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1

Shear properties of a honeycomb structure with zero Poisson’s ratio

Song L., Sun Y., Han Z., Wang T., Wang H., Yin C., Shen X.

Archives of Mechanics

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2023

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Vol. 75, nr 5

521--541

EN

Honeycomb structures with zero Poisson’s ratio show promising potential for application in variable-sweep wing aircraft. The shear properties of these honeycomb structures serve as a crucial indicator of their morphing capacity. This paper derives the linear and non-linear shear properties of a honeycomb structure with zero Poisson’s ratio. A modified factor is introduced to establish a relationship between the linear and non-linear shear modulus of the honeycomb structure, simplifying the calculation method of the non-linear shear modulus. The validity of theoretical predictions is then confirmed using the finite element method Furthermore, the influences of the geometric parameters on the shear properties of the honeycomb structure with zero Poisson’s ratio are investigated, highlighting the varying contributions of these cell geometric parameters to the shear properties.

2

Hydrodynamic load and parametric design of grouted clamp used on offshore jacket

Zhang B, Wang Z., Wang T.

Polish Maritime Research

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2018

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S 3

154--165

EN

The reliability and safety of offshore platform are an important research aspect in marine engineering. The jacket platform is mainly used for oil development and submarine drilling, and the long-term work in the marine environment will be subjected to different loads, which will lead to the damage of the structure part of the offshore platform. It affects the structural strength of the platform. For the repair of jacket damage, grouted reinforcement technology is adopted, which has the advantages of simple underwater installation and low cost. The reinforcement technology of the grout hoop has been applied to the engineering projects abroad, but the stress and serialization design of the hoop in the marine environment need further study. This paper will combine the ocean current and wave force to carry out the research of underwater work and prevent loosening, and put forward the parametric design method for the specific size of the hoop. Two types of experimental models are designed: short bolt form clamp and long bolt form clamp. The mechanical experiment of the long bolt clamp is carried out, and the relationship between the slipping force and the bolt preload is analyzed, so as to verify the theoretical analysis.

3

Reciprocity relations for light wave scattered by a particulate collection

Jiang Z., Zhu Z., Wang T.

Optica Applicata

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2018

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Vol. 48, nr 4

661--670

EN

Two Fourier relations of light waves scattered by a random-distributed particulate medium have been investigated. We find that the scattered field and the particulate collection satisfy two Fourier relations, i.e. the spectral density is directly proportional to a Fourier transform of a convolution of correlation coefficient of each particle and correlation coefficient of distribution function of the whole collection, and the spectral degree of coherence is directly proportional to a Fourier transform of a convolution of strength of the scattering potential of each particle and strength of the distribution function of the whole collection. To illustrate these relations, behaviors of the far-field generated by Gaussian-correlated particles with Gaussian-correlated distributions have been discussed.

4

Experimental verification of the steering performance of all-hydraulic crawler chassis

Lv X., Shi X., Lv X., Wang T.

Engineering Transactions

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2018

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Vol. 66, iss. 4

427--442

EN

The force conditions in the steering system of the chassis under different conditions are analyzed theoretically for the independently designed and developed all-hydraulic crawler chassis. Using the multi-body dynamic simulation software RecurDyn, the chassis steering performance on sandy loam and clay pavements, and the steering performance under different steering radiuses on the sandy loam pavement are simulated and analysed dynamically respectively. The steering resistance moment is studied when the pavement conditions and steering radius are different. This research selects inside and outside crawler slip ratio as an index, and road conditions, speed and steering radius as factors to test the steering performance of all-hydraulic crawler chassis under different operating conditions. It is observed from the simulation results that during the pivot steering on the sandy loam, the drive torque and braking torque of the driving wheel are larger than on the clay ground. With the decrease of the steering radius, the torques of the left and right driving wheel are both gradually increasing. In the same steering radius, the torque of the outside driving wheel is larger than that of the inside driving wheel. The simulation results are consistent with the theoretical analysis results. In the steering performance test, the factors influencing the slippage rate on both sides of the crawler are such that the influence of the steering radius is greater than that pf the pavement condition and the pavement condition influence is greater than that of the speed. Among them, the steering radius has a significant influence on the slip ratio of the inside crawler, and an extremely significant influence on the slip ratio of the outside crawler. This research can provide a certain theoretical basis and technical reference for the development of hydraulic crawler chassis and optimization of the steering system.

