Xiaoyong Gu^*, Guohe Jiang, Yang Wo, Biwen Chen

Frontiers in Heat and Mass Transfer, Vol.15, No.1, pp. 1-8, 2020, DOI:10.5098/hmt.15.3

Abstract The heat transfer characteristics of propylene glycol-water (PG-W) mixture with different concentrations in shell side of spiral wound heat exchanger (SWHE) with different geometric parameters were studied numerically. Experiment was carried out and the average difference between the simulated results and the experimental results was 5.3%. The simulation results show that heat transfer coefficient increases with the increase of center core diameter and longitudinal spacing of tubes, but decreases with the increase of tube outer diameter. The center core diameter and tube outer diameter have greater effects on heat transfer performances at higher concentration. Economic index was established and found… More >

Jian Yao, Fayi Yan^*, Xuejian Pei

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.6, pp. 1425-1445, 2023, DOI:10.32604/fdmp.2023.025282

Abstract Proton exchange membrane fuel cells (PEMFCs) are largely used in various applications because of their pollution-free products and high energy conversion efficiency. In order to improve the related design, in the present work a new spiral flow field with a bypass is proposed. The reaction gas enters the flow field in the central path and diffuses in two directions through the flow channel and the bypass. The bypasses are arranged incrementally. The number of bypasses and the cross-section size of the bypasses are varied parametrically while a single-cell model of the PEMFC is used. The influence of the concentration of… More > Graphic Abstract

Fadhil Mukhlif^1,*, Ashraf Osman Ibrahim², Norafida Ithnin¹, Roobaea Alroobaea³, Majed Alsafyani³

CMC-Computers, Materials & Continua, Vol.74, No.3, pp. 5589-5606, 2023, DOI:10.32604/cmc.2023.034323

Abstract Due to the fact that network space is becoming more limited, the implementation of ultra-dense networks (UDNs) has the potential to enhance not only network coverage but also network throughput. Unmanned Aerial Vehicle (UAV) communications have recently garnered a lot of attention due to the fact that they are extremely versatile and may be applied to a wide variety of contexts and purposes. A cognitive UAV is proposed as a solution for the Internet of Things ground terminal’s wireless nodes in this article. In the IoT system, the UAV is utilised not only to determine how the resources should be… More >

Yukun Lv¹, Fan Yang^1,*, Zi’an Wei¹, Quan Lu²

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.2, pp. 379-397, 2023, DOI:10.32604/fdmp.2022.020373

Abstract Leakage occurring in the tube sockets of the main steam thermometers can seriously threaten the safe operation of coal-fired power plants. Here, assuming a 300 MW unit as a relevant testbed, this problem is investigated numerically through solution of the equations of fluid-dynamics in synergy with the mathematical treatment of relevant statistics. The results indicate that the steam can form a large-scale spiral flow inside the tube socket and continuously scour the inner wall. In the model with the protective casing setting angle of 60°, the average tangential fluid velocity can reach up to 4.8 m/s, which is about twice higher… More > Graphic Abstract

Andi Tang, Huan Zhou^*, Tong Han, Lei Xie

CMES-Computer Modeling in Engineering & Sciences, Vol.130, No.1, pp. 331-364, 2022, DOI:10.32604/cmes.2021.017310

Abstract The sparrow search algorithm (SSA) is a newly proposed meta-heuristic optimization algorithm based on the sparrow foraging principle. Similar to other meta-heuristic algorithms, SSA has problems such as slow convergence speed and difficulty in jumping out of the local optimum. In order to overcome these shortcomings, a chaotic sparrow search algorithm based on logarithmic spiral strategy and adaptive step strategy (CLSSA) is proposed in this paper. Firstly, in order to balance the exploration and exploitation ability of the algorithm, chaotic mapping is introduced to adjust the main parameters of SSA. Secondly, in order to improve the diversity of the population… More >

Yongtao Yu, Guangdong Zou^*

Oncologie, Vol.23, No.2, pp. 293-301, 2021, DOI:10.32604/Oncologie.2021.015520

Abstract Objective: The purpose was to explore the value of multi-slice spiral CT (MSCT) multiplanar reconstruction technique in the diagnosis and clinicopathological analysis of gastrointestinal lymphoma (GIL). Methods: 82 GIL patients treated in our hospital from February 2018 to February 2019 were selected as the experimental group of this study, and 82 patients with other gastrointestinal tumors diagnosed by pathology during the same period were selected as the control group. Both groups of patients were scanned by MSCT and analyzed by multiplanar reconstruction technique to compare the diagnostic results and clinicopathological indexes of the two groups. Results: The diagnostic accuracy of… More >

Anju Pradeep¹, S. Mridula¹, P. Mohanan²

CMC-Computers, Materials & Continua, Vol.52, No.3, pp. 187-196, 2016, DOI:10.3970/cmc.2016.052.185

Abstract A highly compact chipless tag based on Frequency coding technique using Spiral Resonators is proposed in this paper. Spirals are well known metamaterial structures and thus capable of sharp resonance, and hence Spiral Resonators can serve as a good candidate for RF Identity Tags. The bit capacity of the proposed tag is 10 bits per sqcm. The prototype of the tag is fabricated on a low-cost substrate of dielectric constant 4.4 and loss tangent 0.02. The overall dimension of tag is 15.4 x 3 x 1.6 mm³. Two methods for reading the tags are also discussed in this paper. Scope… More >

S. Gao¹, K. Nakasa², K. Nogi³, L. Huang⁴

CMC-Computers, Materials & Continua, Vol.22, No.1, pp. 39-54, 2011, DOI:10.3970/cmc.2011.022.039

Abstract An incremental press-forming method was newly developed for the fabrication of spiral plates of a continuous screw conveyer, boring screw, screw pump and so on. In this method, a pair of V-shaped punches and dies with two opposite inclined edges are used instead of punch and die with spiral surfaces. The experiments on incremental forming were carried out on aluminum alloy and steel disks with a hole and a slit, and the deformation process of the plate during and after the press-forming was simulated by a finite element method (FEM). The press-forming shows that the spiral plate has a correct… More >