Cone-shaped Body Research Articles

Non-uniform heat source or sink on the radiated and thermophoretic flow of slender body of paraboloid and cone revolutions in a saturated medium with Brownian motion

Heat and mass transfer acquired the attention of investigators and experts because of massive uses in the field of medicine, manufacturing of modern aircrafts, uses in advanced water filtration plants, distillation process of water, more efficient electronic instruments, more efficient batteries, textile industry, uses as manufacturer in cosmetics industry and modern defense equipment. By viewing this, we considered the numerical study of Fourier flux and buoyancy driven forces on the flow of thermal and diffusion transmission of body revolutions (Paraboloid and cone), situated in a water-logged Darcy medium by allowing the radiation, Brownian motion, time-space dependent heat source or sink, and thermopheretic. Later on, the governing system is solved via Runge–Kutta method. Properties of convoluted governing measures of the organisms on local Nusselt and Sherwood numbers along with velocity, thermal and diffusion shapes are described with the aid of graphically and tabular form. It is stimulating to declare that the non-uniform heat source or sink is highly dominated in cone form of revolution as associated to paraboloid form of flow due to more distribution of mass transfer. From this, one can draw the conclusion that wherever there are higher mass transportation phenomena, cone-shaped body of revolution can be used. It is found that the time- and space-dependent heat source or sink performs as a regulating factor of the transmission of flow phenomena.

Theoretical analysis of convective transport over a slender body of revolution

The study of thermal transport in the laminar boundary layer had been a great area of research since long ago because of its practical necessity in different fields of engineering such as aerodynamics, electronics cooling, designing of turbine blades, etc. The primary goal of the research has always been to look into geometries or shapes that have higher heat transfer rates but a less viscous drag. This is also a topic of fundamental interest to the aerospace industry. For this purpose, a cone-shaped body of revolution has been considered. Such geometries are chosen due to their wider acceptance in modern aerodynamics, with their enhanced heat transfer rates and lower aerodynamic drag. In this connection, axisymmetric bodies of revolution having different body contours and involving surface transverse curvature are usually considered. The selection of such a curved body and the imposed particular type of momentum and thermal boundary conditions make the problem of non-similar nature. Such kinds of problems are normally dealt with by an implicit finite difference scheme due to the accuracy of the solution. The current problem has also been solved with the same numerical scheme. It is concluded that a more streamlined body of revolution has a less spread of velocity and temperature within the boundary layer with a large heat transfer rate and wall skin-friction. On the other hand, the parabolic body of revolution has a large distribution of velocity and temperature but less heat transfer rate and wall skin-friction. Moreover, the assisting role of surface transverse curvature on temperature distribution and wall skin-friction has also been observed in this study.

Aero-Thermal Analysis of Rarefied Flow Over Inverse Cone Shaped Objects Using Direct Simulation Monte Carlo Analysis

Abstract When an object undergoes atmospheric entry, it experiences drag and heat load over its surface which determines its trajectory and ability to survive the hostile flow conditions. This work performs numerical analysis using direct simulation Monte Carlo (DSMC) simulations to study key flow features and properties on a cone-shaped body. The cone is created by varying the angle of extrusion (α) of the flat-nosed face of a cylinder in positive and negative directions. Detailed analysis of the key flow features is conducted, and the results of the distribution of surface heat transfer and drag coefficient on each of the negative α are contrasted against the results obtained for zero and positive α for which compressible flow physics are well defined. For α≤45 deg, heat flux increases with an increase in α, while the total drag experienced by the body decreases. Meanwhile, when α is increased in the negative direction, an inverse cone is formed, which creates a cavity inside the body, and the body decelerates more with an increasing magnitude of α. In contrast, the wall heat flux inside the cone remains quite low. These conditions allow the body to maintain a significantly low temperature during high-speed flow, like in the case of planetary entry, in comparison with the high temperature resulting in α≤0 deg cases. The present study also helps to improve the understanding of optimum cone-shaped space objects from the perspective of drag and heat flux.