5

Research on tool wear based on multi-scale simulation in high speed cutting Inconel 718

Fan Y. H., Wang T., Hao Z. P., Lan H., Cui R. R.

Archives of Civil and Mechanical Engineering

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2018

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Vol. 18, no. 3

928--940

EN

Nickel-based superalloy Inconel718 has excellent properties such as good fatigue resistance, creep resistance, oxidation resistance and corrosion resistance. It has been widely used in aerospace industry. However, nickel-based superalloy is a kind of typical difficult-to process-material. The alloying elements which enhanced material exist in the form of high hardness compound (TiC, NbC and other interphase hard point). These high hardness compounds led to complicate cutting deformation, high cutting temperature, large cutting force and severe tool wear. According to the characteristics in cutting Inconel718 and the microstructure of cemented carbide tool, the wear properties and mechanism of carbide tool in cutting Inconel718 process are revealed by multi-scale analysis method. The main wear forms that wear debris peeled from the tool substrate are given and the evolution mechanism of tool wear caused by the crack in the cutting process is deeply studied.

6

Curvelet-domain multiple matching method combined with cubic B-spline function

Wang T., Wang D., Tian M., Hu B., Liu C.

Acta Geophysica

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2018

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Vol. 66, no. 4

559--573

EN

Since the large amount of surface-related multiple existed in the marine data would influence the results of data processing and interpretation seriously, many researchers had attempted to develop effective methods to remove them. The most successful surface-related multiple elimination method was proposed based on data-driven theory. However, the elimination effect was unsatisfactory due to the existence of amplitude and phase errors. Although the subsequent curveletdomain multiple–primary separation method achieved better results, poor computational efficiency prevented its application. In this paper, we adopt the cubic B-spline function to improve the traditional curvelet multiple matching method. First, select a little number of unknowns as the basis points of the matching coefficient; second, apply the cubic B-spline function on these basis points to reconstruct the matching array; third, build constraint solving equation based on the relationships of predicted multiple, matching coefficients, and actual data; finally, use the BFGS algorithm to iterate and realize the fast-solving sparse constraint of multiple matching algorithm. Moreover, the soft-threshold method is used to make the method perform better. With the cubic B-spline function, the differences between predicted multiple and original data diminish, which results in less processing time to obtain optimal solutions and fewer iterative loops in the solving procedure based on the L1 norm constraint. The applications to synthetic and field-derived data both validate the practicability and validity of the method.

7

Research on the statistical characteristics of crosstalk in naval ships wiring harness based on Polynomial Chaos Expansion method

Chi Y., Li B., Yang X., Wang T., Yang K., Gao Y.

Polish Maritime Research

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2017

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S 2

205--214

EN

Crosstalk in wiring harness has been studied extensively for its importance in the naval ships electromagnetic compatibility field. An effective and high-efficiency method is proposed in this paper for analyzing Statistical Characteristics of crosstalk in wiring harness with random variation of position based on Polynomial Chaos Expansion (PCE). A typical 14-cable wiring harness was simulated as the object of research. Distance among interfering cable, affected cable and GND is synthesized and analyzed in both frequency domain and time domain. The model of naval ships wiring harness distribution parameter was established by utilizing Legendre orthogonal polynomials as basis functions along with prediction model of statistical characters. Detailed mean value, mean square error, probability density function and reasonable varying range of crosstalk in naval ships wiring harness are described in both time domain and frequency domain. Numerical experiment proves that the method proposed in this paper, not only has good consistency with the MC method can be applied in the naval ships EMC research field to provide theoretical support for guaranteeing safety, but also has better time-efficiency than the MC method. Therefore, the Polynomial Chaos Expansion method.

8

Analysis and experiments on sea load and fastened mechanics on pipe clamps

Wang Z., Zhang B., Wang T.

