Unit Volume Research Articles

Formation of a uniform velocity profile in the section of a profiled channel of a reference installation

The velocity profiles in gravity and pressure channels of flow diverters in reference installations in the field of liquid flow and quantity measurements are studied. The design shortcomings of reference installations that do not allow obtaining a flow velocity profile close to uniform in the sections of pressure nozzles over a long period of reference installation operation are described. It is shown that the placement of various straightening devices in the profiled channels and pressure nozzles of flow diverters of reference installations does not lead to obtaining a flow velocity profile close to uniform. An approach to profiling the gravity channel of the flow diverter is proposed, which allows obtaining a velocity profile close to uniform. An experimental justification of the hydraulic efficiency of the geometry of the flow part of the profiled channel of the flow diverter of the EU-3 reference installation from the State Primary Special Standard of Units of Mass and Volume of Liquid in a Flow, Mass and Volume Flow Rates of Liquid GET 63-2019 is presented. The influence of the flow velocity profile shape in the section of the profiled channel of the flow switch and the stability of the main hydro- and thermodynamic parameters of the water flow (flow rate, absolute pressure and temperature) in the pressure pipeline on the metrological characteristics of the reference installation is substantiated. Experimental studies of the velocity profile of the free-flow water flow in the section of the profiled channel are performed using high-speed total pressure meters and Pitot tubes. Close to uniform water flow velocity profiles in the section of a profiled channel were obtained for free flow in the range of investigated Reynolds numbers Re=(35...300)·103. The results of maintaining the stability of the specified value of the mass flow rate of water over a long period of time are presented. The equations for calculating the mass of water during transient processes are written down, taking into account the change in the thickness of the water flow and flow rate from zero to specified values. The presented approach and the obtained results are useful for manufacturers of reference installations and are relevant in the design, creation and modernization of profiled channels of flow switches of reference installations.

Development of mesoporous magnetic nanoparticles supported idarubicin and investigation of apoptotic and cytotoxic effects on cancer cell lines.

Many methods are used for cancer treatment, especially chemotherapy. In addition to the their therapeutic effects, chemotherapeutic drugs also have serious disadvantages, such as not being cell and tissue-specific, causing toxicity in many tissues, and developing drug resistance. Many methods, especially nanocarriers, have been designed to overcome these disadvantages. In this study, we synthesized mesoporous silica iron oxide nanoparticles with different pore diameters and loaded idarubicin (6MFe3O4-NH2-IDA and 35MFe3O4-NH2-IDA). The synthesized molecules were characterized using FT-IR, XRD, and SEM methods. The cytotoxic effects of unbound idarubicin and idarubicin-loaded nanoparticles on MCF7 and HL-60 cell lines were examined by MTT test. Additionally, the expression of anti-apoptotic (Survivin and BCL-2) and apoptotic (BAX, PUMA, and NOXA) genes of the nanoparticles were measured by PCR method. As a result of the analyses, it was seen that nanoparticles with the desired properties and sizes were synthesized. In MTT analysis, it was observed that both nanoparticles dramatically decreased the IC50 value in cell lines. However, the 35MFe3O4-NH2-IDA molecule was found to have lower IC50 values. IC50 values ​​for pristine IDA, 6MFe3O4-NH2, and 35MFe3O4-NH2 at 24h were found to be 3.56, 1.24 and 0.25 µM in the MCF7 cell line and 4.15, 1.16 and 0.34 µM in the HL-60 cell line, respectively. Additionally, apoptotic gene expression increased, and anti-apoptotic gene expression decreased. Our study demonstrates that the effectiveness of idarubicin can be significantly enhanced by its application with mesoporous nanocarriers. This enhancement is attributed to the controlled release of idarubicin from the nanocarrier, which circumvents drug resistance mechanisms, improves drug solubility, and increases the drug-carrying capacity per unit volume due to the porous structure of the carrier. These findings underscore the potential of the synthesized nanocarrier in cancer treatment and provide a clear direction for future research in this field.