Theoretical Investigations on Slamming of Cone-Shaped Bodies

A general expression for the pressure distribution on a cone penetrating the water surface is derived from the similar procedure developed by Wagner for a wedge. The effect of trapped air between the falling body and the water is ignored for this investigation. The pressure distributions, velocity potentials, stream functions, and piled-up water phenomenon are summarized and compared with those for the wedge. Wagner provided a theoretical analysis on the slamming of a wedge [1,2,3].3 His approach was to approximate the wedge as an equivalent flat plate provided that the wedge had a small deadrise angle. By means of the velocity potential technique and the Bernoulli equation, he derived equations for determining the pressure distributions on the impact surface of the wedge. A cone piercing the water surface has been studied experimentally by Watanabe [4] and theoretically by Shiffman and Spencer [5]. However, their work provided only the total force acting on the impact surface of a cone. The purpose of the present work is therefore to determine theoretically the slamming pressure distribution of a cone. The similar approaches developed by Wagner for his wedge equations are used for this investigation.

3-D Geological Mapping of Rocks Potentially Suitable for Capturing Carbon Dioxide from the Atmosphere

Rapid increase of the Anthropocene ambient air CO2 concentration value is the main cause of the 1.2 o C global temperature rise creating the recent adverse climate and weather changes. Promising new methods to capture CO2 from the air are being developed but remain too expensive for worldwide applications. Mantle-derived rocks, primarily basalts, peridotites and serpentinites are likely to play an important role in future CO2 reduction because of relatively rapid disintegration of minerals (including olivine and serpentine) in these rocks potentially resulting in widespread CO2 capture. Examples to be discussed include artificially enhanced carbonization of water emitted from ophiolites, and acid dissolution of serpentinites resulting in indirect mineral carbonation by optimizing temperature and pressure conditions. Reconstruction of a large cone-shaped body of serpentinite situated within the Mount Albert peridotite intrusion in Québec is presented as an example of the rôle 3-D geologic mapping can play in future CO2 reduction efforts.

Entropy generation estimation in pseudoplastic and dilatant fluid flows over a vertical plate and frustum of a cone

This paper aims to analyse mixed convective flow of Ostwald-de Waele power-law fluid flow past vertical plate and frustum of a cone in a non-Darcy (Forchheimer) porous medium with thermal dispersion and viscous dissipation and the main focus is to estimate entropy generation in the medium. A local non-similarity solution technique with spectral local linearisation procedure is incorporated to deal with governing equations and boundary conditions. It is noticed that the maximum value of Bejan number is obtained for (i.e. forced convection) and with increment in viscous dissipation parameter, it is decreased effectively. This problem has a broad range of applications such as in polymer industry, processing of edible items or slurries at industrial level due to involvement of cone-shaped bodies in these areas. The entropy generation expression has been derived for this fluid flow model for the first time and then analysed the entropy generation and Bejan number in detail.

Axial Uplift Behaviour of Belled Piers in Coarse-Grained Saline Soils

Bearing capacity of belled pier foundation is critical in designing transmission lines in coarse saline soil region. This paper describes model test results on belled pier foundations. Axial uplift behaviours including failure modes, load-displacement curves, and ultimate uplift bearing capacity were discussed. The failure planes in four cases were obtained from pulled out cone-shaped bodies. An empirical equation was developed with a critical parameter of an uplift angle in design. Results indicate the range where the ground uplift shows circular extension at higher loads and the overall shear failure finally occurred. The load-displacement curves are primarily softening, and the uplift bearing capacity for coarse-grained saline soils (CSS) in the crystalline state increases at larger thickness, higher than that in dissolved state. Failure planes all exhibit approximately linear change from bottom to up. The angles of uplift for soils in crystalline and dissolved states can be taken as 34° and 18°, while 32° for the conventional for the sake of safety. Uplift behaviour of belled piers in CSS was modelled incorporating a practical interface model, with both failure planes and plastic range.

The flank wear prediction in micro-milling Inconel 718

PurposeCutting tool wear is known to affect tool life, surface quality, cutting forces and production time. Micro-milling of difficult-to-cut materials like Inconel 718 leads to significant flank wear on the cutting tool. To ensure the respect of final part specifications and to study cutting forces and tool catastrophic failure, flank wear (VB) has to be controlled. This paper aims to achieve flank wear prediction during micro-milling process, which fills the void of the commercial finite element software.Design/methodology/approachBased on tool geometry structure and DEFORM finite element simulation, flank wear of the micro tool during micro-milling process is obtained. Finally, experiments of micro-milling Inconel 718 validate the accuracy of the proposed method for predicting flank wear of the micro tool during micro-milling Inconel 718.FindingsA new prediction method for flank wear of the micro tool during micro-milling Inconel 718 based on the assumption that the wear volume can be assumed as a cone-shaped body is proposed. Compared with the existing experiment techniques for predicting tool wear during micro-milling process, the proposed method is simple to operate and is cost-effective. The existing finite element investigations on micro tool wear prediction mainly focus on micro tool axial wear depth, which affects size accuracy of machined workpiece seriously.Originality/valueThe research can provide significant knowledge on the usage of finite element method in predicting tool wear condition during micro-milling process. In addition, the method presented in this paper can provide support for studying the effect of tool flank wear on cutting forces during micro-milling process.

