Vertical Pressure Vessels Research Articles

NUMERICAL ANALYSIS OF STRESS STATE OF PRESSURE VESSEL

<p style="text-align: justify;">Pressure vessels that are exposed to high stresses, due to unfavorable working conditions during exploitation, must be properly designed, taking into account all calculation factors, in order to be safe during their expected lifetime. Checking the condition of the vessel, or analyzing the load of the vessel in working and test conditions, is mandatory. In recent times, numerical analysis represents one of the most important methods of analyzing the stress states of all structural elements, including pressure vessels. It enables precise determination of the location of the greatest stresses and deformations. In this paper, a stress analysis of a vertical cylindrical pressure vessel type VS 110 with a spiral for heating and cooling, with a volume of 3750 liters and a working pressure of 3 bars, which is used for the preparation of medicines in the pharmaceutical<br />industry, was performed. The calculation of the vessel was made according to the EN 13445 standard and regulations on pressure vessels. Then a numerical stress analysis was performed in the Autodesk Inventor 2023 software package. The results of the numerical analysis show that the highest stresses occur in the torispherical parts of the vessel end. Furthermore, the cylindrical nozzles on the shell as well as on the torispherical ends act as a reinforcement of the vessel because there is a stress reduction in their vicinity.</p>

Analysis of vertical pressure vessel with skirt support

Analysis of vertical pressure vessel with skirt support

Redesign of a Pressure Vessel for Operation at 1.71 MPa

Pressure vessel is a liquid or solid fluid container made using metal materials with pressure in it. Pressure vessels also have a variety of shapes, which generally include horizontal, vertical, and spherical pressure vessels. The components of pressure vessels include top head, bottom head, shell, and nozzle. This study aims to obtain the geometry value of the pressure vessel which will be made geometry modeling that will be evaluated stress distribution, buckling, personal frequency, wind load so that the results will be obtained which can later be used as a design reference. This pressure vessel has a pressure of 1.71 MPa and has an operating weight of 16,698 kg, with a height of 6,539 mm and a diameter of 2,250 mm which will be installed in the Ujung Pangkah gas field Gresik, East Java, Indonesia. The pressure vessel will be used to develop the Ujung Pangkah oil and gas reserves by exporting gas to the power plant in Gresik after onshore separation and processing. The oil will be processed, stored and exported by bulk tanker. This research method includes literature study, data collection and processing carried out during the internship, after which geometry modeling using solidworks software and FEM analysis using ansys software. The results of this report find that the design of the pressure vessel is in accordance with the ASMESec.VII Div. 1 and has been validated using FEM analysis using ansys.

Design and Analysis of a Typical Vertical Pressure Vessel Using ASME Code and FEA Technique

This study aims to address the hazards associated with the design and manufacture of pressure vessels used for storing dangerous liquids, specifically focusing on the increased demand for liquefied petroleum gas (LPG) worldwide. The construction of more LPG facilities necessitates the implementation of safer pressure vessels to mitigate risks such as explosions and leakage. The primary objective of this project is to design a vertical pressure vessel, in accordance with the American Society of Mechanical Engineers (ASME) code, capable of safely storing 10 m3 of pressurised LPG. To ensure the safety of the pressure vessel, the researchers employed Autodesk Inventor Professional 2023 for geometric modelling and utilised Inventor Nastran for finite element analysis (FEA) to investigate displacements, deflections, and von Mises stresses. The vessel is cylindrical in shape and features two elliptical heads, two nozzles, a manway, and four leg supports. The FEA analysis conducted using Autodesk Inventor Nastran enabled the researchers to identify areas where structural modifications were necessary to reduce stress within the vessel. The results revealed an inverse relationship between the displacement and the tank section shell thickness. Additionally, the factor of safety exhibited a linear increase as the shell thickness increased. The researchers carefully considered permissible pressures and determined the required wall thickness to maintain acceptable maximum stresses. The findings indicate that the design of the pressure vessel is safe from failure. Among the components, the manway experiences the highest stresses, followed by the shell, while the heads, nozzles, and leg supports experience lower stresses. The researchers also conducted theoretical calculations for the entire model and ensured that the results fell within acceptable limits, further validating their design approach. The research emphasised the importance of designing pressure vessels in compliance with ASME codes to ensure safety and prevent hazards associated with improper design and manufacturing. The combination of Autodesk Inventor Professional and Inventor Nastran proved to be an effective approach for simulating and evaluating the performance of the pressure vessel. Through the analysis, the researchers found that changes to the pressure vessel structure were necessary to reduce stress. They observed an inverse relationship between displacement and tank section shell thickness, while the factor of safety increased linearly with shell thickness. Stress distribution analysis revealed that the manway and shell experienced the highest stresses, while the heads, nozzles, and leg support exhibited lower stresses. Employing the finite element method, potential stress points within the pressure vessel were identified, enabling necessary modifications to enhance its safety.

