Meridional Direction Research Articles

აჭარა-გურიის გეოლოგიური აგებულება მიღებული მაღლივი-კოსმოსური მასალების დეშიფრირებით

The geological structure of the Adjara-Guria region is defined by the fault zones of the orthgonal-diagonal system, which are the constituent parts (segments) of the transregional lineaments, and are well interpreted on high-space images.The block structure of the regionis determined by fault zones. Nine tectonic blocks of different configurations and geological structures are separated. There are deciphered 11 and 12 km wide tectonic zones with meridian direction, compiled,replaced by a large number of faults and related dykes. The gold occurencesin the region are associated with meridian structures, that’s why the identified tectonic zones are promising spaces for gold.

Thermal analysis of a reflection mirror by fluid and solid heat transfer method.

High-repetition-rate free-electron lasers impose stringent requirements on the thermal deformation of beamline optics. The Shanghai HIgh-repetition-rate XFEL aNd Extreme light facility (SHINE) experiences high average thermal power and demands wavefront preservation. To deeply study the thermal field of the first reflection mirror M1 at the FEL-II beamline of SHINE, thermal analysis under a photon energy of 400 eV was executed by fluid and solid heat transfer method. According to the thermal analysis results and the reference cooling water temperature of 30 °C, the temperature of the cooling water at the flow outlet is raised by 0.05 °C, and the wall temperature of the cooling tube increases by a maximum of 0.5 °C. The maximum temperature position of the footprint centerline in the meridian direction deviates away from the central position, and this asymmetrical temperature distribution will directly affect the thermal deformation of the mirror and indirectly affect the focus spot of the beam at the sample.

Analytical calculation approach for rocket nose cone structure with orthotropic material

The Authors of this research developed an analytical calculation method to estimate the strength of nose cone structures made of orthotropic materials, which were crucial components in aircraft and spacecraft. Strength analysis of nose cones had been comprehensively addressed for isotropic materials; however, the lack of efficient approaches for orthotropic materials presented a challenge. In this research, a new analytical method was proposed, combining membrane stress theory for isotropic materials with classical laminate theory for orthotropic materials. This approach enabled the determination of stresses on the nose cone shell structure in both meridional and circumferential directions in an efficient and straightforward manner. The analysis results indicated that the developed analytical method exhibited stress distribution trends similar to those obtained using the Finite Element Method. Stresses in the +45° and –45° direction, as well as in-plane shear stress and Tsai-Wu failure indices, showed trend similarity between the two methods. Despite specific numerical differences in the calculation results, these consistent trends suggested that the analytical method could serve as a tool for the preliminary design of a nose cone structure with a similar configuration analyzed in this study.

Nonlinear Finite Element Formulation for Thin-Walled Conical Shells

This study presents a novel finite element formulation to predict the geometrically nonlinear response of conical shells under a wide range of practical loading conditions. The formulation expresses the discretized equilibrium equations in terms of the first Piola-Kirchhoff stress tensor and its conjugate gradient of the virtual displacements, is based on the kinematics of Love-Kirchhoff thin shell theory and the Saint-Venant-Kirchhoff constitutive model, and captures the follower effect of pressure loading. The formulation takes advantage of the axisymmetric nature of the shell geometries by adopting a Fourier series to characterize the displacement distributions along the circumferential direction while using Hermitian interpolation along the meridional direction. Comparisons with general shell models show the accuracy of the formulation under various loading conditions with a minimal number of degrees of freedom, resulting in a significant computational efficiency compared to conventional general-purpose shell solutions.

Impacts of Local Circulations on Ozone Pollution in the New York Metropolitan Area: Evidence From Three Summers of Observations

AbstractElevated surface ozone levels are often detected in the New York metropolitan area during summertime. Moreover, surface ozone in this region exhibits sharp spatial gradients and distinctive diurnal cycles under the influence of complex boundary layer circulations induced by the intricate coastal geometry. This study examines how surface ozone is impacted by local circulations spatially and temporally under different temperature scenarios (all summer days, hot summer days, and extreme heat days) with the help of cluster‐based meteorological conditions during the summertime of 2017–2019. The most polluted days are found to be highly associated with hot sea breeze days with weak background flow. When sea breeze development in the New York Bight is delayed and its penetration north is intercepted by the dominant westerlies during hot summer days, daily maximum 8‐hr average ozone (DMA8) in some ozone hot spots of New York City (NYC) and the south shore of Connecticut (CT) typically drops 9–10 ppb under comparable temperature levels. The average regional decrease of DMA8 for NYC and coastal CT is 6.7 and 8.3 ppb, respectively. Furthermore, we conclude that a change in early morning meridional wind direction is the most critical meteorological characteristic in controlling sea breeze onset type and helping modulate ozone exceedances in the region during extreme hot days when ozone exceedances are expected to be very common. The conclusion is further demonstrated with two case studies during the Long Island Sound Tropospheric Ozone Study 2018 field campaign.

