测井技术2017，Vol.41Issue(6)：732-737,6.DOI:10.16489/j.issn.1004-1338.2017.06.020
小直径中子孔隙度测井仪探头参数设计
Optimization Design on Detector Parameters for Small Diameter Neutron Porosity Logging Tool
摘要
Abstract
Under the condition of small borehole ,the responses of the measured parameters are different from the conventional logging measurements due to the small diameter of the logging instrument .In order to using the same calibration charts as conventional logging tools , the detector parameters of small diameter tool must be designed . The responses of the neutron porosity well logging tool with different diameters are studied with Monte Carlo numerical simulation method . And influence of the parameters such as shielding , instrument shell and source distance on the count ratio of small-diameter neutron logging instrument are also investigated .It can be obtained that the effect of shielding and shell on the neutron porosity logging is small ,and the source distance has a great influence on the thermal neutron counting rate and the ratio .By appropriately adjusting the source distance of the near and far detectors ,it is possible that the small-diameter logging tool has the same response as that of conventional neutron porosity instrument .And after adjustment ,they are almost suffered the same effect from borehole size ,lithology and other factors .As a result ,it realizes the compatible data processing for different types of neutron porosity logging instrument and provides technical support for the measurements of formation parameters under small borehole drilling conditions .关键词
测井仪器/中子孔隙度/小直径/优化设计/蒙特卡罗模拟Key words
logging tool/neutron porosity/small diameter/optimized design/Monte Carlo simu-lation分类
天文与地球科学引用本文复制引用
张锋,权奕君,吴赫..小直径中子孔隙度测井仪探头参数设计[J].测井技术,2017,41(6):732-737,6.基金项目
国家自然基金(41374125,41574119) （41374125,41574119）
国家重大油气专项(2017ZX05019005-005) （2017ZX05019005-005）
中央高校基本科研业务费专项资金资助(14CX05011A,15CX06008A) （14CX05011A,15CX06008A）