Polish Maritime Research

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2017

|

S 2

74--80

EN

When an offshore oil field completed and put into production, new subsea pipelines and the new cable need to be established. Cable protection pipe clamp is used to fix cable protection pipe on the jacket. In order to avoid the problem of traditional steel structure clamp splice, counterpoint, fastening difficulty when installed cable protection pipe under water, reduce the risk and workload of under water, This paper develop a new type of portable connecting riser clamp –“backpack clamp” which solve the riser cable protection pipe difficult underwater installation problem. The main structure of backpack clamp used three valves type structure. The load characteristic of a clamping device was determined by the Morison equation which was a classical theory. Clamp device underwater mechanics analysis model was established. The minimum tension pre-tightening force was determined. The results show that the strength of the base meets the requirements after strength analysis with finite element analysis method, stability and strength experiments, which means the clamp based on resin matrix composite is feasible.

9

Characterization and Application of Al/Ni Reactive Multilayers in Exploding Foils

Wang T., Zeng Q., Li M.

Central European Journal of Energetic Materials

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2017

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Vol. 14, no. 3

547--558

EN

A self-propagating reaction achieved by initiating an Al/Ni reactive multilayer foil can generate significant heat. The interdiffusion rate of the reactants plays an important role in the foils properties and is mainly affected by premixing and the bilayer thickness. The present research aims to characterize Al/Ni multilayer foils and to investigate their influence on an exploding foil initiator. Samples with different bilayer thicknesses were fabricated by magnetron sputtering. The heat released and the flame velocity were characterized. Foils with a stored energy of about 1100 J/g were prepared and the heat released revealed the existence of a 4 nm premixing layer. The analytical model proposed by Mann was employed to match the measured flame velocities; the fitted model showed good agreement with the experimental results. To make a comparison, Cu and Al/Ni exploding foils with the same bridge size were fabricated and tested in the identical discharge circuit. The results showed that the energy deposition ratio of an Al/Ni foil was 67-69%, while the value for Cu was only 39-45%, which indicated that Al/Ni multilayers could effectively increase the energy utilization of an initiator. Larger average flyer velocities were also observed with the Al/Ni initiators.

10

Acoustic characteristics of damped metamaterial plate with parallel attached resonators

Wang T., Sheng M. P., Guo Z. W., Qin Q. H.

Archives of Mechanics

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2017

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Vol. 69, nr 1

29--52

EN

An acoustic metamaterial consisting of a homogeneous damped plate with parallel attached resonators is presented. Theoretical analysis shows that the metamaterial plate can generate multiple resonant-type band gaps and the lower-bound frequency of each band gap coincides with the resonance frequencies of the resonators. The parallel arrangement of resonators, compared with the metamaterial plate with resonators attached in series reported by Peng et al. (2015), results in a wider second band gap with a lower edge, while the first band gap is almost the same, creating therefore an easier combination of the multiple band gaps into a wider one. It is noted that damping has a significant influence on the band gaps and the effective mass density (especially for the damping of resonators). Specifically, it can be concluded that damping cannot be neglected in practical engineering applications, damping in the material of the host plate can smooth and lower the responses in the whole frequency range, especially in the higher frequency range, and a high level of damping of resonators deactivates the effect of band gaps. Such weak/damped resonators actualise the metamaterial damping poorly, and rather tend only to contribute to the overall damping such as the damping of the host plate.

11

Inverse data-space multiple elimination with 3D curvelet sparsity promotion

Wang T., Wang D., Wang T., Tian M.

Acta Geophysica

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2017

|

Vol. 65, no. 6

1197--1205

EN

This paper describes an effective implementation of the inverse data-space multiple elimination method via the three-dimensional (3D) curvelet domain. The method can separate the surface-related operator (A) and primaries (P0) through seismic data matrix inversion. A 3D curvelet transform is introduced to sparsely represent the seismic data in the inverse data space. Hence, this approach is suitable for obtaining an accurate solution because of its multiscale and multidirectional analysis properties. The L1 norm is used to promote sparseness in the transform domain. Then, a high-fidelity separation of the operator (A) and the primaries (P0) is realized. The proposed method is applied to synthetic data from a model containing a salt structure. We compare the results with that of the traditional inverse data-space multiple elimination method and also with that of two-dimensional surface-related multiple elimination. The findings fully demonstrate the superiority of the proposed method over the traditional inverse method; moreover, the proposed method protects the primary energy more effectively than the SRME method.

12

Closed-loop SRME based on 3D L1-norm sparse inversion

Wang T., Wang D., Sun J., Hu B., Liu C.

