Head Cone Research Articles

Numerical investigation of the distributed combustion in the thermal choked solid fuel combined cycle engine

In this study, a solid fuel combined cycle engine concept based on the distributed combustion and the self-adaptive thermal choking is proposed, which can operate effectively within a wide Mach number range. By regulating the heat release through the distributed fuel injection, the thermal choking can be formed in the fixed geometry combustor. The air intake controls the flow capture and circulation area through the movement of its head cone, ensuring stable air breathing over a wide range. Numerical simulations conducted under Ma = 3.0 and 6.0 conditions using the validated Eulerian-Lagrangian method coupled with gaseous and particle reaction models demonstrate the concept's capability to operate within the Mach number range of 3.0–6.0, delivering improved mixing, combustion, and specific impulse performance.

Melting trajectory of the asymmetrically-heated conical thermal head for ice-melting probes

The development of ice-melting probes is driven by the scientific need to explore the subglacial aquatic environments, such as the subglacial lakes in Antarctica and subglacial water on some extraterrestrial planets. However, during the downward melting, a deviation of the melting trajectory might occur. If left unaddressed, the accumulated deviation will eventually lead to missing the probe's target. Therefore, it is necessary to build a theoretical model to describe the deviation for predicting the future melting trajectory and building the deviation correction system. The deviation comes from any asymmetric heating condition on the melting head. Generally, the Close-Contact Melting (CCM) theory is used to model the probe's melting process without any deviation, and there is only one attempt so far that applies the CCM theory to asymmetric heating conditions. Based on this initial attempt, we successfully expanded the CCM theory with asymmetric temperature profiles to conical thermal heads. Additionally, we simplified the model solving which leads to fewer influence factors compared to existing studies. The model indicates that the melting trajectory of a conical head is linear under asymmetric heating conditions, and the inclination angle of the trajectory is related to the ratio between the head's temperatures on each side and the head's cone angle. To validate the theoretical results, laboratory experiments have also been conducted with an innovative optical positioning method.

Numerical study of a composite cooling method for hypersonic aircraft

Thermal protection is a crucial issue for a long-flying hypersonic aircraft. In this work, a composite cooling method is proposed and implemented on a hypersonic blunt cone. The composite cooling method combines impinging and convective cooling at the cone head with transpiration cooling employed downstream to produce an overall cooling effect of the cone. Using computational fluid dynamics, the influences of the cooling gas and different attack angles on the cooling effect are examined. The results indicate that the combined cooling method can effectively reduce the overall outer wall temperature of the cone. In particular, with the combined cooling method, an increase in mass flow rate of the cooling gas has been observed in numerical tests, which results in a decrease in the head temperature. The maximum temperature decrease can reach 77.0% on the wall when the mass flow rate of the cooling stream is 1.1 kg/m2 s. The cooling performance on the leeward side can be better than that on the windward side for a fixed cooling gas mass flow rate. This gap in cooling performance between the two sides can be further amplified by a larger attack angle. Quantitatively, when using the combined cooling method, the temperature difference between the windward and leeward sides increases from 106 to 270 K when the attack angle increases from 4° to 8°. The numerical results in this study could provide theoretical and statistical guidance for the design of novel active thermal protection methods for hypersonic aircraft.

Failure analysis and design improvement of high-pressure seal cone head for vehicle hydrogen engine

As hydrogen energy vehicle technology advances, the performance requirements of vehicle hydrogen engine components become increasingly stringent. The high-pressure sealing cone head is a vital connection of the vehicle's hydrogen engine, however, it is easily fractured during the loading test. To address this issue, this research combines finite element modeling and material characterization methodologies to perform failure analysis and re-optimization design of the sealing cone head. First, the parameters for the CL toughness fracture criteria and the Johnson-Cook constitutive model were obtained by the inversion technique and the tensile test, respectively. On the cold heading formation process of the cone head, finite element analysis and microstructure analysis were performed. The results show that machining defects on the outer surface are the root cause of failure. Fatigue cracking is the main failure mechanism, and the crack gradually expands under the effect of alternating loads, which eventually causes a fracture of the cone head. At the same time, there are bending-type folding defects caused by the instability of the cone head under pressure. Second, the critical structural and process factors that impact the mechanical behavior of the components are investigated, and the orthogonal experiment optimization method is utilized to find the optimal process parameters, using the damage value as the evaluation index. According to the findings, the die angle has a major impact on the damage value, but the eligible die angle that is too small would negatively affect the force of the cone head and nut. Finally, a multi-station cold heading procedure for the high-pressure seal cone head was innovatively presented, and its mechanism of action was unveiled. The aforementioned defects were effectively addressed by the optimized process, and as compared to the pre-optimization, the maximum principal stress of the optimized component in the C-region was reduced by 27%, which did not exceed the tensile strength. At the same time, the spindle load was decreased by 25% and the maximum damage value was decreased by 48%, reaching the safe range. The optimized process effectively improves the performance of the part and increases the quality stability.

