Jianlu Cheng¹, Kaiyong Hu^1,*, Jiang Shen¹, Lu Jia^1,2, Rui Niu¹, Zhaoxian Yang³

FDMP-Fluid Dynamics & Materials Processing, Vol.18, No.4, pp. 1049-1066, 2022, DOI:10.32604/fdmp.2022.019007 - 06 April 2022

Abstract The use of ammonia in large-scale refrigeration systems (such as those used for a stadium) requires adequate ammonia leakage prevention mechanisms are put in place. In the present study, numerical simulations have been conducted to study the dispersion law in the ammonia machinery room of the refrigeration system for the 2022 Beijing Winter Olympics. The wind speed, and release location have been varied to investigate their effects on the dispersion profile. Different positions of the leakage points in the ammonia storage tank have been found to lead to different areas affected accordingly. In general, the More >

Aimin Zhang, Mingzhi Lu^*

FDMP-Fluid Dynamics & Materials Processing, Vol.18, No.4, pp. 907-918, 2022, DOI:10.32604/fdmp.2022.018995 - 06 April 2022

Abstract In this study, it is shown how recycled rubber and waste plastics can modify the softening point and penetration of asphalt traditionally used for highways. It is shown that the modified asphalt can meet the performance index requirements when the components are present with a certain proportion or relative ratio (1:3.5). The dispersion process of the masterbatch in base asphalt can effectively be implemented, with good results and a smaller mixing time. The proposed approach may be regarded as a good strategy to achieve energy savings and protection of the environment. More >

Yuzhuo Wang^1,2, Zhichao Xu^2,*

FDMP-Fluid Dynamics & Materials Processing, Vol.18, No.4, pp. 897-906, 2022, DOI:10.32604/fdmp.2022.018972 - 06 April 2022

Abstract Polyurethane is enjoying a widespread use as a polymer-based waterproof material in civil engineering In the present study we consider a temperature-sensitive waterproof and moisture-permeable polyurethane material (PTPE-PU) characterized by one or more phase transition temperatures (critical temperatures). Near the critical temperature, the waterproof and moisture permeability of polyurethane undergo abrupt changes. The related stability, thermal performance, water resistance, hydrostatic pressure, and moisture permeability are investigated here considering a PTPE-PU traditionally used in bridge geotechnical engineering. The results show that the moisture permeability of the coated bridge rock and soil undergo sudden variations near the More >

M. Gh. Mohammed Kamil^1,*, M. S. Kassim¹, R. A. Mahmood^2,3, L. AZ Mahdi⁴

FDMP-Fluid Dynamics & Materials Processing, Vol.18, No.4, pp. 985-998, 2022, DOI:10.32604/fdmp.2022.018938 - 06 April 2022

Abstract This work investigates the steam condensation phenomena in an air-cooled condenser. The considered horizontal flattened tube has a 30 mm hydraulic diameter, and its length is a function of the steam quality with a limit value between 0.95 and 0.05. The mass flow rate ranges from 4 to 40 kg/m².s with a saturated temperature spanning an interval from 40°C to 80°C. A special approach has been implemented using the Engineering Equation Solver (EES) to solve a series of equations for the two-phase flow pattern and the related heat transfer coefficients. A wavy-stratified structure of the two-phase flow More >

Wen Sun, Hao Liu, Ming Han, Ke Sun, Shuzhan Bai^*, Guoxiang Li^*

FDMP-Fluid Dynamics & Materials Processing, Vol.18, No.4, pp. 867-882, 2022, DOI:10.32604/fdmp.2022.018923 - 06 April 2022

Abstract Fuel cell hybrid electric vehicles are currently being considered as ideal means to solve the energy crisis and global warming in today’s society. In this context, this paper proposes a method to solve the problem related to the dependence of the so-called optimal equivalent factor (determined in the framework of the equivalent consumption minimum strategy-ECMS) on the working conditions. The simulation results show that under typical conditions (some representative cities being considered), the proposed strategy can maintain the power balance; for different initial battery’s states of charge (SOC), after the SOC stabilizes, the fuel consumption More >