The aeroelastic stability characteristics of a ring-stiffened conical three-layered sandwich shell with an FG auxetic honeycomb core utilizing zig-zag shell theory

This paper is devoted to the supersonic flutter analysis of a ring-stiffened conical three-layered sandwich shell consisting of an auxetic honeycomb (AH) core fabricated from functionally graded material (FGM). The face sheets are manufactured of FGM as well in which the volume fraction of the ceramic increases from zero at the inner surface to one at the outer surface based on a power-law function. The sandwich shell is mathematically modeled based on the Murakami's zig-zag shell theory and the aerodynamic pressure is modeled utilizing piston theory. The derivation of governing equations along with compatibility and boundary conditions are performed using Hamilton's principle and are solved through a semi-analytical solution consisting of an exact solution in the circumferential direction followed by an approximate solution in the meridional direction. The flutter boundaries are attained to investigate the variations of the natural frequencies and damping ratios to find the critical aerodynamic pressure (CAP). The impacts of several factors on the CAP are examined such as the power-law index, geometric characteristics of the cells in the FGAH, thickness of the honeycomb core, location of the ring, and boundary conditions. It is observed that an optimal location can be found for the ring support somewhere between the middle length and large radius of a conical shell that provides the best aeroelastic stability.

Discrete differential geometry-based model for nonlinear analysis of axisymmetric shells

In this paper, we propose a novel one-dimensional (1D) discrete differential geometry (DDG)-based numerical method for geometrically nonlinear mechanics analysis (e.g., buckling and snapping) of axisymmetric shell structures. Our numerical model leverages differential geometry principles to accurately capture the complex nonlinear deformation patterns exhibited by axisymmetric shells. By discretizing the axisymmetric shell into interconnected 1D elements along the meridional direction, the in-plane stretching and out-of-bending potentials are formulated based on the geometric principles of 1D nodes and edges under the Kirchhoff–Love hypothesis, and elastic force vector and associated Hessian matrix required by equations of motion are later derived based on symbolic calculation. Through extensive validation with available theoretical solutions and finite element method (FEM) simulations in literature, our model demonstrates high accuracy in predicting the nonlinear behavior of axisymmetric shells. Importantly, compared to the classical theoretical model and three-dimensional (3D) FEM simulation, our model is highly computationally efficient, making it suitable for large-scale real-time simulations of nonlinear problems of shell structures such as instability and snap-through phenomena. Moreover, our framework can easily incorporate complex loading conditions, e.g., boundary nonlinear contact and multi-physics actuation, which play an essential role in the use of engineering applications, such as soft robots and flexible devices. This study demonstrates that the simplicity and effectiveness of the 1D discrete differential geometry-based approach render it a powerful tool for engineers and researchers interested in nonlinear mechanics analysis of axisymmetric shells, with potential applications in various engineering fields.

Thermal optimization of a high heat load liquid-metal-bath cooled mirror at the Hefei Advanced Light Facility.

Within the beamlines of diffraction-limited storage rings, the liquid-metal-bath cooling scheme is a prevalent choice for the cooling of high-heat load mirrors. This study employs the finite element analysis method to evaluate the thermal deformations of liquid-metal-bath horizontally deflecting mirrors in the Hefei Advanced Light Facility. In particular, we introduce a novel optimization strategy to obtain the optimal thermal deformation scenario, which also satisfies mechanical design requirements. Moreover, a concurrent optimization approach across multiple structural parameters of mirrors is adopted to attain globally optimal thermal deformation. Following the optimization of the mirror's structural parameters, the curvature radius increases to 227 km, while the residual slope error decreases to 36.3 nrad at 6eV in the meridian direction. The ray tracing analysis of the beam demonstrates a considerable reduction in the influence of thermal deformation on the beam's focal point. This work proposes an optimization method for designing cooling schemes under mechanical constraints.