The structure of the Lomonosov volcanic pipe in the Arkhangel’sk diamond province from anomalies of the microseismic field

This paper presents results from a study of the Lomonosov volcanic pipe as derived from anomalies of the microseismic field. Microseismic sounding revealed that this volcanic pipe is a cone-shaped body with a small gradient of microseismic intensity motion (2 to 5 dB). Discontinuities generally show greater contrasts compared with the variations of microseismic motion in the pipe body. Comparison of the results of this microseismic sounding with other geological and geophysical data showed that the intensities of the microseismic field along lines that traversed the pipe reflect realistic structures of a kimberlite pipe and the host rocks. The method of microseismic sounding was used to reconstruct the deeper structure of the volcanic pipe and the host rocks down to depths greater than 2 km. We estimated the velocity contrast and the errors involved in the identification of vertical boundaries of the pipe. The volcanic pipe has a shape that is consistent with a nearly vertical source situated at a depth of a few hundred meters. This is hypothesized to be a typical occurrence for other diamond-bearing pipes as well.

Ejecta evolution during cone impact

AbstractWe present findings from an experimental investigation into the impact of solid cone-shaped bodies onto liquid pools. Using a variety of cone angles and liquid physical properties, we show that the ejecta formed during the impact exhibits self-similarity for all impact speeds for very low surface tension liquids, whilst for high-surface tension liquids similarity is only achieved at high impact speeds. We find that the ejecta tip can detach from the cone and that this phenomenon can be attributed to the air entrainment phenomenon. We analyse of a range of cone angles, including some ogive cones, and impact speeds in terms of the spatiotemporal evolution of the ejecta tip. Using superhydrophobic cones, we also examine the entry of cones which entrain an air layer.

Gas seeps in the North Caspian water area

Seismoacoustic profiling and sonar survey of the North Caspian water area revealed in some areas signs of intense release of methane from the sedimentary sequence. This fact was also supported by submarine videorecording data. Such sites are characterized by hummocky and ridgy morphologies, which accommodate local cone-shaped bodies (up to 1.3–1.5 m high) overgrown with algae, Balanus, and shelly material. Based on dredging data, these rises are composed of hard sandstones and shells. They can cover the seafloor or make up separate interlayers in the bottom sediments down to a depth of 2.7 m. Mineralogical studies demonstrated that the coarse-grained sediments are cemented with Mg-calcite, with δ13C reaching −32.6‰. They also include microcrystalline barite and globular iron sulfides. The results of investigation suggest that the local activation of authigenic mineral formation is related to gas discharge sources.

Geophysical modelling of the Ebersbrunn diatreme, western Saxony, Germany

ABSTRACTThe Ebersbrunn diatreme near Ebersbrunn, western Saxony, Germany, causes an elliptical Bouguer anomaly of about –2.5 m Gal, which covers an area of approximately 2.2 km × 2 km and an elliptical magnetic anomaly with values between –250 nT and 1000 nT about half a kilometre smaller in diameter and situated within the southern part of the Bouguer anomaly. Considering magnetic susceptibility and density values determined from core samples of the diatreme, a symmetrical, cone‐shaped body with an oval surface outcrop of 2 km × 1.5 km and a dip angle of the slopes of about 82° is modelled. It comprises a central structure with a diameter of 800–900 m and susceptibility values up to 9000*10−6 SI higher and densities up to 220 kg/m3 lower than the surrounding chimney. Additionally, susceptibility within the body increases with depth and decreases with the degree of weathering. The geometry can clearly be associated with the diatreme of a maar‐diatreme‐volcano. Regarding the petrographic information (the occurrence of pelletal lapilli as juvenile phase, the basaltoid character of the occurring ground mass of magmatic origin and 80% wall rock content) and the final geophysical model, the Ebersbrunn structure can definitely be regarded as the partially eroded remnant (diatreme and root zone) of a maar‐diatreme‐volcano. The association of earthquake swarms in intraplate regions of intersecting fractures and volcanism has led to renewed interest in the eroded maar‐diatreme‐volcano.