Tianyu Xu¹, Yanru Su¹, Zhouming Su¹, Shuteng Zhi¹, Ennan Zheng^1,*, Chengcheng Yan²

FDMP-Fluid Dynamics & Materials Processing, Vol.18, No.4, pp. 1169-1182, 2022, DOI:10.32604/fdmp.2022.018628 - 06 April 2022

Abstract The bionic structure drip irrigation emitter (BSDE) is a new-type emitter, by which better hydraulic performances can be obtained. In the present work, twenty-five sets of orthogonal test schemes were implemented to analyze the influence of the geometric parameters of the flow channel on the hydraulic characteristics and energy dissipation efficiency of this emitter. Through numerical simulations and verification tests, the flow index and energy dissipation coefficient were obtained. According to the results, the flow index of the BSDE is 0.4757–0.5067. The energy dissipation coefficient under the pressure head of 5–15 m is 584–1701. The More >

Shihong Huang¹, Ting Lei², Yan Cui³, Zhifeng Nie^4,*

FDMP-Fluid Dynamics & Materials Processing, Vol.18, No.4, pp. 883-896, 2022, DOI:10.32604/fdmp.2022.018537 - 06 April 2022

Abstract The distribution of titanium, carbon and associated elements (calcium, magnesium, silicon and aluminum) in a smelting process is studied by means of a chemical equilibrium calculation method for multiphase and multicomponent systems, and verified through comparison with production results. In particular, using the coexistence theory for titanium slag structures, the influence of the AIR (anthracite to ilmenite ratio) on the distribution of such elements is analyzed. The results show that the AIR can be adjusted to achieve a selective reduction of oxides in the melt. More >

Fugang Dong, Yuqiao Zheng^*, Hao Li, Zhengwen He

Energy Engineering, Vol.119, No.3, pp. 1017-1029, 2022, DOI:10.32604/ee.2022.020430 - 31 March 2022

Abstract This work takes the bionic bamboo tower (BBT) of 2 MW wind turbine as the target, and the non-dominated sorting genetic algorithm (NSGA-II) is utilized to optimize its structural parameters. Specifically, the objective functions are deformation and mass. Based on the correlation analysis, the target optimization parameters were determined. Furthermore, the Kriging model of the BBT was established through the Latin Hypercube Sampling Design (LHSD). Finally, the BBT structure is optimized with multiple objectives under the constraints of strength, natural frequency, and size. The comparison shows that the optimized BBT has an advantage in the More >

Haibin Cao¹, Houqi Dong¹, Yongjie Ren¹, Yuqing Wang^2,*, Na Li³, Ming Zeng¹

Energy Engineering, Vol.119, No.3, pp. 965-984, 2022, DOI:10.32604/ee.2022.020051 - 31 March 2022

Abstract As the proportion of renewable energy power generation continues to increase, the number of grid-connected microgrids is gradually increasing, and geographically adjacent microgrids can be interconnected to form a Micro-Grid Community (MGC). In order to reduce the operation and maintenance costs of a single micro grid and reduce the adverse effects caused by unnecessary energy interaction between the micro grid and the main grid while improving the overall economic benefits of the micro grid community, this paper proposes a bi-level energy management model with the optimization goal of maximizing the social welfare of the micro… More >

Zong Bi^*, Weifeng Shi, Tiewei Song

Energy Engineering, Vol.119, No.3, pp. 907-928, 2022, DOI:10.32604/ee.2022.019627 - 31 March 2022

Abstract In the marine electric power system, the marine generators will be disturbed by the large change of loads or the fault of the power system. The marine generators usually installed power system stabilizers to damp power system oscillations through the excitation control. This paper proposes a novel method to obtain optimal parameter values for Power System Stabilizer (PSS) to suppress low-frequency oscillations in the marine electric power system. In this paper, a newly developed immune clone selection algorithm was improved from the three aspects of the adaptive incentive degree, vaccination, and adaptive mutation strategies. Firstly,… More >