Local stress analysis of tailing lugs in a vertical pressure vessel

During the process of erecting a vertical pressure vessel from a horizontal to vertical orientation (0°to 90°) using tailing lugs, it is necessary to use a tailing lug with low local stress around the lug–shell attachment to prevent damage to the vessel shell during the lifting process. Two methods of local stress analysis, WRC-537 bulletin and FEA using ASME BPVC Section-VIII Division-2 are studied and evaluated in this paper. The WRC-537 method, which is known for being conservative, produced higher stress values compared to the FEA solution. This paper also examined the impact of various dimensional parameters related to tailing lug size and shape on local stress around the lug–shell attachment. In cases where single lug configurations fail to achieve the minimum required local stress values, paired lug configurations are purposed as a possible alternative solution towards reduced local stress. This paper also discusses the benefits of paired lug configurations over single lug configurations regarding the lower localized stress, especially for vessels with thin shells and large diameters. Paired lug configurations are found to have about four times lower localized stress compared to single lug configurations. When comparing rectangular and circular attachments, this study has found that rectangular attachments tend to have lower localized stress.

ANALISA KELAYAKAN BEJANA BERTEKANAN TIPE VERTIKAL DENGAN MENGGUNAKAN SIMULASI AUTODESK INVENTOR

The minimum thickness of vertical type pressure vessel of column type distillation, must be planned in accordance with the recommended code of ASME (The American Society of Mechanical Engineering) VIII Div 1. Based on this code, the study aims to determine the feasibility of a pressure vessel that used by PT Pertamina (Persero). For this reason, and to be able to use this ASME code, various data was needed, especially the data sheets and some required data from the field. Based on the data that has been collected, it is then processed and was made a 3D modeling and was simulated using Autodesk Inventor software to test its feasibility. Based on the results of the study, the minimum thickness was obtained, namely head 13.66 mm, shell 13.69 mm, and skirt 3.47 mm, respectively. Taking into account the availability of materials on the market, namely SA-516 Grade 70, the recommended thickness of the head and shell sections was 14 and 5 mm, respectively. From the results of the safety analysis, it was found that at the stress of 0.217, 0.197, 0.196, and 0.195 MPa, the Von Mises stress that occurred ware 0.249; 0.226, 0.225 and 0.224 MPa. From these data, based on the distortion energy failure theory, the head and shell materials which have yield strength of 260 MPa can be categorized as very safe because it does not exceed the yield strength of the material used.

Hybrid seismic isolation of vertical pressure vessels in CO2 capture plant

This study investigates the hybrid seismic isolation of vertical pressure vessels in the CO2 capture plant using high-damping viscoelastic isolators and a grounded tuned mass damper inerter (TMDI), to improve the resilience of the CO2 capture plant against earthquakes. The vessel with the hybrid isolation is modeled as a cantilever beam connected in series with a linear oscillator and a TMDI. A parameter design framework of the hybrid isolation is developed based on a simplified two-degree-of-freedom model and the Pareto front. Numerical simulations of a vertical pressure vessel with the conventional base isolation, the high-damping base isolation, and the hybrid base isolation subjected to historical earthquakes are performed. The results show that the hybrid base isolation has the best control result in reducing the displacement, stress, and isolator deformation among the three base isolations. The role of the TMDI in the hybrid base isolation is equivalent to further increasing the damping of the high-damping base isolation. The larger of the inertance in the TMDI, the better the control result of the hybrid base isolation. The hydrodynamics induced by the solvent has little influence on seismic responses of the vessel, but greatly weakens the control result of base isolations when the solvent height is high. The hybrid base isolation is more recommended for the vessel considering the hydrodynamics than the conventional base isolation and high-damping base isolation.