Interaction between calcium hydroxide and calcium-alumino-silicate-hydrate on micromechanical properties

Calcium-alumino-silicate-hydrate (C-A-S-H) and calcium hydroxide (CH) are the two primary hydration products that play crucial roles in the mechanical properties of cementitious materials, particularly in the viscoelastic behavior known as creep. This study used hydrated C3S and a mixture of the synthesized C-A-S-H and CH to identify the interactions between CH and C-A-S-H. The interactions that dominate the mechanical properties mainly operate from physical and chemical perspectives. CH exhibited a filling effect on C-A-S-H in the physical interactions, demonstrating multi-scale particle packing efficiency. The particle size of CH per unit volume of the mixture was proposed as a critical parameter for the filling effect. Regarding chemical interactions, the synthetic system exhibits interactions primarily through van der Waals forces through compaction. In contrast, the interaction in the hydration system primarily originates from the strong atomic bonding between C-A–S–H and CH at the nanoscale.

Exploring oligosaccharide effects on wheat starch gelatinization: Mechanisms and oligosaccharide structural perspectives

Controlling the gelatinization of starch is vital for achieving desired food design, and sugars and oligosaccharides (OSs) have a significant impact on the gelatinization temperature (Tgel) of starch. This study delved into the effects of sucrose, maltotetraitol, and ten glucose-based OSs with different glycosidic linkage patterns, degrees of polymerization (DP), and linear or cyclic structures on the Tgel of wheat starch. The objective of this study was to uncover the underlying mechanisms by which OSs alter Tgel to support the design and use of OSs for sugar reduction in baked goods. Findings underscore the notable impact of both OS concentration and type on Tgel. Increases in OS concentration resulted in Tgel elevation, closely linked to changes in water activity and effective water volume fraction (φw,eff). Among the same DP OSs, a higher effective number of hydroxyl groups available for hydrogen bonding per unit volume of the solute (NOH,S/Vs) corresponded to increased Tgel, indicating higher hydroxyl density in OSs leads to an increased number of hydrogen bond formation between OSs and starch that stabilizes the structure. Of particular note is that isomaltose (α-1,6 linkage) significantly elevated the Tgel more than the other DP2 OSs, trehalose (α-1,1 linkage), kojibiose (α-1,2 linkage), and maltose (α-1,4 linkage), even with low NOH,S/Vs. This underscores the importance of OS structural flexibility in antiplasticizing starch. The study enriches our understanding of how OSs influence starch Tgel relative to the effects of sucrose, emphasizing the roles of intermolecular hydrogen bonding and OS structural flexibility in elevating starch Tgel in a manner which is beneficial for maintaining the texture and structural properties of reduced-sugar baked goods.

Stress and power as a response to harmonic excitation of a fractional anti‐Zener and Zener type viscoelastic body

AbstractThe stress as a response to strain prescribed as a harmonic excitation is examined in both transient and steady state regime for the viscoelastic body modeled by thermodynamically consistent fractional anti‐Zener and Zener models by the use of the Laplace transform method. Assuming strain as a sine function, the time evolution of power per unit volume, previously derived as a sum of time derivative of a conserved term, which represents the rate of change of stored energy, and a dissipative term, which represents dissipated power, is investigated when expressed through the relaxation modulus and creep compliance. Further, two forms of energy and two forms of dissipated power per unit volume are examined in order to see whether they coincide.

Development and evaluation of mixing performance of new type pitched paddle impeller (HR1000) for wastewater treatment

AbstractSATAKE MultiMix Corporation developed a new type of pitched paddle impeller for low power consumption turbulent mixing for wastewater treatment and its performance was evaluated by measuring power consumption, mixing time, and particle suspension. The power number of the new impeller was lower than that of the existing pitched paddle, which could be constructed by modifying the correlation equation. For the same power consumption per unit volume, the mixing performance was almost the same as that of other axial flow impellers. The particle suspension performance was also the same as that of other axial flow impellers.

Stochastic or deterministic: Duality of fatigue behaviour of 3D-printed meta-biomaterials

The two deformation modes of meta-biomaterials during cyclic loading have been revealed: stochastic and deterministic strut failure processes. Biomimetic Voronoi structures with a range of strut thicknesses and number of cells per unit volume are printed. We show that when the strut thickness is 200 μm or above, the fatigue fracture process of the lattice is deterministic and the fatigue scatters are below 15%. As the strut is thinned to 150 μm, the local failures occur randomly within the structure, which may lead to a high fatigue scatter (>30%). The two distinct behaviours result from the processing limit of the laser powder bed fusion technique. We demonstrate that the fatigue scatter and the location of the failure process within the lattice are related to the probability that a cluster of unconnected struts larger than a critical value can exist within the lattice. Unlike solid parts, porosity hardly triggers any damage in metallic lattices during cyclic deformation. The discovery of the Janus-like failure process opens up our understanding of meta-biomaterials and defines the pathway towards the design of mechanically durable intricate implants.