Acta Geophysica

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2017

|

Vol. 65, no. 6

1145--1152

EN

In many situations, the quality of seismic imaging is largely determined by a proper multiple attenuation as preprocessing step. Despite the widespread application of surface-related multiple elimination (SRME) and estimation of primaries by sparse inversion (EPSI) for the removal of multiples, there still exist some limitations in the process of prediction and subtraction (SRME) or inversion (EPSI), which make the efficiency of multiple attenuation less satisfactory. To solve these problems, a new fully data-driven method called closed-loop SRME was proposed, which combines the robustness of SRME and the multi-dimensional inversion strategy of EPSI. Due to the selection of inversion approach and constraint, primary estimation by closed-loop SRME may fall into a local optimum during the solving process, which lowers the accuracy of deep information and weakens the continuity of seismic events. To avoid these shortcomings, we first modified the solving method for closed-loop SRME to an L1 norm-based bi-convex optimization method, which stabilizes the solution. Meanwhile, in the L1 norm constraint-based optimization process, the 3D sparsifying transform, being a 2D Curvelet-1D wavelet transform, is brought in as a 3D sparse constraint. In the 3D sparsifying domain, the data become sparser, thus making the result of optimization more accurate, the information of seismic events more continuous and the resolution higher. Examples on both synthetic and field data demonstrate that the method proposed in this paper, compared with the traditional SRME and closed-loop SRME, have an excellent effect on primary estimation and suppress multiples effectively.

13

Design method of winch driven by contactless magnetic coupling under deepwater

Zhang B., Wang Z., Wang T., Yu H. J.

Polish Maritime Research

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2015

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S 1

95--99

EN

Through the combination subject of scientific research, the design method of the winch driven by contactless magnetic coupling is researched for the core purpose of the turning shaft sealing in a deepwater environment. This method has six design phases, including domestic and foreign information query and retrieval, graphic analyses of relevant structures, innovative design of 2D assembly sketches, a theoretical computation of structure parameters, the 3D modeling and motion simulation and engineering drawing. This method is of generality, which can provide examples for the postgraduate students and engineering personnel in self-renovation design of scientific research.

14

Phytoremediation of phenol using Polygonum orientale and its antioxidative response

Wang K., Cai J., Xie S., Feng J., Wang T.

Archives of Environmental Protection

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2015

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Vol. 41, no. 3

39--46

EN

Polygonum orientale with beautiful red flowers can be found as one dominant species in the vicinity of most water bodies and wetlands in China. However, its phytoremediation potential has not been sufficiently explored because little is known about its resistance to inorganic or organic pollutants. We investigated P. orientale response to low and moderate levels of phenol stress (≤ 80 mg L-1). Endpoints included phenol tolerance of P. orientale and the removal of the pollutant, antioxidant enzyme activities, damage to the cell membrane, osmotic regulators and photosynthetic pigments. In plant leaves, phenol stress significantly increased the activities of peroxidase (POD) and catalase (CAT), as well as the contents of proline, soluble sugars and carotenoids, whereas superoxide dismutase (SOD), H2O2 and electrolyte leakage (EL) levels remained unaltered. On the other hand, there were significant decreases of soluble protein and chlorophyll contents. We demonstrated that, in combination with phenol tolerance and its removal, P. orientale has efficient protection mechanisms against phenol-induced oxidative damage (≤ 80 mg L-1). We propose that P. orientale could be used as an alternative and interesting material in the phytoremediation of phenol.

15

Improvements on the HVDC Reliability Assessment Index System considering preventive maintenance

Wang T., Guan L.

Eksploatacja i Niezawodność

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2014

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Vol. 16, no. 4

629--636

EN

This paper proposes two novel reliability indexes for HVDC and a risk evaluation system for quantifying the risk brought by HVDC outage. Based on a proactive and preventive strategy of maintenance arrangement, the paper puts forward the “Power Availability” index to correct the situation that Energy Availability leads to inconsistent problems with power system reliability and security in the process of application. Then, the paper introduces the quantitative evaluation method which provides an effective analysis tool for scheduling department to arrange maintenance during the appropriate time by judging the operation risk. Based on this method, the index of “Active Planned Energy Unavailability” is put forward in order to encourage the scheduling department to arrange maintenance initiatively according to the power grid risk. It could change and improve the maintenance mode of HVDC using the guiding role of the reliability index. Blend the proposed new index into the original reliability index system of HVDC, sphere of application and the assessment objects will not only be limited to the equipment department and the dispatching department, power grid corporations will also be involved. Finally, this paper chooses the China Southern Power Grid as the simulation and analysis case. The results demonstrate a practical application of the proposed procedure and method.