Diversity of the tropical easterly jet’s core location

The upper-tropospheric tropical easterly jet (TEJ) is one of the most important systems in modulating the Asian summer monsoon rainfall. In addition to the intensity variability that has been extensively studied, the TEJ’s core experiences remarkable changes in the zonal and meridional directions. The TEJ can be identified as three locational patterns using the cluster analysis: the east, northwest, and southwest modes. The frequencies of the three locational modes exhibit discernable changes on the monthly and the interannual-decadal time scales. While the anomalous zonal divergent circulation with the convergent/divergent center over the tropical Indian Ocean (IO) determines the zonal location of the TEJ’s core, the meridional temperature gradient between the Eurasian continent and the tropical IO distinguishes the meridional location of the TEJ’s core. It reflects the fundamental role of the large-scale east-west and north-south thermal contrasts in the movement of the TEJ’s core location. The variability of the TEJ’s core location has distinct impacts on the summer monsoon precipitation via redistributing the upper-level divergence and modulating the monsoon meridional circulation, especially in South, Southeast, and East Asia. In conjunction with the thermal effect of the Tibetan Plateau, the meridional shift of the TEJ’s core can affect the precipitation along the south slope of the Tibetan Plateau. These findings highlight the cause of the diversified TEJ’s core location and the significant impacts on the summer monsoon rainfall.

Deformation behavior and failure mechanism of AA7075 alloy during the cryogenic temperature-assisted incremental sheet forming process

High-strength aluminum alloys are potential structural materials for thin-walled aerospace and automotive components. However, the limited formability at room temperature (RT) hinders their wide industrial application. In this study, a cryogenic temperature-assisted incremental sheet forming (CT-ISF) process for manufacturing 3D curved thin-walled structures was proposed. An experimental platform for CT-ISF was established to form AA7075 alloys. We found that the formability of the solution-treated AA7075 alloy sheet was greatly improved under the cryogenic environment without sacrificing its strength. In combination with double pass forming process, the formability of the sheet can be further improved. The stable deformation of the sheet is promoted due to the suppression of the Portevin-Le Chatelier (PLC) effect at CT, which reduces axial force fluctuations during the forming process. The line roughness value of the meridional direction was reduced by 36.8% at CT due to the enhanced work-hardening and the utilization of MoS2 lubricant. In terms of microstructural evolution, we found that the fracture morphology of the formed parts changed from tensile fracture at RT to shear fracture at CT. The improved formability was attributed to increased Goss and E texture contents, delay in dislocation evolution, and suppression of the PLC effect. This work introduces a novel CT-ISF process that significantly enhances the formability of high-strength Al alloy. In particular, it unravels the enhancement mechanism of formability in the CT-ISF process, providing theoretical support for further research.

Statistical evaluation of measured biomechanical properties of human brain aneurysm samples.

<p>Human brain aneurysms may often prove fatal if not re&shy;cognized in time and treated accordingly. The understanding of development and rupture of aneurysms can significantly be improved by the application of numerical modelling, which in turn, requires the knowledge of mechanical properties of vessel wall. This study aims to identify assumed differences with respect to age, sex, spatial orientation, and rupture by utilizing detailed statistical analysis of uniaxial tensile measurements of human brain aneurysm samples, performed by the authors in a previous project.</p>. <p>At surgery of 42 patients, aneu&shy;rysm fundi were cut distally to the clip. In each case, depending on size, varying number of stripes (altogether 88) were prepared and uniaxial stress-strain measurements were performed. Quantities related to the capacity, energy absorption or stiffness were determined and statistically analysed.</p>. <p>The number of specimens in the aneurysm sample was sufficient to establish statistical differences with respect to sex and rupture (p&lt;0.05). No significant differences were detected in orientation, though higher values of stresses and deformations were ob&shy;tained in the circumferential direction com&shy;pared to the meridional direction.&nbsp;</p>. <p>Significant differences bet&shy;ween sexes with respect to ultimate deformations were demonstrated according to expectation, and the hypothesis on equality of energy capacity could be supported. Similarity of curves with respect to specimen orientation was also observed and ruptured aneurysm sacs tended to be smaller in size. It seems that differences and trends described in this paper are realistic and need to be applied in numerical modelling.</p>.

