Guowei Zhu^*, Kangliang Guo, Haoran Yang, Xinchen Gao, Shuangshuang Zhang

FDMP-Fluid Dynamics & Materials Processing, Vol., , DOI:10.32604/fdmp.2022.020942

Abstract In order to overcome the typical limitations of numerical simulation methods used to estimate the production of low-permeability reservoirs, in this study, a new data-driven approach is proposed for the case of water-driven hypo-permeable reservoirs. In particular, given the bottlenecks of traditional recurrent neural networks in handling time series data, a neural network with long and short-term memory is used for such a purpose. This method can reduce the time required to solve a large number of partial differential equations. As such, it can therefore significantly improve the efficiency in predicting the needed production performances. Practical examples about water-driven hypotonic… More >

Xi Zhang¹, Changquan Wang^1,*, Hua Wu², Xu Zhao²

FDMP-Fluid Dynamics & Materials Processing, Vol., , pp. 1-17, DOI:10.32604/fdmp.2022.019486

Abstract The oil production predicted by means of the conventional water-drive characteristic curve is typically affected by large deviations with respect to the actual value when the so-called high water-cut stage is entered. In order to solve this problem, a new characteristic relationship between the relative permeability ratio and the average water saturation is proposed. By comparing the outcomes of different matching methods, it is verified that it can well reflect the variation characteristics of the relative permeability ratio curve. Combining the new formula with a reservoir engineering method, two new formulas are derived for the water flooding characteristic curve in… More >

Jinliang Zhu¹, Xiulei Wang¹, Guihua Wang¹, Xianglin Zhong², Zhenguo Li³, Zhiming Wang¹, Ke Sun^1,*, Shuzhan Bai^1,*

FDMP-Fluid Dynamics & Materials Processing, Vol., , pp. 1-11, DOI: 10.32604/fdmp.2022.019311

Abstract Exhaust thermal management is essential to allow engines to meet the Euro VI emissions standards and reducing nitrogen oxide emissions is one of the most important targets being pursued nowadays. Along these lines, in the present study, engine’s thermal performances have been evaluated on the basis of a WHTC test, namely a transient engine dynamometer schedule defined by the global technical regulation (GTR) developed by the UN ECE GRPE group (the GTR is covering a world-wide harmonized heavy-duty certification (WHDC) procedure for engine exhaust emissions). The influence of thermal management on fuel consumption, intake, and tailpipe NO_x have been quantitatively… More >

Yu Tang¹, Jingcun Yu¹, Benyu Su^1,3,*, Zhixiong Li²

FDMP-Fluid Dynamics & Materials Processing, Vol., , pp. 1-10, DOI:10.32604/fdmp.2022.019609

Abstract The complex resistivity of coal and related rocks contains abundant physical property information, which can be indirectly used to study the lithology and microstructure of these materials. These aspects are closely related to the fluids inside the considered coal rocks, such as gas, water and coalbed methane. In the present analysis, considering different lithological structures, and using the Cole-Cole model, a forward simulation method is used to study different physical parameters such as the zero-frequency resistivity, the polarizability, the relaxation time, and the frequency correlation coefficient. Moreover, using a least square technique, a complex resistivity “inversion” algorithm is written. The… More >