PL

Niniejszy artykuł proponuje dwa oryginalne wskaźniki niezawodności dla linii wysokiego napięcia prądu stałego (HVDC) oraz system oceny ryzyka dla kwantyfikacji ryzyka na skutek przerw w dostawie HVDC. W oparciu o aktywną i prewencyjną strategię konserwacji, artykuł proponuje wskaźnik „Power Availability (Dostępności mocy)” w celu naprawy sytuacji, gdy Dostępność Energii prowadzi do niespójnych problemów z niezawodnością systemu elektroenergetycznego i bezpieczeństwem w procesie eksploatacji. Następnie artykuł wprowadza metodę oceny ilościowej, który zapewnia skuteczne narzędzie analizy dla działu planowania tak, aby można było zarządzać konserwację we właściwym momencie dzięki odpowiedniej ocenie ryzyka operacyjnego. Na bazie tej metody, zaproponowano wskaźnik „Aktywnego planowania niedostępności energii” w celu zachęcenia działu planowania do ustalania konserwacji zgodnej z poziomem ryzyka sieci energetycznej. Może to zmienić i poprawić tryb konserwacji HVDC za pomocą wskaźnika niezawodności. Proponowany nowy wskaźnik mógłby zostać wprowadzony do pierwotnego systemu wskaźników niezawodności HVDC i mógłby znaleźć zastosowanie i służyć ocenie obiektów nie tylko w działach sprzętu i dziale dyspozytorskim ale także w firmach eksploatujących sieci energetyczne. Na potrzeby symulacji i analizy, artykuł omawia przedsiębiorstwo China Southern Power Grid. Wyniki pokazują praktyczne zastosowanie proponowanej procedury i metody.

16

Simultaneous determination of gallic acid, protocatechuic acid, catechin, epicatechin, quercetin and kaempferol in Chinese chestnut (Castanea mollissima blume) kernel by high-performance liquid chromatography with diode array detection

Wang T., Yang Y. D., Du B., Yu S., Hou W. L.

Acta Chromatographica

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2014

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Vol. 26, no. 3

539--550

EN

Chestnut exhibits anti-inflammatory, styptic, anti-diarrhea, and analgestic effects as a traditional Chinese medicine. There is increasing evidence that shows that the consumption of chestnuts has become more important in human nutrition due to the health benefits provided by the antioxidants. The phenolic compounds are responsible for major bioactivities, such as anti-tumor and anti-oxidation. A high-performance liquid chromatography (HPLC) method with diode array detection (DAD) was established for the simultaneous determination of six phenolic compounds (gallic acid, GA; protocatechuic acid, PR; catechin, CA; epicatechin, EP; quercetin, QU; kaempferol, KA) in Chinese chestnut (Castanea mollissima blume) kernel. The sample followed by separation on Eclipse XDB-C18 column (150 × 4.6 mm, id., 5 μm) with gradient elution of methanol-1.0% acetate acid solution as a mobile phase, at a temperature of 30°C, under the ratio of 1.2 mL min-1, with 5 μL injection volume, and multi-wavelength synthesis was used with DAD. The correlation coefficients were larger than 0.999, the recoveries were 97.58% for GA, 100.41% for PA, 96.23% for CA, 101.38% for QU, 99.15% for EP, and 98.60% for KA, relative standard deviation (RSD) were 1.04% for GA, 1.21% for PA, 1.09% for CA, 1.19% for QU, 1.06% for EP, and 1.20% for KA. This method was applied for the determination of phenolics in chestnut kernel and was found to be fast, sensitive, and suitable.

17

Robust Control for Nonlinear TCP Time-delay Dynamic Network Systems

Sun P., Wang T.