Effect of pulsation elongational stress on the structure and properties of preparing self-reinforced sheets

A vane-type melt pulsation pumping device induces molecular chain orientation in HDPE melts via pulsating stretch-compression, enabling self-reinforced sheet extrusion. Experiments assess the impact of varying device temperature and rotational speed on the mechanical properties and microstructure of extruded sheets. The results show that the orientation of the samples can be preliminarily verified by heating test. SEM analysis reveals closely aligned HDPE crystal regions along the extrusion direction following pulsating elongational stress. 2D-WAXD analysis demonstrates a shift in diffraction intensity where it diminishes in the meridional direction and intensifies in the equatorial plane, resulting in a maximum orientation index of 0.683, an increase of 16.6% compared to direct extrusion. When the temperature of the melt pulsation pumping device is set to 180°C and the shaft speed is set to 30 rpm, the tensile strength of the sheets in the extrusion direction reached a maximum value of 66.37 MPa, surpassing that of directly extruded samples by 42.7% and that of compression-molded samples by 90%. In summary, this research realizes the self-reinforced and efficient continuous extrusion of single-component HDPE sheets through a simple device and process, which is of great significance for convenient recycling and environmental protection.

Free vibration analysis of a sandwich conical shell with a magnetorheological elastomer core, enriched with carbone nanotubes and functionally graded porous face layers

In this paper, the free vibration behaviors of a sandwich conical shell with a magnetorheological elastomer (MRE) core enriched with carbon nanotubes (CNTs) and two functionally graded (FG) porous face layers are investigated. The mathematical modeling of the shell is performed via the first-order shear deformation theory (FSDT) incorporating the continuity conditions between the face layers and the core. The porosity parameters are adjusted to provide the same mass for all porosity dispersion patterns. The governing equations and boundary conditions are derived via Hamilton’s principle and are solved through a semi-analytical solution to attain the natural frequencies and the loss factors for various boundary conditions. First, appropriate triangular functions are utilized to provide an exact solution in the circumferential direction. Then, a numerical solution is presented in the meridional direction utilizing the differential quadrature method (DQM). The influences of various factors on the natural frequencies and loss factors are investigated including intensity of the applied magnetic field, mass fraction of the CNTs subjoined to the core, thickness of the CNT-reinforced MRE core, thickness of the FG porous face layers, porosity parameter and dispersion pattern of the pores in the FG porous face layers, and the boundary conditions. Numerical results show that although subjoining CNTs to the MRE core and applying magnetic field have weak effects on the natural frequencies of the shell, increases in the mass fraction of the CNTs and intensity of the applied magnetic field result in remarkable increases in the loss factors, and provide stronger vibration suppression.

Functionally graded structures in the involucre of Job’s tears

Nature is filled with materials that are both strong and light, such as bones, teeth, bamboo, seashells, arthropod exoskeletons, and nut shells. The insights gained from analyzing the changing chemical compositions and structural characteristics, as well as the mechanical properties of these materials, have been applied in developing innovative, durable, and lightweight materials like those used for impact absorption. This research concentrates on the involucres of Job’s tears (Coix lacryma-jobi var. lacryma-jobi), which are rich in silica, hard, and serve to encase the seeds. The chemical composition and structural characteristics of involucres were observed using scanning electron microscopy and energy-dispersive x-ray spectroscopy and optical microscopy with safranin staining. The hardness of the outer and inner surfaces of the involucre was measured using the micro-Vickers hardness test, and the Young’s modulus of the involucre’s cross-section was measured using nanoindentation. Additionally, the breaking behavior of involucres was measured through compression test and three-point bending tests. The results revealed a smooth transition in chemical composition, as well as in the orientation and dimensions of the tissues from the outer to the inner layers of involucres. Furthermore, it was estimated that the spatial gradient of the Young’s modulus is due to the gradient of silica deposition. By distributing the hard, brittle silica in the outer layer and elastoplastic organic components in the middle and inner layers, the involucres effectively respond to compressive and tensile stresses that occur when loads are applied to the outside of the involucre. Furthermore, the involucres are reinforced in both meridional and equatorial directions by robust fibrovascular bundles, fibrous bundles, and the inner layer’s sclerenchyma fibers. From these factors, it was found that involucres exhibit high toughness against loads from outside, making it less prone to cracking.