Ballistic Characteristics of High-Speed Projectiles Entering Water Vertically

The formation of supercavitation after a high-speed projectile enters water has a decisive impact on the underwater ballistic and penetration of the projectile. In this study, Ansysfluent19.0 simulation software is used to study water entry of a chosen projectile at velocities of 300, 400, 500, and 600 m/s. The underwater cavitation characteristics, trajectories, and flow-field characteristics are analyzed for a 5.8-mm caliber conical flat head projectile, as well as for t wo other projectiles of the same caliber and different head shapes — conical cone head and elliptical flat head — entering water vertically at the same velocities. The attenuation rate of water entry velocity increases with the increase of velocity. Within first 3ms, the velocity attenuation rate of the conical flat-head projectile with a water entry velocity of 600m / s is 55.6 %, while the velocity attenuation rate of the projectile with a water entry velocity of 300m / s is only 16.3 % within 3ms. Among the head shapes considered, the conical flat head projectile is the most stable for vertical water entry. The stability of an elliptical flat head projectile is worse, and the trajectory stability of a conical cone head projectile is still worse

Analysis of TB2 rivet forming quality and mechanical properties of thin sheet riveted joints based on different riveting methods

The riveting of high-strength rivets (such as TB2 (Ti-5Mo-5V-8Cr-3Al)) faces difficulties in forming. This article compares the electromagnetic riveting (EMR) and the hot riveting (HR) joints of two typical TB2 rivets (the flat cone head rivet and the countersunk head rivet). The interference and hardness distributions of the rivets were measured, and the strength of the joints was tested. Moreover, the microstructures of rivets after riveting and the fractured surfaces after the shear and pull-out tests were both observed. The results indicate that the interference of the EMR joints is greater and more uniform than that of the HR joints. The deformation of the EMR driven head is more severe than that of the HR. Higher hardness is measured in the driven head and the rivet shank at the positions of severe deformation. The hardness of the EMR driven head and rivet shank is higher than that of the HR. Additionally, it will not cause a decrease and even slightly improve in the mechanical properties of the joint when using the EMR riveting TB2. The pull-out strength of flat cone head rivet joints is significantly higher than that of countersunk rivet joints due to the influence of the structure strength of the manufactured head. The fracture mode of all joints is mixed fracture. However, the failure mode of joint varies greatly due to the influence of rivet structure and riveting method. When using the EMR instead of the HR to rivet the TB2 rivets, it will not cause a decrease in the mechanical properties of the joint. Therefore, it is indicated that the EMR can be used to replace the HR.

Cone–hole docking mechanism for a modular reconfigurable mobile robot and its characteristic analysis

Purpose The purpose of this paper is that the modular mobile robots reformed the multimachine joint mode to achieve obstacle-crossing, climbing and other multifunctional inspection in unstructured environment under the connection of the cone–hole docking mechanism. Design/methodology/approach An arc-shaped docking cone head with a posture-maintaining spring and two arc-shaped connecting rods that formed a ring round hole were designed to achieve large tolerance docking. Before active locking, the coordination between structures was used to achieve passive locking, which mitigated the docking impact of modular robots in unstructured environment. Using the locking ring composed of the two arc-shaped connecting rods, open-loop and closed-loop motion characteristics were obtained through the mutual motion of the connecting rod and the sliding block to achieve active locking, which not only ensured high precision docking, but also achieved super docking stability. Findings The cone–hole docking mechanism had the docking tolerance performance of position deviation of 6mm and pitch deviation of 8° to achieve docking of six degrees of freedom (6-DOF), which had a load capacity of 230 N to achieve super docking stability. Under the connection of the cone–hole docking mechanism, the modular mobile robots reformed the multimachine joint mode to achieve obstacle-crossing, climbing and other multifunctional inspection in unstructured environment. Originality/value Based on mechanical analysis of universal models, a cone–hole docking mechanism combining active and passive functions, six-dimensional constraints could be implemented, was proposed in this paper. The characteristics of the posture-maintaining spring in the cone docking head and the compression spring at the two ends of two arc-shaped connecting rods were used to achieve docking with large tolerance. Passive locking and active locking modules were designed, mitigating impact load and the locking did not require power to maintain, which not only ensured high precision docking, but also achieved super docking stability.