Study of the Stress Distribution Due to the Effect of Transient Analysis on a Vertical Pressure Vessel and Validation using the Mesh Independence Study

The importance of Pressure Vessel (PV) to industries is one of the reasons why the design and structural integrity should be fully understood and considered when deploring it in under different conditions. The design of such vessels need to be broadened with a detailed thermal stress due to its time-dependent different behaviours experienced under load. Therefore, this study aimed at investigation of transient analysis of PV when subjected to different operating condition. The PV used for this simulation was designed based on American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code (BPVC) 2019 and subjected to transient-stress analysis (transient thermal and structural) using ANSYS software. A complete evaluation of temperature, heat flux and resulting stress distribution across the vessel was estimated at four different locations within the designed PV and the obtained result was compared with analytically obtained results from appropriate standards. The accuracy of the result obtained from PV was validated using analysis of Mesh Independent Study (MIS), Grid Convergence Index (GCI) and fractional error obtained between the fine grid used. The results showed that there were different temperature and heat flux distribution at the considered locations, these varied distributions or change are according to various transients which are as a result of the load applied to the PV. The simulated maximum principal stress value was close to the analytically computed stress with a percentage error of 2.65% with respect to the analytically obtained result. The analysed maximum stress (W analysed) value 3400 MPa, obtained from MIS study was close to 3210 MPa obtained for maximum stress using numerical approach (WN). The GCI value obtained was 0.073 and fractional error of -0.003 which show that the result presented are grid independent solution.

Step by Step Stress Analysis of Ammonia Scrubber Vertical Pressure Vessel Using Finite Element Method

In order to solve the stress problem of ammonia scrubber pressure vessel, this paper proposes the analysis steps using finite element method. The study is a type of vertical pressure vessel used to remove pollutants in ammonia gas. Firstly, the modeling of the vertical pressure vessel geometry was carried out using Autodesk Inventor Professional 2017. Secondly, the meshing was carried out using Autodesk Nastran In-CAD 2017. For the meshing, we used tetrahedral element and we chose the parabolic type element order. Thirdly, the analysis was carried out using Autodesk Nastran In-CAD and based on the design pressure of 0,5 MPa with a volume of 1,21 m3. The results showed that the maximum stress occurred in the connection area between the inspection opening and the shell of 333,4 MPa. The maximum displacement occurred in the shell adjacent to the inspection opening was 3,268 mm. Based on ASTM standards on SA 240/A240M Gr 304 material, the maximum strength of material stress was 515 MPa. Finally, theoretical validation was carried out for the entire model, and the results were within the permissible limit.

Pressure Vessel Design by Design by Analysis Route

Pressure vessels are conventionally designed based on the Design by Rule (DBR) approach. Standard vessel geometries are designed using simple formulae and charts, formulated as standards and codes based on the rules proposed in the ASME Boiler and Pressure Vessel Code and the European Standard prEN13445-3. The stress categorization problem faced employing DBR methodology was overcome by employing Limit Load Analysis using the DBA approach. A simple unfired vertical cylindrical pressure vessel with torispherical pressure head and Y-forged skirt support was analyzed for its structural integrity using ANSYS software. The results obtained for two different materials, high strength steel P500-QT and the conventional low strength steel P355 employing DBA approach was compared with the calculated results using the DBR approach. The maximum allowable pressure (PMAX) for P500-QT material was found to be 2.5X the maximum pressure calculated using the DBR approach as per ASME codes and 3X times as per EN13445-3 standard. For P355 material the maximum allowable pressure (PMAX) was found to be 2.32X the maximum pressure calculated using the DBR approach as per ASME codes and 2.6X times as per EN13445-3. The DBR methodology proves to be highly conservative whereas the use of DBA leads to less conservative design parameters.