Przegląd Elektrotechniczny

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2012

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R. 88, nr 7b

257--260

EN

This paper presents a robust control scheme for nonlinear TCP time-delay dynamic network systems. By introducing the interference and time-delay to improve the nonlinear model, the objective of the work described here was to express various interference and time-delay factors in the actual network running environment. Using proper coordinate transformation, evaluation signal and energy storage function, the robust controller was guaranteed to satisfy nonlinear L2 gain performance index. The desired queue size was achieved, and the asymptotic stability was obtaineed for nonlinear TCP time-delay dynamic network systems. In the paper this method ameliorates the complex algorithms of nonlinear TCP time-delay dynamic network systems, simplifies derivation and achieves more easily robust control algorithms for nonlinear dynamic network systems. Finally, the simulation results confirm the feasibility and effectiveness.

PL

W artykule zaproponowano odporny system sterowania nieliniowym system sieciowym TCP z opóźnieniem czasowym. Zamodelowano róznego rodzaju interferencje i opóźnienia. Otrzymano pożądany rozmiar kolejki oraz stabilność systemu. Zaproponowana metoda stanowi uproszczenie możliwości sterowania nieliniowymi systemami sieciowymi.

18

Experiments for Verification of the Effectiveness of Smoke Control System in a Typical Subway Station

Tan J., Xie Y., Wang P., Wang T., Hu B.

Przegląd Elektrotechniczny

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2012

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R. 88, nr 1b

78-81

EN

In order to verify the effectiveness of smoke control system in subway station, a series of hot smoke tests were done on real platform and station hall. The temperature of smoke layer and roof are measured by thermocouple and Infrared Thermograph, and the results showed the maximum temperature of platform and station hall roof can reach to 61.4°Cand 55.7°C. The wind speed on stairs are large enough to make the smoke don’t enter into station hall (on platform test) and platform (on station hall test).There is a blind area on both sides of platform on the process of mechanical exhaust smoke. It is not easy to exhaust when the smoke flow into both side of platform. The smoke can be exhausted when the air vents are set on both side of platform. There is no blind area of smoke exhaust on station hall in test.

PL

Przedstawiono system kontroli palaenia stacji kolei podziemnej. Temperatura mierzona jest czujnikiem termoelektrycznym i przy pomocy termografii podczerwonej. W systemie przewidziano możliwości badania dymu z uwzględnieniem przepływów powietrza.

19

Analysis of jacking force for rectangular pipe-jacking machine

Li H., Yang Y., Tu X., Wang T.

Przegląd Elektrotechniczny

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2012

|

R. 88, nr 9b

200-203

EN

For the electrical control system of push pipe driving machine, the adjustment of jacking force is critical to balancing the resistance force and moving the pipe string forward. This force should be well under control so as to avoid both the collapse (active failure) and the blow-out (passive failure) of the soil mass near the tunnel face. The aim of this paper is to determine the collapse and blow-out face jacking force of a rectangular tunnel. The analysis is carried out in the framework of the kinematic method of limit analysis theory. The numerical results obtained are presented and analyzed.

PL

W maszynach do przeciskania rur istotną role odgrywa siła przecisku (jacking force). W artykule analizuje się tę siłę dla prostokątnego tunelu.

20

A Novel RNA Genetic Algorithm for the Parameter Estimation of the Ordinary Differential Equations with Multiple Solutions

Si X. Y., Fang G. H., Yang F., Guo W., Wang T., Si X. H.

Przegląd Elektrotechniczny

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2012

|

R. 88, nr 9b

118-120

EN

In fluid mechanics, to obtain the multiple solutions in ordinary differential equations is always a concerned and difficult problem. In this paper, a novel RNA genetic algorithm (NRNA-GA) inspired by RNA molecular structure and operators is proposed to solve the parameter estimation problems of the multiple solutions in fluid mechanics. This algorithm has improved greatly in precision and the success rate. Multiple solutions can be found through changing accuracy and search coverage and multi-iterations of computer. At last, parameter estimation of the ordinary differential equations with multiple solutions is calculated. We found that the result has great accuracy and this method is practical.

PL

W artykule zaproponowano nowy algorytm genetyczny NRNA-GA inspirowany strukturą molekularną RNA przeznaczony do rozwiązywania równań z wieloma rozwiązaniami w mechanice cieczy.