Raman Spectroscopy and STR Analysis of the Elongated Skulls from the Paracas Mummies of Peru

Between 1880-1947, several hundred mummified bodies were excavated from burial sites in the Paracas peninsula of Peru. Each set of recovered remains displayed reduced stature and severe cranial elongation, which led many anthropologists and archaeologists to question the genetic origins of what would be colloquially referred to as the “Cone Head mummies.” Since the discovery of these bodies, suggestions have been made that the mummies’ cranial deformations point to another human species, an unknown hominid species, or even within some groups, an alien. This project sought to employ commonly used forensic techniques, including but not limited to Raman spectroscopy and DNA fingerprinting, to investigate the hair structure and genetic profile from tissue and hair samples derived from the Paracas skulls. Tissue and hair samples were subjected to comparative hair analysis, Raman spectroscopy, and DNA typing using short tandem repeat (STR) analysis. Comparative microscopic hair analysis and Raman spectroscopy of samples collected from the Paracas skull as well as from humans of varying ethnicities revealed very similar hair structures and characteristics that are associated with human hairs. Following DNA extraction and amplification of tissue samples, STR typing results demonstrated allelic profiles similar and consistent with those DNA profiles observed in modern human populations. Moreover, no foreign DNA or unusual patterns/profiles were observed in any of the samples tested. Data generated to this point strongly suggest that the Paracas mummies are of the same species as humans and not from an unknown hominid or alien society.

Modeling and characteristic analysis of roadway profile under the influence of multiple factors

Considering that the movement trajectory of roadheader cutting head directly affects the surface morphology characteristics of roadway forming, the creation mechanism of roadway contour obtained by cutting head cutting roadway is analyzed. The robot kinematics analysis method was used to determine the coordinates of the roadheader cutting head in the roadway space coordinate system, and the mathematical model of the cutting head cutting the roadway contour was constructed. Through numerical calculation, the differences of roadway morphology characteristics formed by three different types of cutting heads are analyzed. The orthogonal experiment was designed, and the regression equation under multiple factors was solved with the experimental results. The influence of cutting feed rate, cutting Angle, cutting head radius and cutting head cone Angle on the morphology characteristics of cutting surface was analyzed by regression calculation and theoretical calculation. The research results show that the roadway surface obtained by "spherical crown + cylinder" cutting head is the most uneven, and the roadway surface obtained by "spherical crown + cone + cylinder" cutting head is the most flat. With the decrease of cutting lifting Angle, cutting feed, cutting head cone Angle and the increase of cutting head crown radius, the smoothness of roadway obtained by cutting is higher.

Research on the characteristics of cavitation flow and pressure load during vertical water exit of different head-shaped vehicles

It is a complex process for a vehicle to emerge from the water. During this period, the cavitation flow state and the load on the vehicle change sharply, which has a great impact on the movement of the vehicle. It is necessary to study the cavitation flow state and loading characteristics during the process of water-exit. At present, the research on this aspect at home and abroad mostly focuses on the use of commercial software or self-written programs to simulate the pressure distribution on the surface of the extended vehicle and the flow field at the head of the vehicle during the process of water exit. However, there is a lack of relevant experimental data on the changes of pressure and cavitation flow regimes during the water-exit process of different head-shaped vehicles. The research on water plumes mostly focuses on the interaction between the explosion bubble and the free surface, but there is little research on the water plumes generated when different head-shaped vehicles exit the water. Based on this, this paper designs a set of surface pressure load measurement system for the water-exit process of the vehicle under the decompression environment, and designs and processes the vehicle with different head types such as cone head, hemispheric head, and swelling conical head. The flow characteristics and pressure loads of different head-shaped vehicles in the initial stage, development stage and collapse stage of cavitation were studied. The study found that the shape of the vacuoles in the initial stage, the development stage and the collapse stage of different head-shaped vehicles is quite different, and the change process of the pressure is also different; In addition, the water plumes generated when the vehicle is out of water can be divided into three categories according to the collapse method, and the collapse time of each type are also different.