A low cost validation method of finite element analysis on a thin walled vertical pressure vessels

Pressure vessel is a container that has been used to contain a pressurized fluids, either oil, gas, or other chemical fluids. It is widely used for the oil, gas and other chemical based industries. Nowadays, finite element analysis is commonly used to reduce the high cost of testing a pressure vessel before manufacturing process. However, further validation is needed to ensure the results of the simulation and safety of the pressure vessels. In this study, theory of distortion energy is used as the tools of validation based on materials properties and behavior. And finally to ascertain wether the pressure vessel is possible for production or a refinement for safety is needed. The results of the study shown that theory of distortion energy can be used as validation tool for finite element analysis on a pressure vessels, however it cannot ensure the safety. Therefore other validation methods are needed to ascertain the safety of the pressure vessel discussed in this report. The cost analysis shown that failure theory combined with other calculation methods can save costs in pressure vessel testing, although some fairly expensive tests cannot be avoided.

Design and Analysis of a Vertical Pressure Vessel with Effect of Rotational Velocity on the Stresses and Deformation by using ANSYS

In this study, the suitability and influence of Rotational Velocity (RV) on the operating conditions of a vertical Pressure Vessel (PV) was investigated. A vertical PV was designed and analyzed with the aid of ANSYS. Effect of eight different parameters on the performance of the designed PV was analyzed. The results obtained from designed PV using Finite Element Analysis (FEA) was validated by comparing it with that obtained from Manually Computed Method (MCM) and Utilization Factor (UF) method. The results of this investigation show that the designed PV was safe within the specified operating condition, the FEA results are more accurate than that of MCM and presence of RV affected the stress distribution and deformation of the PV.

CFD modeling for nucleate pool boiling of nanofluids

Boiling is one of the most important processes in almost every industrial heat exchanger arrangement. The present study examines the role played by nanofluids in increasing the heat transfer rate which could improve process efficiency as well as operational cost. The setup consists of a stainless steel vertical cylinder pressure vessel having a horizontal heating rod made of stainless steel submerged in a pool of working fluid (distilled water, alumina/water nanofluid of variable concentration). Simulations were carried out using a 2D geometrical domain in order to calculate values of heat transfer coefficient for different constant heat flux applied on the heater at atmospheric as well as sub atmospheric pressures. For the simulations, a transient Eulerian multiphase involving boiling model was used along with various sub-models involving drag, lift, heat and mass transfer models. The simulated results for the value of heat transfer coefficient were compared and validated from the experimental results.

Hydrothermal Laboratory

The hydrothermal laboratory is equipped with horizontal and vertical cold-seal pressure vessels for the synthesis of crystals or glasses or to study interactions between minerals/rocks, melts, and fluids at hydrostatic conditions. An advantage is that long-term runs can be done to investigate equilibria between solid phases. This facility, operated by the Helmholtz Centre Potsdam GFZ German Research Centre for Geosciences, is open to all academic applicants, both national and international. There is no external steering board. Requests to use the laboratory are evaluated based on scientific quality and feasibility of the project.

Statistical method for the fatigue life estimation of coke drums

Coke drums are vertical pressure vessels used in the delayed coking process in petroleum refineries. They are operated under severe thermal–mechanical conditions by cyclic heating and quenching processes, which make them susceptible to damage. To accurately predict the safety lives of coke drums, a statistical fatigue life evaluation method is proposed in this study. To develop this method, thermal–mechanical cyclic fatigue tests of coke drum materials were firstly conducted to obtain strain-life curves, then simplified thermal-elasto-plastic analytical models were developed to calculate maximum equivalent strain amplitudes for global cycling and local hot and cold spot events. Statistical analysis of temperature data on a coke drum shell was also performed to get the probability distributions of the hot and cold spot events. The final statistical fatigue life evaluation model is based on Palmgren-Miner’s damage accumulation rule. The fatigue life of a selected coke drum is hereafter estimated according to the maximum equivalent strain amplitudes in both cladding and base plate. The predicted fatigue life of the coke drum is about 5000 operation cycles, which is within the range of operation cycles to the first-through-thickness crack in coke drums, reported by American Petroleum Institute (API) survey. The evaluation methodology developed in this study can be employed to predict the safety lives of coke drums and is expected to be helpful for the design and maintenance of the equipment.

