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On the effect of pitch and yaw angles in oblique impacts of smallcaliber projectiles

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Defence Technology（防务技术） 2024年第1期31卷 73-94页

作者： Teresa Fras French-German Research Institute of Saint-Louis(isl) Saint-LouisFrance

A terminal ballistic analysis of the effects of 7.62 mm × 51 AP P80 rounds on inclined high-strength armor steel plates is the focus of the presented *** findings of an instrumented ballistic testing combined with 3D advanced numerical simulations performed using the IMPETUS Afea? software yielded the *** experimental verification proved that slight differences in the pitch-andyaw angles of a projectile upon an impact caused different damage types to the projectile’s *** residual velocities predicted numerically were close to the experimental values and the calculated core deviations were in satisfactory agreement with the experimental *** extended matrix of the core deviation angles with combinations of pitch-and-yaw upon impact angles was subsequently built on the basis of the numerical *** presented experimental and numerical investigation examined thoroughly the influence of the initial pitch and yaw angles on the after-perforation projectile’s performance.

关键词： Ballistic impact Small-caliber projectile Pitch and yaw impact angles Shadowgraphy IMPETUS Afea Numerical simulations

Shock Wave Smearing by Passive Control

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Journal of Thermal Science 2006年第1期15卷 43-47,42页

作者： Piotr DOERFFER Oskar SZULC Rainer BOHNING IMP PAN Fiszera 14 PL-80 952 Gdansk Poland isl Universitat Karlsruhe Karlsruhe Germany

Normal shock wave, terminating a local supersonic area on an airfoil, limits its performance and becomes a source of high speed impulsive noise. It is proposed to use passive control to disintegrate the shock wave. Details of the flow structure obtained by this method are studied numerically. A new boundary condition has been developed and the results of its application are verified against experiments in a nozzle flow. The method of shock wave disintegration has been confirmed and detailed analysis of the flow details is presented. The substitution of a shock wave by a gradual compression changes completely the source of the high speed impulsive noise and bears potential of its reduction.

关键词： transonic flows shock wave boundary layer interaction passive control.

Blast disruption using 3D grids/perforated plates for vehicle protection

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Defence Technology（防务技术） 2023年第7期25卷 60-68页

作者： Therese Schunck Dominique Eckenfels Laurent Sinniger French-German Research Institute of Saint-Louis ISL5 Rue Du General Cassagnou68300Saint-LouisFrance

In this work, blast disruption and mitigation using 3D grids/perforated plates were tested for underbelly and side protection of vehicles. Two vehicle simulants were used: a small-scale one for side vehicle protection assessment and a true-to-scale simulant for underbelly protection testing. The deformation of target plates was assessed. These were either unprotected or protected by three different types of disruptors. The first disruptor was made of a sandwich structure of two perforated plates filled with a thin aluminum structure allowing the air to pass through. The two other disruptors were made of pieces of cast metallic foam. Two different kinds of foams were used: one with large cells and the second one with small cells. Beforehand, the mitigation efficiency of the disruptors was evaluated using an explosivedriven shock tube(EDST). The experiments showed that blast disruption/mitigation by 3D grid/perforated plate structures was not suitable for vehicle side protection. However, 3D grids/perforated structures proved to be relatively effective for underbelly protection compared to an equivalent mass of steel.

关键词： Blast Mitigation Perforated plates 3D grids Vehicle protection

Experimental and Analytical Analysis of Perforated Plate Aerodynamics

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Journal of Thermal Science 2003年第3期12卷 193-197页

作者： JürgenZierep RainerBohning Piotr Doerffer isl Karlsruhe University Kaiserstr.12 D-76 128 Karsruhe GermanyISL Karlsruhe University Kaiserstr.12 D-76 128 Karsruhe GermanyIMP PAN Fiszera 14 PL-80 952 Gdansk Poland

Perforated walls and transpiration flow play an important role in aerodynamics due to an increasing interest in application of flow control by means of blowing and/or suction. An experimental study was carried out which has led to the determination of a transpiration flow characteristics in the form of a simple formula that is very useful in modelling such flows. In connection to this relation a method of 'aerodynamic porosity' determination has been proposed which is much more reliable than geometric description of the porosity. A theoretical analysis of the flow through a perforation hole was also carried out. The flow was considered as compressible and viscous. The gasdynamic analysis led us to a very similar result to the relation obtained from the experiment. The adequacy of the theoretical result is discussed in respect to the experiment.

关键词： transonic flow flow control transpiration flow perforated walls blowing and suction.

The Cemented Material Dam： A New, Environmentally Friendly Type of Dam

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Engineering 2016年第4期2卷 490-497页

作者： Jinsheng Jia Michel Lino Feng Jin Cuiying Zheng China Institute of Water Resources and Hydropower Research Beijing 100038 China isl Ingeierie Saint-Jean-de-Luz 64500 France Tsinghua University Beijing 100084 China

The first author proposed the concept of the cemented material dam （CMD） in 2009. This concept was aimed at building an environmentally friendly dam in a safer and more economical way for both the dam and the area downstream. The concept covers the cemented sand, gravel, and rock dam （CSGRD）, the rockfill concrete （RFC） dam （or the cemented rockfill dam, CRD）, and the cemented soil dam （CSD）. This paper summarizes the concept and principles of the CMD based on studies and practices in projects around the world. It also introduces new developments in the CSGRD, CRD, and CSD.