Coupling Relationship between Altitude and Line-of-Sight Angle of Imaging Deviation in Cone Head Aero-Optical Flow Field

Coupling Relationship between Altitude and Line-of-Sight Angle of Imaging Deviation in Cone Head Aero-Optical Flow Field

Experimental and numerical studies on a new type of bolt-ball joint for spatial grid structures

The insufficient tightening due to workmanship and bolt loosen during the life cycle of spatial structures are common safety hazards in the installation process and the use stage of spatial structures. To tackle these problems, in this paper, a new type of bolt-ball joint with octagonal high-strength bolt is developed for conventional spatial structures. For this new type of node, the force was transmitted through the contact between the high-strength bolt and the inner wall of the octagonal sleeve, and the bolt is screwed into the bolt ball to avoid the shear forces on the pins. After installation, by checking whether the tail of the pin is flush with the outer surface of the sleeve, it will be easy to judge whether the high-strength bolt is properly tightened. To investigate the behavior of this new type of nodes, an experimental study on the tensile performance of octagonal high-strength bolts was performed. It is found that, the tensile strength of the octagonal high-strength bolts for this new type meets the requirements of the Chinese specification. Further detailed experimental studies and numerical simulations were carried out to investigate other nodes, namely steel-pipe, cone head/sealing plate nodes. The results show that the stress distribution and dimensions of the whole joints and the bearing capacity of the cone head are similar between the two nodes. The compressive test of the proposed new type of sleeve is also carried out, and the results show that the failure load is more than 3 times the required design value. Finally, the torsion bearing capacity test of this new type of node is carried out. The results show that the torsional bearing capacity of the new nodes during installation is much greater than that of the traditional ones.

Developing the technology of associated gold recovery when concentrating copper-pyrite ore

Research objective is to address an up to date task of developing the technology of associated gold recovery from complex ore. Object of research is the gold-bearing copper-pyrite ore. Gold was recovered in laboratory conditions with the use of gravity methods of mineral separation. Research tools. Rational modes of machinery operation have been determined through mathematical planning of experiments including the obtained results processing by mathematical and statistical methods. Methods of research. Gold was recovered in the grinding-classification circuit based on a seriesinstalled short-cone hydrocyclone, a jigging machine and a shaking table. Research results. The developed jig mode differs from the existing ones by the closed-circuit of jig machine chambers: from the feed of the second (in the direction of the light fraction travel) jig chamber, the light fraction (tailings) and undersize product – fraction with the increased content of accessory minerals (rough concentrate) are separated. The rough concentrate in the second chamber is directed to the first chamber of the machine, where the finished jig concentrate is obtained in the form of an undersize product. The light fraction moves from the first chamber to the second and is removed from the machine through the tail board. When fine-tuning the heavy fraction of jigging on a shaking table, it is recommended to mix 1/2 part of the initial feed of the tables with the rough concentrate isolated from the other 1/2 of the original feed. The new jigging mode and the scheme of concentration on the tables provide an increase in the gold content in the initial feed of the apparatus, which is the reason for a decrease in gold losses with the tails of the gravity circuit. Research relevance. Gold recovery increment by 4.77% was obtained due to the use of all three recommended scientific and technical measures, namely sands concentration in a short head cone crusher on a jig, switching the jig chambers to a closed circuit, and jet motion of concentrates on shaking tables. Scope of the results. The results should be applied when concentrating ore containing free (amalgamable) gold, as well as gold-bearing pyrite.

Effect of upper layer immiscible liquids on the water entry phenomena

The influence of a thin upper layer liquid on the cavity dynamic and the phenomena of solid bodies entering into a two-layer system of immiscible liquids are experimentally studied. The new phenomenon is seldom documented in the literature. The thin upper layer silicone oil can affect the cavity profile, the seal time (surface and deep), and the pinch-off position of the cavity. The cavity dynamics and water entry phenomenon of the bullet with different diameters and head cone angles under varying upper layer liquid are studied. The critical Froude number (from deep seal to surface seal) is affected by the cone angle and the upper layer liquid. The pinch-off time of the deep seal cavity is affected by the diameter of the bullet but has nothing to do with the upper layer liquid and cone angles.

