Open AccessTO A QUESTION OF DETERMINATION OF HYDRAULIC RADIUS OF A BACKFILL FLOW FOR THE EXCENTRATIVE PLACEMENT OF PIPES IN DRILLING BORE
Author(s) -
V. M. Moishyshyn,
Y. S. Biletskii,
Viktor Vryukalo,
Mykola Seniushkovych
Publication year - 2018
Publication title -
prikarpatsʹkij vìsnik ntš. čislo
Language(s) - English
Resource type - Journals
ISSN - 2304-7399
DOI - 10.31471/2304-7399-2018-2(46)-197-209
Subject(s) - radius , dimensionless quantity , geotechnical engineering , mechanics , drilling , flow (mathematics) , geology , bend radius , geometry , engineering , structural engineering , physics , mathematics , mechanical engineering , computer security , computer science , bending
The processes of displacement of drilling clay backfill flow from the intertubular space formed by internal surface of external and external surfaces of inner tubes are considered. In case of eccentric placement of pipes it is proposed in the form of a cross-section of the flow of a backfill to take the area limited from the outside by the Pascal's snail, and from the inside - the outer surface of the inner pipe at the first time.
The formulas for determining areas of the cross section of the flow and the stagnant zone, the perimeter and the hydraulic radius of the section ofthe flow for the eccentric placement of the pipes in the bore are proposed. The dimensionless parameter α is introduced as the ratio of the centripetal distance to difference between internal radius of outer pipe and outer radius of inner tube. It was found that with increasing of α cross-sectional area and their hydraulic radii are increasing, and the area of stagnant zones decreases according to parabolic laws.It is established that with the growth of α velocity of the backfill flow decreases according to parabolic laws and their values are in good agreement with the experimental data.