constant gases in the initial p-1 point and in the interval. n-1, n + 1 measurement points, respectively,, Cf / (kg K) J the temperature of the gas mixture in the initial p-1 point and in the range of p-1, n + 1 measurement points, respectively, K-, the area of the section of the site in the interval n-1, n + 1 measuring points, m 2,  h-i-1 -j,., is the length of the production area . melod n + 1 and p-1 point-; mi, m; / X Editor A, Zaitseva Compiled by S. Erokhin Tehred M. Khodanych Order 5780/29 Circulation 410 BSHSS of the State Committee for Inventions and Discoveries at the FKHT USSR 113035, Moscow, Zh-35, Raushsk nab 4/5 Production Publishing House Ii Combine Patent, Uzhgorod, ul. Gagarin, 101 Prt-i n + i rtn-i. the static depression of the gas-flow is less than n-1 and n + 1 metering points. Pa; the volume of gas-air mixture in the range of p-1, p + 1 measurement points, m; ; 0 g (and - (, and + 1) additional volume of gas-air mixture in the interval n-1, n + 1 measurement points, m, -. Velocity of the gas-air flow in the interval n-1, n + 1 measurement points , m / cm - indicator of the flow regime in the interval 0 points of measurement p-1, p + 1, in the case of a laminar movement mode, - turbulent, - intermediate. Proofreader L. Beskid Subscription