Force and pressure function formulation for direct cold extrusion of aluminum alloy Al 1350 using regression method

Purpose. Establishing methodology in order to determine mathematically both extrusion force and pressure functions for Aluminum alloy AL 1350 using the regression method of experimental data. Methodology. Several variables (diameter of the cavity for pressing D, degree of extrusion, angle of the punch head cone 2, and ratio of the semi-finished sizes Rs) were included when using the regression method considered. Findings. Diameter and strain were found to play a significant role in predicting both extrusion force and pressure functions associated with the extrusion process. Mathematical formulas for force and pressure were obtained using the regression method. Amethodology has been developed for the mathematical determination of extrusion force and pressure. Originality. Force and pressure functions in direct cold extrusion process are mainly required for the design of extrusion dies. However, the existence of such data in the literature is insufficient to implement the process for direct cold extrusion of aluminum and aluminum alloys as well as for other materials. Results of the study consider the main factors influencing extrusion force and pressure as well as the main differences for types of aluminum alloys. Practical value. The mathematical formulas obtained by the regression method provide a mathematical tool for calculating force and pressure values in direct extrusion process.

Geometric analysis of cone crusher liner shape: Geometric measures, methods for their calculation and linkage to crusher behaviour

This paper presents a set of related methods for performing a computational geometry analysis of a cone crusher shape that provides geometric information for use in understanding cone crusher flows and breakage and their variation with key crusher geometric parameters. Algorithms that are able to calculate geometric measures such as the variation of the cross-sectional area available for flow at each height in the crusher, open and closed side areas, geometry based reduction ratios, eccentric throw as well as the open and closed side setting are described. These are demonstrated in a worked example of a specific short head cone crusher showing how systematic variation in the cone vertical displacement and eccentric angle affects geometric measures. Both the OSS and CSS are found to vary almost linearly with cone height and eccentric angle. The eccentric throw is found to be nearly invariant for changes in cone height but to vary strongly with eccentric angle. There is close to a linear relationship between variation in choke area (representing throughput) and the CSS (representing maximum product size) when the cone height is changed. In contrast, the choke area is almost independent of the CSS when the eccentric angle is varied meaning that throughput and breakage top size are independently controllable. Linear and area-based estimates of the reduction ratio can be used to bound the likely breakage performance. This analysis can be used in conjunction with DEM models to help to guide the evolution of liner configurations.

Influence of head structure on hydrodynamic characteristics of transonic motion projectiles

The hydrodynamic characteristic of transonic motion projectiles with different head diameters are investigated by numerical simulation. Compressibility effect in liquid-phase water are modeled using the Tait state equation. The result shows that with increasing of velocity the compression waves transfer to shock waves，which cause the significant increasing of pressure and decreasing the dimensions of supercavities. While the increasing of head diameter, the thickness, the vapor volume fraction and the drag coefficient of supercavities are all enhanced, which is conducive to the stability of transonic-speed projectiles. The cavity dynamics of the different head projectiles are compared, and the results shows when Mach number is in high region, the truncated cone head projectile is enveloped by a cavity which results in less drag and better stability.

Absence of Gasping Breaths and Failure of Respiratory Autoresuscitation in Neonatal Rats Studied Under Ethyl Carbamate (Urethane) Anesthesia

