Different drillingfluid systems are designed according to mineral composition,lithology and wellbore stability of different strata.In the present study,the conversion of a non-dispersed polymer drillingfluid into a low ...Different drillingfluid systems are designed according to mineral composition,lithology and wellbore stability of different strata.In the present study,the conversion of a non-dispersed polymer drillingfluid into a low potas-sium anti-collapsing drillingfluid is investigated.Since the two drillingfluids belong to completely different types,the key to this conversion is represented by new inhibitors,dispersants and water-loss agents by which a non-dispersed drillingfluid can be turned into a dispersed drillingfluid while ensuring wellbore stability and reason-able rheology(carrying sand—inhibiting cuttings dispersion).In particular,the(QYZ-1)inhibitors and(FSJSS-2)dispersants are used.The former can inhibit the hydration expansion capacity of clay,reduce the dynamic shear force and weaken the viscosity;the latter can improve the sealing effect and reduce thefiltrate loss.The results have shown that after adding a reasonable proportion of these substances(QYZ-1:FSJSS-2)to the non-dispersed polymer drillingfluid,while the apparent viscosity,plastic viscosity,structural viscosity andfluidity index under-went almost negligible changes,the dynamic plastic ratio increased,and thefiltration loss decreased significantly,thereby indicating good compatibility.According to the tests(conducted in the Leijia area),the density was 1.293 g/cm3,and after standing for 24 h,the SF(static settlement factor)was 0.51.Moreover,thefiltration loss was reduced to 4.0 mL,the rolling recovery rate reached 96.92%,with excellent plugging and anti-collapse performances.展开更多
As the supporting supplier of the main engine plant, the general air filter manufacturers have insufficient technical reserves. The structural optimization of air filter is often based on the bench experiment, which h...As the supporting supplier of the main engine plant, the general air filter manufacturers have insufficient technical reserves. The structural optimization of air filter is often based on the bench experiment, which has high implementation cost and poor performance. In view of this, taking computational fluid dynamics(CFD) as the basic technical means, an optimization design method based on parametric sensitivity combined with equidistant search was proposed. Specifically, the sensitivity of local structure parameters to pressure loss was analyzed by taking local structure of air filter as the object. According to the sensitivity, the method of equidistant search was used to optimize the parameters in order, so as to achieve the goal of overall optimization. After optimization, the pressure loss decreased by 45.13% and the effect was remarkable.展开更多
文摘Different drillingfluid systems are designed according to mineral composition,lithology and wellbore stability of different strata.In the present study,the conversion of a non-dispersed polymer drillingfluid into a low potas-sium anti-collapsing drillingfluid is investigated.Since the two drillingfluids belong to completely different types,the key to this conversion is represented by new inhibitors,dispersants and water-loss agents by which a non-dispersed drillingfluid can be turned into a dispersed drillingfluid while ensuring wellbore stability and reason-able rheology(carrying sand—inhibiting cuttings dispersion).In particular,the(QYZ-1)inhibitors and(FSJSS-2)dispersants are used.The former can inhibit the hydration expansion capacity of clay,reduce the dynamic shear force and weaken the viscosity;the latter can improve the sealing effect and reduce thefiltrate loss.The results have shown that after adding a reasonable proportion of these substances(QYZ-1:FSJSS-2)to the non-dispersed polymer drillingfluid,while the apparent viscosity,plastic viscosity,structural viscosity andfluidity index under-went almost negligible changes,the dynamic plastic ratio increased,and thefiltration loss decreased significantly,thereby indicating good compatibility.According to the tests(conducted in the Leijia area),the density was 1.293 g/cm3,and after standing for 24 h,the SF(static settlement factor)was 0.51.Moreover,thefiltration loss was reduced to 4.0 mL,the rolling recovery rate reached 96.92%,with excellent plugging and anti-collapse performances.
基金Supported by the General Plan Projects of Science and Technology of Jiangxi Provincial Department of Education(GJJ151161,GJJ180976)the Plan Projects of Science and Technology of Jiangxi Provincial Department of Science and Technology(20161BBE50053)the Foundation of the Center of Collaboration and Innovation(18XTKFYB03)
文摘As the supporting supplier of the main engine plant, the general air filter manufacturers have insufficient technical reserves. The structural optimization of air filter is often based on the bench experiment, which has high implementation cost and poor performance. In view of this, taking computational fluid dynamics(CFD) as the basic technical means, an optimization design method based on parametric sensitivity combined with equidistant search was proposed. Specifically, the sensitivity of local structure parameters to pressure loss was analyzed by taking local structure of air filter as the object. According to the sensitivity, the method of equidistant search was used to optimize the parameters in order, so as to achieve the goal of overall optimization. After optimization, the pressure loss decreased by 45.13% and the effect was remarkable.