The Variations of Gravity Wave Activities During the Formation of the Large Horizontal Wind Shears in the Static State Lower Thermosphere

AbstractLarge horizontal winds and shears across the mesopause region have been observed by sounding rockets and satellites but with limited simultaneous temperature profiles to date. This feature is critical to the diagnosis of the insitu dynamic conditions. Theories suggest this feature may be related to variations of the atmosphere static stability, Brunt‐Väisälä frequency square (N2), and the wave activity in the mesosphere and lower thermosphere (MLT) that cannot be resolved by the models. Since 2020, the Na Doppler lidar at Utah State University has attained several hundred hours of wind and temperature profiles in the MLT up to ∼110 km altitude. This paper focuses on the variations of these large winds and shears (&gt;40 m/s/km), along with their potential relation to the activities of the various scales of gravity waves in the static state upper mesosphere, measured coordinately by the Advanced Mesospheric Temperature Mapper operating alongside the lidar. The investigation reveals that larger shears tend to occur in the meridional direction than the zonal direction and are observed more frequently in winter. The shears are comparable in both directions in summer and more large shears were observed in zonal direction. In addition, small shears occur when the medium‐scale waves are completely or partially blocked by the mean wind, though no convincing evidence relates small‐scale wave activities with these large winds and shears. Furthermore, small and decreasing N2 in the upper mesopause region are associated with insignificant magnitude of the shears.

Short-term forecasting method for prevailing orientation of leads in the Laptev Sea ice cover during winter-spring season

Sea ice leads are potential routes of easier navigation in the Arctic seas during winter-spring season. Forecasts of the prevailing orientation of ice leads are required for the early selection of the optimal route of a ship in ice. An automated method for short-term forecasting of the prevailing orientation of leads in the Laptev Sea is developed in AARI based on the analog method. Data sources for making a forecast include predictive fields of atmospheric pressure up to 3 days in advance and historical data on surface atmospheric pressure, ice drift and sea ice leads. The data on ice leads are obtained by interpreting SuomiNPP satellite images in a visible and infrared range at 375 m spatial resolution for the cold seasons 2016–2022. The ice drift data are freely available OSI SAF data. In order to make a forecast of the prevailing orientation of leads by a predictive atmospheric pressure field, it is necessary to select from an electronic data archive a historical field of atmospheric pressure that is the most similar to the predictive field. The lead characteristics on the selected date are taken as the predictive ones. Automated selection of an analog consists in searching for an atmospheric pressure field from the electronic data archive which has minimal metrics for the forecast date together with 2 previous days. The metric is calculated as the sum of the squared differences between the change in atmospheric pressure per 1 km in the latitudinal and meridional directions between the predictive atmospheric pressure field and the potential analog field. Actual lead data for a date of the selected analog may not be available due to thick clouds. In this case, the direction of the minor axis of the strain ellipse calculated from ice drift data is taken as the prevailing orientation of leads. The success ratio of diagnostic forecasts by the method developed is 72 %. Comparison of the success ratio of the diagnostic forecasts with the results of inertial and climatic forecasts demonstrates a high effectiveness of the method for cases of abrupt change in the direction of air flows over the Laptev Sea within the first 1–2 days.

STRUCTURAL POSITION AND DISTRIBUTION OF THE LOWER CRETACEOUS BLACK SHALE DEPOSITS WITHIN THE SILESIAN NAPPE OF THE UKRAINIAN CARPATHIANS

The article presents the results of studying the structural position and distribution of potentially oil-generating, organic-enriched Lower Cretaceous black shale deposits of the Shypot Formation, developed within the Silesian Nappe, using the methods of geological mapping and structural analysis. We concluded, that these deposits, which are exposed in the Vicha River basin near the town of Volovets among a continuous field of Oligocene flysch, are the part of the stratigraphic succession of the Silesian Nappe, and they are not a large olistolith or an allochthonous tectonic remnant of another, more internal nappe. Shypot Formation fills a large (1 × 3 km) subvertical tectonic lens. The rocks of the Shypot Formation are represented here by medium-rhythmic flysch: sandstone beds alternating with dark gray and black foliated mudstone (black shale) layers. They are lithified products of both medium-density turbidite flows and hemipelagic deposition of clayey material with a significant amount of organic matter. In the contact zone of the tectonic lens with the surrounding rocks, the deposits are intensively deformed, almost isoclinal folds with subvetrical hinges are observed, which suggest the strike-slip movements. A tectonic mélange is recorded here, which is represented by small blocks (clastolites) of brittle sandstones, sometimes similar to Shypot sandstones, placed in a silt-pelitic ductile matrix. Foliation of the mélange matrix is also subvertical and close to the meridional and/or subcarpathian direction. The structural studies carried out show that in the zone of this contact there were compressive stresses perpendicular to the Carpathian orogen, and stress fields that caused strike-slip movements, most likely right-lateral along the Carpathian thrusts. The tectonic lens is located within the broad Latorytsa-Stryi shear zone, and probably extruded out from deep horizons by transpressive movements (compression and strike-slip) and forms a “positive flower structure”. The vertical foliation in the mélange suggests that small blocks of Shypot sandstones were extruded up together with the ductile mélange matrix during diapirism. Similar processes probably led to the rise of a large lens of Shypot sandstones as the positive flower structure. The studies suggests that the black shale deposits of the Shypot Formation, enriched with organic matter, are widespread at some depth within the Silesian Nappe, and in some places are pushed up to the level of the Oligocene flysch. As a result, the Shypot Formation and Oligocene flysch are now in direct contact along faults/mélange zones. The presence of Lower Cretaceous potentially oil- and gas-generating black shale deposits within the Silesian Nappe significantly increases the prospects for oil and gas exploration in this area.