Respiratory autoresuscitation is a well‐described process that facilitates recovery and survival following an acute exposure to a severe hypoxemic event. In adult rats, our laboratory has shown urethane anesthesia prevents autoresustitation and causes predictable cardiorespiratory collapse and sudden death as a result of even a single episode of severe hypoxemia. This effect was confirmed to be a direct consequence of failure to gasp and restore rhythmic breathing. Given these findings, we hypothesized that neonatal rats would also experience significant disruption of the respiratory autoresuscitation process, negatively impacting their survival from a severe hypoxemic event. To test our hypothesis, we studied 4 male and 5 female rat pups aged P11–13. Animals were divided into two experimental groups, defined by the anesthetic used to study animals. The urethane (URE, n=5, 3f/2m, 31±3g, 12.2±0.8 d) group was anesthetized with urethane (1.2 – 1.5 g/kg i.p.), and the ketamine‐xylazine (KET, n=4, 2f/2m, 35±5g, 13.0±0.8 d) group was anesthetized with ketamine‐xylazine (40/5 mg/kg i.p.). Animals were maintained at a rectal temperature of 35±0.3°C, equipped with a head cone to monitor breathing (VE) and ECG electrodes to monitor heart rate (HR). VE and HR were continuously monitored while breathing room air, and subsequently a mild hypoxic gas mixture (FiO2=0.10, balance N2). Following recovery, animals were monitored during exposure to acute severe hypoxemia (breathing 100% N2), access to normoxic air was restored (FiO2 = 0.21) once respiratory arrest occurred, and opportunity for spontaneous respiratory autoresuscitation was provided. Pending successful autoresuscitation, animals were allowed to recover to baseline, and received another exposure to severe hypoxemia. This was repeated up to 4 times before the animal was exposed to terminal asphyxia for purposes of euthanasia. Baseline VE (16.0±4.1 vs 19.2±10.0 mL/min), HR (357±18 vs. 308±79 bpm) were not different between URE and KET animals, nor were VE or HR during steady‐state in mild hypoxia. During exposures to severe hypoxemia, the interval between the onset of exposure and respiratory arrest were not different between conditions (26.2±7.2 sec vs. 28.2±3.2 sec), but the amplitude of the peak ventilatory response during severe hypoxemia before respiratory arrest was significantly smaller in the URE vs KET condition (30.2±10.2 vs. 50.3±15.3 mL/min). All animals in the KET group successfully autoresuscitated from 4/4 exposures to severe hypoxemia. In the URE group, 0/5 animals successfully autoresuscitated and none expressed a single gasping breath following respiratory arrest. In neonatal rats, urethane anesthesia causes fatal disruption of respiratory autoresuscitation in response to a single acute exposure to severe hypoxemia, preventing gasping breaths and normal restoration of eupneic breathing. These results demonstrate that urethane provides a pharmacological model of sudden death in response to severe hypoxemia that is relevant to the neonatal stage of development.Support or Funding InformationJAR was the recipient of a CMU COM Summer Research Scholars Award. Additional intramural funding provided to HJB through CMU COM and ORSP.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Influence of electrodes area ratios and the discharge volume in RF capacitively coupled plasma

Experimental results on harmonic distortions in 13.56 MHz RF Argon glow discharge using different grounded electrodes areas and electrodes spacing are presented. The experiment is carried out at four pressure values. RF power values used are between 20 and 90 watts. The results indicate significant increase in distortions at two specific values of the cone angle enclosing the two electrodes within its geometrical volume. The computation of the cone head angle gave the symmetry discharge or asymmetry as well as when the angle is small the condition is near symmetry discharge associated with decrease in the nonlinearity.

Prediction Method for Overconsolidation Ratio of Marine SoftSoil Based on the Piezocone Penetration Tests

Because of the strong structural and sensitive behavior, the properties of marine soft soil change greatly when subjected to external disturbances, which leads to great difficulty in reflecting its real mechanical properties in the laboratory soil tests. The piezocone penetration test (CPTU) is one of the main technologies for in situ testing of geotechnical engineering. CPTU has the advantages of being fast and convenient, no sampling, low disturbance to soil, large amount of data, and reliable testing. The determination of the overconsolidation ratio (OCR) based on the CPTU results can solve the problems of soil disturbance and stress release, which occur during the consolidation test in the laboratory. However, there are still some problems such as lack of strict theoretical analysis of penetration mechanism and incomplete interpretation theory of in situ test parameters of CPTU. In this paper, the CPTU cone head is assumed to be hemispherical considering the penetration mechanism of CPTU. Moreover, the compaction modes of the CPTU probe penetrating into soil are adopted as spherical and cylindrical cavity expansion modes, respectively. The ultimate expansion pressures of the probe penetrating into soil under the spherical and cylindrical cavity expansion modes are first obtained by virtue of the theory of cavity expansion. Then, two prediction methods for OCR considering the roughness and penetration rate of the cone are proposed by combining the ultimate expansion pressures of the probe penetrating the approximate closed solution of cavity expansion in the modified Cambridge model, which is suitable for predicting the OCR of marine soft clay. Finally, to verify the reliability of the two proposed prediction methods, comparisons with the in situ CPTU tests of marine soft clay in two coastal areas and two existing prediction methods are made. The comparison results show that predictions of OCR of marine soft clay in this paper are close to Wayne’s method and more accurate than Chanmee’s method since the factors such as cone roughness and penetration rate are considered in the new proposed prediction methods. In order to improve the applicability in different cases of the OCR predictions, the average values of the two proposed methods are recommended as the reference value for the OCR of marine soft soil.