Predictive factors for prolonged operative time in ureteroscopic lithotripsy for ureteral stones A retrospective cohort study.

A prolonged operative time of lithotripsy with ureteroscopy for urolithiasis increases the risk of infectious complications; however, few reports have investigated the factors prolonging the operative time for ureteral stones. We investigated the factors associated with longer operative time in ureteroscopy for ureteral stones. This retrospective cohort study analyzed patients who underwent retrograde ureteroscopic lithotripsy for ureteral stones and achieved an endoscopic stone-free status between April 2019 and July 2022. Patients were classified into two groups based on an operative time of ≥90 minutes or <90 minutes. We compared the patient and stone characteristics and surgical outcomes, and investigated the factors associated with a prolonged operative time. The cohort comprised 519 patients, with 58 patients in the group with an operative time of ≥90 minutes. Compared to the shorter operative time group, the longer operative time group had a significantly greater proportion of males, stone diameter, stone volume, and Hounsfield units of stone; additionally, the longer operative time group had higher prevalences of endoscopic findings of edema, polyps, and mucosa-stone adherence. Multivariable analysis showed that stone size >10 mm (odds ratio 4.05), polyps (odds ratio 2.40), and mucosal adherence (odds ratio 3.51) were significantly associated with an operative time exceeding 90 minutes. There were no significant differences between the two groups in the incidences of postoperative fever and systemic inflammatory response syndrome. Stone size, endoscopic findings of polyps, and mucosa-stone adherence were independent factors associated with a longer operative time.

A framework for seasonal groundwater banking in agricultural regions: A case study

Groundwater banking has been used for demand-oriented management of groundwater resources in semi-arid and arid regions. This paper aims to propose a new framework for seasonal groundwater banking. In this framework, crop production functions are used to estimate users' bid packages representing the price of each unit volume of water in each auction period. The bid packages, along with users' water rights, are considered inputs of an optimization model, which maximizes the profit of users participating in the groundwater bank. The main outputs of the optimization model are the volumes of exchange and storage of water, as well as the water price in the auction periods. The efficiency of the proposed framework has been evaluated by applying it to the Nough region in the Rafsanjan Plain, central Iran. An existing plan for inter-basin water transfer to this region is also considered in the water banking framework. The results illustrate that the total annual profit of all users after the establishment of the bank compared to the status quo has increased up to 43.8 %. The profit of the water-recipient basin has also increased more than 4 times compared to the existing condition. In addition, water banking with a water transfer system increases the economic productivity of water and crop production by 37.32 % and 22.41 %, respectively.

Anchoring mechanical characteristics of Ductile-Expansion bolt

The application of ductile rock bolts has been a crucial method for solving the problems of large deformations, energy absorption and stability control issues in deep rock masses. To study the anchoring mechanism of the key expansive structure, this paper proposes a novel type of bolt — the Ductile-Expansion bolt, and conducts research on anchoring mechanics, energy absorption characteristics, and failure modes of the bolt. In addition, this paper defines the concept of load-volume ratio of metal rock bolts and proves the Ductile-Expansion bolt is capable of better improving the unit volume bearing capacity of the bolt material. Furthermore, laboratory and field tests verify the Ductile-Expansion bolt had better anchoring effect than the traditional rebar bolt, with the expansion structure favorably enhancing the ductility and energy absorption performance of the bolt. Finally, this paper microscopically analyzes the crack propagation and distribution morphology of the bolts by establishing a 3D coupled numerical model based on FDM-DEM. Numerical results illustrate the interface at the variable diameter of the Ductile-Expansion bolt serves as the transition zone between high and low stress levels. The expansion structure can impose radial compression on the medium around the bolt, which can improve the bolt anchorage performance.