Rapid injection of particles and gas into non-fluidized granular material, and some volcanological implications

In diatremes and other volcanic vents, steep bodies of volcaniclastic material having differing properties (particle size distribution, proportion of lithic fragments, etc.) from those of the surrounding vent-filling volcaniclastic material are often found. It has been proposed that cylindrical or cone-shaped bodies result from the passage of “debris jets” generated after phreatomagmatic explosions or other discrete subterranean bursts. To learn more about such phenomena, we model experimentally the injection of gas-particulate dispersions through other particles. Analogue materials (glass beads or sand) and a finite amount of compressed air are used in the laboratory. The gas is made available by rapidly opening a valve—therefore the injection of gas and coloured particles into a granular host is a brief (<1 s), discrete event, comparable to what occurs in nature following subterranean explosions. The injection assumes a bubble shape while expanding and propagating upwards. In reaction, the upper part of the clastic host moves upward and outward above the ‘bubble’, forming a ‘dome’. The doming effect is much more pronounced for shallow injection depths (thin hosts), with dome angles reaching more than 45°. Significant surface doming is also observed for some full-scale subterranean blasts (e.g. buried nuclear explosions), so it is not an artefact of our setup. What happens next in the experiments depends on the depth of injection and the nature of the host material. With shallow injection into a permeable host (glass beads), the compressed air in the “bubble’ is able to diffuse rapidly through the roof. Meanwhile the coloured beads sediment into the transient cavity, which is also closing laterally because of inward-directed granular flow of the host. Depending on the initial gas pressure in the reservoir, the two-phase flow can “erupt” or not; non-erupting injections produce cylindrical bodies of coloured beads whereas erupting runs produce flaring upward or conical deposits. Changing the particle size of the host glass beads does not have a large effect under the size range investigated (100–200 to 300–400 μm). Doubling the host thickness (injection depth) requires a doubling of the initial gas pressure to produce similar phenomena. Such injections—whether erupting or wholly subterranean—provide a compelling explanation for the origin and characteristics of multiple cross-cutting bodies that have been documented for diatreme and other vent deposits.

Laminar free convection flow over a cone embedded in a stratified medium

Free convection flows which arise in a thermally stratified medium are of practical importance. Interest lies in the effect of stratification on temperature and velocity fields that arise in the flow and the consequent heat transfer from a heated body. In many engineering applications coneshaped bodies are often used. Free convection flow over a vertical cone has been studied by Hering and Crosh [I], Hering [2], Lin and Chao [3], Lin [4,] Alamgir [5] and recently by Watanabe [6]. A literature review reveals that the free convection flow over a vertical cone immersed in a stratified medium has not been studied so far. This has motivated us to carry out the present analysis. Laminar free convection flows over bodies of different shapes like vertical plate, sphere and cylinder in a stratified medium have been studied by various investigators; see, for example, Chen and Eichhorn [7-8].

Shock-free conical compression and expansion of a gas

Solutions of two-dimensional unsteady self-similar problems of the unlimited shock-free compression and expansion of an ideal gas into a vacuum when the gas is at rest at the initial instant of time inside a prism and cone-shaped bodies at constant density and pressure are constructed. The flow fields are partially constructed using classes of accurate solutions of the non-linear equation for the velocity potential, and partially by numerical calculations, in particular, by the method of characteristics. The features of the formulation of the boundary-value problems for conical unsteady flows are investigated. Approximate laws of the control of the motion of compressing pistons are constructed analytically. The degrees of cumulation of energy and density are obtained and it is shown that the non-uniform compression processes described are more favourable energy-wise than the process of spherical compression for obtaining local superhigh densities of a material. The flow fronts with points of discontinuity are constructed for problems of flow into a vacuum from a cone.

Two-dimensional Water Impact of Unsymmetrical Bodies

This paper presents a method for predicting the slamming pressure distribution over the ship surface of the two-dimensional arbitrary shape. The method is derived from the similar procedure developed by V. H. Wagner for a symmetric wedge penetrating the water surface, using the expanding flat plate approximation. The proposed method takes account of the piled up water at the free surface near the impinging body which is relevant to the pressure distribution and the peak value. For practical purposes, simple formulas are developed to estimate the maximum peak pressure on the surface of unsymmetrical wedges.Equations for the slamming of cone-shaped bodies are also shown in the appendix which are a little different from those derived by S. L. Chuang.

