Numerical Simulation of in-situ Cuttings Concentration Change due to Lost Circulation in Horizontal and Inclined Drilling

摘要

This paper describes the simulation model of in-situ cuttings concentration change due to lost circulation inhorizontal and inclined drilling. The mixture flow of cuttingsand mud fluid is regarded as the solid-liquid two-phase flow inthe annulus and the numerical simulation model is developedbased on the equation of motion of cuttings. The numericalsimulation of in-situ cuttings concentration change due to lostcirculation was carried out, and the simulated results werecompared with the previous research related to the cuttingsvelocity change due to lost circulation. As simulated resultsagreed with the experimental results in the previous research, itwas confirmed that the model developed here is reasonable.Therefore, by using this model, numerical simulation wascarried out again under several conditions. From the simulatedresults, it was found that the effect of lost circulation on thechange of in-situ cuttings concentration and height of movingbed becomes significant according to the decrease of theinclination angle of the drilling well.