Composition and Characteristics of Faecal Sludge from Various Onsite Pit Technologies and User Categories in Dar es Salaam, Tanzania

This study investigates the composition and characteristics of faecal sludge (FS) from different pit technologies (cesspits, pit latrines, septic tanks) and user categories (commercial, industrial, institutional, and residential) in Dar es Salaam, Tanzania, with a view for informed treatment and resource recovery strategies. FS samples exhibited varying concentrations of pH, electrical conductivity (EC), total solids (TS), and volatile solids (VS), COD and nutrients. pH values ranged from 2.83 to 8.41, with no statistically significant differences based on pit technology type or user category. However, the extremely low pH observed in samples from industrial pits suggests possible disposal of industrial chemicals in these sanitation systems. EC levels were notably higher in pit latrines and residential areas, likely due to waste disposal practices in homes, with concentrations 3-5 times above regulatory limits, raising concerns about their impact on treatment effectiveness and re-use potential. TS and VS concentrations also varied, with cesspits showing the highest TS levels and pit latrines exhibiting higher VS, indicating fresher sludge and potential for biogas production, as reflected by a VS/TS ratio ranging from 53.32% to 70.42%. Nutrient analysis revealed elevated levels of phosphate, nitrate and ammonia, particularly in pit latrines and residential pits, highlighting both resource recovery opportunities and challenges for treatment processes. While FS generally fell into the dilute category (TS &lt; 3%), the high concentrations of other parameters underscore the need for a larger treatment footprint per unit volume of FS. The VS/TS ratio suggests that FS is not fully stabilized, indicating potential for further degradation and resource recovery. Additionally, the characteristics of FS suggest potential opportunities for deriving fertilizer and solid fuel. However, ensuring the hygiene of the sludge is crucial for its safe use, particularly in agricultural applications, and further studies are needed to confirm its sanitation.

Additive single atom values for thermodynamics IV: Formula volume, enthalpy, absolute entropy and heat capacity for ionic solids - Hydrate and anhydrate data

Atom Sums are optimized additive values for the chemical elements which may be used to predict thermochemical values of inorganic solids. Since they are based on the elements of the Periodic Table they are a complete set of parameters, subject only to the availability of reference thermochemical data. In the present publication, optimized data is presented for ambient formula unit volumes, enthalpies, entropies and heat capacities for both inorganic hydrates and anhydrates. These data complement previously published Atom Sum parameters for formation reaction entropies and for formation reaction Gibbs energies as well as complementing earlier data for undifferentiated inorganic solids.

Production of rubberized concrete utilizing reclaimed asphalt pavement aggregates and recycled tire steel fibers

The integration of waste tire elements into concrete, specifically granular rubber and discrete steel fibers, signifies a substantial advance in the pursuit of sustainable alternatives for rigid concrete pavements. This incorporation not only improves the ductility of rigid concrete pavements, but also augments their energy absorption capabilities. Similarly, replacing natural aggregates in concrete with reclaimed asphalt pavement (RAP) aggregates makes a large contribution to the reduction of negative environmental impacts, while conserving natural resources from depletion. This investigation explores the potential application of recycled rubber particles from waste tires (WTRR) and RAP aggregates as partial substitutes for natural fine aggregates, and evaluates their impact on the performance of rigid concrete pavements. Eight mixes were cast, each with two variables: (i) fine aggregate type (fine rubber (FRu) aggregates, fine asphalt (FAs) aggregates, and combinations of both types of aggregate) replacing 50 % of the natural fine aggregate; and (ii) waste tire recycled steel fibers (WTRSF) content (0 and 40 kg/m3). The axial compressive stress–strain, flexural load–deflection, and direct shear strength behaviors, together with the dry unit weight and volume of permeable voids for all concrete mixes were investigated and compared. The results show that, although the flexural and shear strengths decrease with the inclusion of FRu and/or FAs, the use of WTRSF noticeably mitigates the losses in strength that arise from the use of WTRR and/or RAP aggregates alone. The inclusion of WTRSF enhances the strain capacity of the concrete and allows the development of adequate post-peak energy absorption capacity in flexural and shear loading. Additionally, the dry unit weight of the proposed composites decreased by as much as 8 %, and their volume of permeable voids lies within the limits of high-durability concrete mixes (9–12 %). Hence, the proposed sustainable concrete composites are promising composites for rigid concrete pavement construction.