Plastic flow of cone-shaped bodies

Flows of an ideal rigidly-plastic incompressible medium, in the shape of a cone-shaped body, are considered for different external effects. The problem of axisymmetric flow reduces to a system of two ordinary differential equations whose solutions describe the limit state of conical tubes subjected to uniformly distributed annular tangential forces, normal and annular tangential forces, normal and longitudinal tangential forces on the inner and outer surfaces. The combined bending and tension of a conical sheet and the flow of plastic mass between two-dimensionally rough conical surfaces which are approaching exponentially in the annular coordinate are investigated.

End-expiratory volume in the rat: effects of consciousness and body position.

Functional residual capacity (FRC), tidal volume (VT), and frequency (f) were compared in 23 rats while either awake and unrestrained or anesthetized. FRC was determined from gas compression with closed airway inside a cone-shaped body plethysmograph. In the awake state (mean +/- SD), FRC was 1.02 +/- 0.22 ml/100 g, VT was 0.38 +/- 0.06 ml/100 g, and f was 142 +/- 22 breaths/min. During anesthesia, FRC decreased (P less than 0.01) to 52.9% of awake values, VT increased (P less than 0.01) to 147.4%, and f decreased (P less than 0.01) to 71.8%, leaving minute ventilation almost unchanged. An additional seven rats were used to examine postural effects on FRC during anesthesia, and in another seven animals pleural pressure changes were monitored. Dynamic lung compliance (0.80 ml . kg-1 X cmH2O-1) was not altered by anesthesia, but the pressure-volume curve was shifted 6 cmH2O higher. Thoracic compression, followed by a time-dependent effect of volume history, may account for the major change in FRC. The remainder of the decrease in FRC may be due to lower breathing frequency, loss of inspiratory muscle activity, and/or less airway resistance after anesthesia. Peak diaphragmatic electromyogram per unit VT was shown to increase almost linearly with FRC, indicating that diaphragmatic efficiency was decreased as lung volume was elevated.

Phytobezoar of Persimmon Origin

In 1935, Dr. Harry C. Schmeisser, of Memphis, Tenn., reported1 two cases of phytobezoar of persimmon origin, and in his search of the literature he had found 30 authentic cases of this type, his own two cases making 32. The one reported below makes 33. Case 1. F. H., white, male, a farmer, aged 59 years, was admitted to the Veterans' Hospital for treatment of hemorrhoids. He was sent to the x-ray department for a routine gastro-intestinal examination on Nov. 9, 1935, with a history of gastro-intestinal distress. The fluoroscopic examination clearly demonstrated that there was a foreign body in the stomach. In fact, on manipulation, the observer realized that he was dealing with two foreign bodies. In the first examination, it was rather difficult to dislodge the cone-shaped body in the pyloric end of the stomach, but the larger half of the mass could be freely moved in the cardiac end. The patient was asked to return on the following morning for further investigation. On his arrival, the next day, he remarked that the manipulation had cured him, as he had had a comfortable night and felt fine. After the discovery of these foreign bodies, the observer immediately thought of the phytobezoar of persimmon origin and questioned the patient along this line. His story was a classic. History. — The patient had had chronic constipation extending back over a period of at least 20 years, but had been considerably worse during the past year. He had taken cathartics, and for the past seven months it had been necessary to take a cathartic of some kind or there would be no bowel movement at all. He had a considerable accumulation of gas in the gastro-intestinal tract at times. Occasionally, he was slightly nauseated but there had been few attacks of vomiting. He had no history of epigastric pain. There had been no vomiting of blood, nor bleeding from the intestinal tract other than from the hemorrhoids for which he was admitted to the hospital. His gastro-intestinal symptoms bore no relation to meals and were not seasonal in type. He denied that he had ever been jaundiced. The patient gave no history of any edema of the feet nor any great amount of dyspnea, although he stated that at times he had had fainting sensations, which had been ascribed to his gastro-intestinal condition. The patient was in James Walker Hospital, Wilmington, N. C., for a period of treatment for the gastro-intestinal condition mentioned above. While there, he was put on a rather scant diet consisting of milk and cereals. He was discharged from that hospital on Sept. 7, 1935, and on the following day, being still on a very scant diet, his stomach was empty and he felt very hungry. In short, while he was out in the field where some persimmon trees grew, he ate persimmon fruit—he estimated the amount to be perhaps one and one-half pints. This was about four o'clock in the afternoon. He returned to the house and ate nothing further before retiring except some soup.