Free vibrational behavior of a conical sandwich shell with a functionally graded auxetic honeycomb core

In the presented paper, the free vibration of a conical sandwich shell with a re-entrant auxetic honeycomb (AH) core made of ceramic-metal functionally graded material (FGM) is analyzed. The percentage (volume fraction) of ceramic in the functionally graded auxetic honeycomb (FGAH) core changes from zero at the inner surface of the core to one at the outer surface according to a power-law function. The FGAH core is enfolded with a homogenous outer face layer made of ceramic and a homogenous inner one made of metal. The shell is modeled based on the first-order shear deformation theory (FSDT), and Hamilton’s principle is utilized to attain the governing equations and boundary conditions. A trigonometric-based analytical solution is carried out in the circumferential direction, and an approximate solution is presented in the meridional direction via the differential quadrature method (DQM). The impacts of various factors on the natural frequencies are inspected like the thickness of the core-to-thickness of the shell ratio, geometric factors of the cells in the FGAH core, and material gradation in the FGAH core.

Influence of temperature perturbation on moisture dynamics

We analyzed the perturbation effect of temperature on the moisture content in the atmosphere [], considering the saturation phenomenon. The air parcels of a saturated atmosphere are made of dry air, vapor, cloud, and rain water that flow on a rotating Earth, with a temperature perturbations induced at 9°1′48″ N, 38°44′24″E and 6.324 km above the Earth’s surface. The fundamental atmospheric parameter of this saturated moist air was treated as temperature-dependent, and the pressure force exerted on it by the precipitation and cloud water is not considered in the numerical computation. In this proposed research, the initial value of wind speed along zonal, meridional, and vertical directions varies with elevation, and the interaction of the atmosphere with the Earth’s surface is not neglected. The result of the investigation revealed that a single tropospheric disturbance of an atmospheric variable is a major factor in the spread of different long period waves patterns (350 hours) and this atmospheric oscillations play a crucial role in transferring energy, momentum, and mass across different parts of the atmosphere, impacting global climate systems.

Effects of non-uniformity in thickness and volume fraction of agglomerated CNTs on the dynamics of a spinning CNT-reinforced nanocomposite truncated conical shell

In the presented work, the free vibration analysis of a rotating truncated conical shell whose thickness varies in the meridional direction is examined. The material that the shell is made of is a polymeric matrix (epoxy) enriched with carbon nanotubes (CNTs) whose volume fraction varies in the meridional direction. CNTs agglomeration is considered and the density and elastic constants of such a two-phase nanocomposite are calculated sequentially based on the Eshelby–Mori–Tanaka approach alongside the rule of mixture. The conical shell is modeled using the first-order shear deformation theory (FSDT) including the relative acceleration, Coriolis acceleration, and centrifugal acceleration along with the initial hoop tension, and the governing equations are obtained utilizing Hamilton’s principle. The solution of governing equations is performed via the combination of an analytical solution in the circumferential direction and a numerical one in the meridional direction via the differential quadrature method (DQM). The impacts of several parameters on the forward and backward natural frequencies of such a rotating shell are studied such as chirality, mass fraction and dispersion pattern of the CNTs, thickness variation parameters, and boundary conditions. It is observed that higher natural frequencies and critical rotational speeds can be achieved for CNT-reinforced conical shells when the volume fraction of the CNTs and the thickness of the shell increase from its small radius to the large one.