Magnetic resonance velocimetry of thin falling films

Falling film microreactors are a type of liquid–gas contactor based on a gravity-driven film flow. These devices achieve high interfacial areas per unit volume compared to other contactors. Nevertheless, they are limited by the liquid-side mass transfer. To overcome this issue, the operating conditions must be chosen in a way to enhance gas absorption and ensure efficient transfer within the film. The present study looks into the use of magnetic resonance velocimetry to study the velocity field inside of falling films at the microscale. Two parameters were considered, the channel geometry, and the volumetric flow rate. The aim was not only to determine the conditions that optimize the interfacial area, but also to showcase the capabilities and advantages of magnetic resonance velocimetry for this type of flow configuration. In addition, a straightforward mathematical model, based on the Navier–Stokes equations, is used to predict the thickness of the film, since previous approaches, mainly those of Kapitza and Nusselt, are not valid for flows at the microscale, where surface tension phenomena predominate. It was shown that the round channel yields by far the highest surface-to-volume ratio, twice as high as for the rectangular channel for the same volumetric flow rate. In addition, film breakup was not observed in the round channel even for volumetric flow rates of down to 0.27mLmin−1.

Single molecule dynamics in a virtual cell combining a 3-dimensional matrix model with random walks

Recent advances in light microscopy have enabled single molecules to be imaged and tracked within living cells and this approach is impacting our understanding of cell biology. Computer modeling and simulation are important adjuncts to the experimental cycle since they aid interpretation of experimental results and help refine, test and generate hypotheses. Object-oriented computer modeling is particularly well-suited for simulating random, thermal, movements of individual molecules as they interact with other molecules and subcellular structures, but current models are often limited to idealized systems consisting of unit volumes or planar surfaces. Here, a simulation tool is described that combines a 3-dimensional, voxelated, representation of the cell consisting of subcellular structures (e.g. nucleus, endoplasmic reticulum, cytoskeleton, vesicles, and filopodia) combined with numerical floating-point precision simulation of thousands of individual molecules moving and interacting within the 3-dimensional space. Simulations produce realistic time-series video sequences comprising single fluorophore intensities and realistic background noise which can be directly compared to experimental fluorescence video microscopy data sets.

Challenges in developing materials for microreactors: A case-study of yttrium dihydride in extreme conditions

The development of microreactor technology presents an efficient solution for providing portable electricity, catering to both human space exploration needs within our solar system and supplying power to remote Earth-bound areas. The miniaturization of nuclear reactors poses immediate new challenges for materials science with respect to the capability for controlling nuclear reactions via thermalization of highly-energetic neutrons. In a microreactor, neutron moderation takes place in compact geometries, thus new moderator materials are required to exhibit high moderating power per unit of volume. This challenge is currently being addressed through the development of transition metal hydrides, known for their strong nuclear moderation capability but to date, research on their irradiation response is limited, specifically regarding phase stability, hydrogen in-lattice retention, and their dependence on irradiation temperature and dose. Herein, we present a detailed investigation on the response of yttrium dihydride (YH2) to heavy ion irradiation. The experiments indicate that YH2 is stable up to an irradiation dose of 2 dpa and below 800°C, identified herein as a critical temperature for YH2. Our study detected the nucleation and growth of voids as a function of the irradiation temperature. They were the predominant type of radiation damage present in the microstructure of YH2 that was distinguishable from pre-existing defects in the pristine YH2 samples. Below the critical temperature, no phase transformation (degassing/dehydriding) nor amorphization occurred. Experimental results with concomitant density functional theory calculations allowed us to elaborate and propose new strategies to enhance the metal hydride performance in extreme environments.

Exploration of the adsorption and desorption performance of volatile organic compounds by activated carbon with different shapes based on fixed-bed experiments

Activated carbon (AC) has been widely used in volatile organic compounds (VOCs) treatment of industrial exhaust gases. Rather than modifying specific pore size distributions and surface properties, altering the shape of AC offers a more feasible approach to enhance its adsorption performance. This study investigates the adsorption-desorption performance of two different shaped ACs with highly similar properties for the removal of VOCs. The clover-shaped AC (CSAC) has a 27.46% lower internal void fraction and a 39.10% higher external void fraction compared to cylindrical AC (CAC), resulting in denser packing and longer contact time with VOCs. Adsorption experiments showed the CSAC has 40% longer adsorption breakthrough (BT) times for ethanol, ethyl acetate, and n-hexane on average, and 20% higher saturation adsorption capacity per unit volume. CSAC also has higher partition coefficients, with the highest values for ethanol, ethyl acetate, and n-hexane being 0.0187, 0.0382, and 0.0527 mol kg−1·Pa−1, respectively. The desorption process for selected VOCs is non-spontaneous and endothermic. Optimal desorption conditions were identified as an inlet space velocity of 3535 h−1, a desorption temperature of 150 °C, and a pulsed inlet method. To investigate the possibility of the application of CSAC in real-world scenarios, xylene was chosen as a representative industrial VOC. Results showed CSAC has 20% higher BT time and saturation adsorption capacity for xylene compared to CAC under different bed heights. The desorption efficiency for xylene on both ACs is below 40%. With increasing xylene inlet concentration, the mass transfer zone (MTZ) height initially increases but stabilizes beyond 1704 mg m−3. At identical bed heights, the MTZ height of CSAC is 29% shorter than CAC, indicating a higher bed utilization efficiency.