关键词： Cemented material dam Cemented sand, gravel, and rock dam Rockfill concrete dam Cemented rockfill dam Cemented soil dam Material properties

Adsorption Chronopotentiometric Determination of Aluminum in Drinking Waters by Cupferron

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Chinese Chemical Letters 1998年第10期9卷 949-951页

作者： Shu Ping BI Yi GONG Lei YE Jing LI(Department of Chemistry, Naming University, Naming 210093 State Pilot Laboratory of Coast and island Exploitation, Naming University, Naming 210093) Department of Chemistry Nanjing University Nanjing 210093 China State Pilot Lab. Coast/isl. E. Nanjing University Nanjing 210093 China

A novel and very sensitive electroanalytical method, based on the adsorption chronopotentiometry in the presence of cupferron, was developed for the determination of trace levels of aluminum. The working linear range is 2x10(-9)-9x10(-7) mol/L and the detection limit is 1x10(-9) mol/L. It has been successfully applied to the determination of Al in various drinking-water samples.

关键词： aluminum cupferron adsorption chronoptentiometry drinking waters

Late Quaternary diatom and sea level changes in estuarine plain of the Jiulong River

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Acta Oceanologica Sinica 1998年第4期17卷 509-518页

作者： Chen Wenrui, (State Pilot Laboratory of Coast and island Exploitation, Naning University, Naning 210093, China)Lan Dongzhao and Chen Chenghui (Third Institute of Oceanography, State Oceanic Administration, Xiamen 361005, China) State Pilot Lab. Coast isl. E. Nanjing University Nanjing 210093 China Third Institute of Oceanography State Oceanic Administration Xiamen 361005 China

Four units and twenty-four zones of diatom have been discerned in the Borehole ZK5 in the estuarine plain of the Jiulong River, Fujian Province. Comprehensive analysis of these, together with microbiological assemblages and age determinations in some other boreholes, shows that during the Late Wurm Glacial, sea level of the study area rose and fell frequently, but had principally been in the environments of estuary-bay. This mainly resulted from the tectonic subouction. In this period 3 low sea levels occurred. at 18, 16 and 12 kaBP respectively. During Holocene, sea weter intruded massively and the sea level over the transgnaion maximum had been 5-10 m higher than that of the present.

关键词： Late Quaternary diatom sea level change estuarine plain the Jiulong River

堆石混凝土坝概述及下一代混凝土坝施工技术展望

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Engineering 2024年第1期32卷 99-105页

作者： Feng Jin Duruo Huang Michel Lino Hu Zhou Department of Hydraulic Engineering Tsinghua UniversityBeijing 100084China isl Ingénierie International Commission on Large DamsParis 75016France

Over the past few decades,one of the most significant advances in dam construction has been the inven-tion of the rock-filled concrete(RFC)dam,which is constructed by pouring high-performance self-compacting concrete(HSCC)to fill the voids in preplaced large *** innovative use of large rocks in dam construction provides engineers with a material that requires less cement consumption and hydration heat while enhancing construction efficiency and environmental ***,two fundamental scientific issues related to RFC need to be addressed:namely,the pouring compactness and the effect of large rocks on the mechanical and physical properties of *** article provides a timely review of fundamental research and innovations in the design,construction,and quality control of *** for next-generation concrete dams are discussed from the perspectives of envi-ronmental friendliness,intrinsic safety,and labor savings.

关键词： Rock-filled concrete dam Pouring compactness Effect of large rocks Intelligent quality control Unmanned dam construction

Reconstruction of the Unsteady Supersonic Flow around a Spike Using the Colored Background Oriented Schlieren Technique

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Journal of Flow Control, Measurement & Visualization 2013年第2期1卷 69-76页

作者： Friedrich Leopold Masanori Ota Daniel Klatt Kazuo Maeno French-German Research Institute of Saint-Louis (isl) Saint-Louis France Graduate School of Engineering Chiba University Chiba Japan

In this paper, the improved Background Oriented Schlieren technique called CBOS (Colored Background Oriented Schlieren) is described and used to reconstruct the density fields of three-dimensional flows. The Background Oriented Schlieren technique (BOS) allows the measurement of the light deflection caused by density gradients in a compressible flow. For this purpose the distortion of the image of a background pattern observed through the flow is used. In order to increase the performance of the conventional Background Oriented Schlieren technique, the monochromatic background is replaced by a colored dot pattern. The different colors are treated separately using suitable correlation algorithms. Therefore, the precision and the spatial resolution can be highly increased. Furthermore a special arrangement of the different colored dot patterns in the background allows astigmatism in the region with high density gradients to be overcome. For the first time an algebraic reconstruction technique (ART) is then used to reconstruct the density field of unsteady flows around a spike-tipped model from CBOS measurements. The obtained images reveal the interaction between the free-stream flow and the high-pressure region in front of the model, which leads to large-scale instabilities in the flow.

关键词： Unsteady Spike Flow Reconstruction Density Field Schlieren Technique