Structure and properties analysis of yttrium doped high-voltage LiNi0.5Mn1.5O4 cathode materials for Li-ion batteries

High voltage cathode spinel material of LiNi0.5Mn1.5O4 was doped by yttrium (Y) element in the form of LiNi0.5Mn1.5−x Y x O4 (x = 0, 0.05, 0.1) for Li-ion batteries. Structure and properties analysis was conducted to study the effect of Y addition on the crystal structure and the electrochemical performances of LiNi0.5Mn1.5−x Y x O4. The results show that undoped LiNi0.5-Mn1.5O4 (x = 0) fit to cubic spinel structure with space group Fd-3m with some LixNi1-xO detected as impurities. The addition of Y with x = 0.05 and 0.1 resulted in the change of LiNi0.5Mn1.5−x Y x O4 structure to space group P4 332. The Y addition was confirmed to enter 4b site co-existed with Mn and this result is closely related to the increase in lattice parameters a from 8.1384(1) Å to 8.1496(5) Å and 8.1627(1) for x = 0, 0.05 and 0.1, respectively. The cubic unit volume of LiNi0.5Mn1.5−x Y x O4 also increased with increasing Y addition. The addition of Y is liable to the formation of more stable [Mn,Y]O6 and MnO6 octahedra and whole crystal structure. The result from charge/discharge analysis shows that the addition of Y resulted in decreasing discharge capacity from 123.56 mAh g−1 to 105.175 mAh g−1 and 104.369 for x = 0.05 and 0.1, respectively. However, capacity retention after the 25th cycle increased constantly from 77% to 88% and 92% with increasing Y addition. Doped Y, in general, improves the electrochemical performance of LiNi0.5Mn1.5−x Y x O4 as cathode material for LIBs.

Classical density functional theory: The local density approximation

We prove that the lowest free energy of a classical interacting system at temperature [Formula: see text] with a prescribed density profile [Formula: see text] can be approximated by the local free energy [Formula: see text], provided that [Formula: see text] varies slowly over sufficiently large length scales. A quantitative error on the difference is provided in terms of the gradient of the density. Here [Formula: see text] is the free energy per unit volume of an infinite homogeneous gas of the corresponding uniform density. The proof uses quantitative Ruelle bounds (estimates on the local number of particles in a large system), which are derived in an appendix.

Energy Absorption and Damage Analysis of Fragments in High-Speed Impact on Composite Honeycomb Sandwich Structures

With the continuous innovation of UAV technology, composite honeycomb sandwich structures are used more and more in the fuselage structure of UAVs, and their anti-high-speed fragment impact performance has become a concern. In order to study the influence of fragments on the damage degree of composite honeycomb structures and analyze the damage difference of different initial velocity fragments on different composite honeycomb structures, based on the numerical simulation results of high-speed impact, the energy absorption characteristics of different honeycomb sandwich structures are analyzed, and the honeycomb structure with better energy absorption is selected for 24 impact experiments. The velocity range of fragment impact is 141–368 m/s. The typical damage of the upper core layer and the lower core layer in each structure is analyzed, and the energy absorption theory is used to compare the conditions of each group. The results show that ST-3-3 has the best energy absorption characteristics. Under different velocity impacts, the energy absorption per unit volume of the ST-3-3 structure reaches 521.6~659.6 × 103 J/m3, which is about 30.6% higher than that of the same design structure. The four groups of composite honeycomb sandwich structures designed in the experiment have obvious deformation in the process of impact, except that the deformation of the bottom skin of the ST-6-6-1 structure is not obvious, and the deformation of the other three groups is more obvious with the increase in structural resistance. This research shows that the reasonable arrangement of the structure and material of the composite honeycomb sandwich can better cope with the impact of high-speed fragments and reduce the damage to the structure.