Fatigue behaviour of coke drum materials under thermal-mechanical cyclic loading

Coke drums are vertical pressure vessels used in the delayed coking process in petroleum refineries. Significant temperature variation during the delayed coking process causes damage in coke drums in the form of bulging and cracking. There were some studies on the fatigue life estimation for the coke drums, but most of them were based on strain-fatigue life curves at constant temperatures, which do not consider simultaneous cyclic temperature and mechanical loading conditions. In this study, a fatigue testing system is successfully developed to allow performing thermal-mechanical fatigue (TMF) test similar to the coke drum loading condition. Two commonly used base and one clad materials of coke drums are then experimentally investigated. In addition, a comparative study between isothermal and TMF lives of these materials is conducted. The experimental findings lead to better understanding of the damage mechanisms occurring in coke drums and more accurate prediction of fatigue life of coke drum materials.

LUCI: A facility at DUSEL for large-scale experimental study of geologic carbon sequestration

LUCI, the Laboratory for Underground CO2 Investigations, is an experimental facility being planned for the DUSEL underground laboratory in South Dakota, USA. It is designed to study vertical flow of CO2 in porous media over length scales representative of leakage scenarios in geologic carbon sequestration. The plan for LUCI is a set of three vertical column pressure vessels, each of which is ~500 m long and ~1 m in diameter. The vessels will be filled with brine and sand or sedimentary rock. Each vessel will have an inner column to simulate a well for deployment of down-hole logging tools. The experiments are configured to simulate CO2 leakage by releasing CO2 into the bottoms of the columns. The scale of the LUCI facility will permit measurements to study CO2 flow over pressure and temperature variations that span supercritical to subcritical gas conditions. It will enable observation or inference of a variety of relevant processes such as buoyancy-driven flow in porous media, JouleThomson cooling, thermal exchange, viscous fingering, residual trapping, and CO2 dissolution. Experiments are also planned for reactive flow of CO2 and acidified brines in caprock sediments and well cements, and for CO2-enhanced methanogenesis in organic-rich shales. A comprehensive suite of geophysical logging instruments will be deployed to monitor experimental conditions as well as provide data to quantify vertical resolution of sensor technologies. The experimental observations from LUCI will generate fundamental new understanding of the processes governing CO2 trapping and vertical migration, and will provide valuable data to calibrate and validate large-scale model simulations. © 2010 Elsevier Ltd. All rights reserved

C. botulinum inactivation kinetics implemented in a computational model of a high‐pressure sterilization process

High-pressure, high-temperature (HPHT) processing is effective for microbial spore inactivation using mild preheating, followed by rapid volumetric compression heating and cooling on pressure release, enabling much shorter processing times than conventional thermal processing for many food products. A computational thermal fluid dynamic (CTFD) model has been developed to model all processing steps, including the vertical pressure vessel, an internal polymeric carrier, and food packages in an axis-symmetric geometry. Heat transfer and fluid dynamic equations were coupled to four selected kinetic models for the inactivation of C. botulinum; the traditional first-order kinetic model, the Weibull model, an nth-order model, and a combined discrete log-linear nth-order model. The models were solved to compare the resulting microbial inactivation distributions. The initial temperature of the system was set to 90 degrees C and pressure was selected at 600 MPa, holding for 220 s, with a target temperature of 121 degrees C. A representation of the extent of microbial inactivation throughout all processing steps was obtained for each microbial model. Comparison of the models showed that the conventional thermal processing kinetics (not accounting for pressure) required shorter holding times to achieve a 12D reduction of C. botulinum spores than the other models. The temperature distribution inside the vessel resulted in a more uniform inactivation distribution when using a Weibull or an nth-order kinetics model than when using log-linear kinetics. The CTFD platform could illustrate the inactivation extent and uniformity provided by the microbial models. The platform is expected to be useful to evaluate models fitted into new C. botulinum inactivation data at varying conditions of pressure and temperature, as an aid for regulatory filing of the technology as well as in process and equipment design.

Design by analysis versus design by formula of high strength steel pressure vessels: a comparative study

A comparative study for design by analysis and design by formula of a cylinder to nozzle intersection has been made using different finite element techniques. The cylinder to nozzle intersection investigated is part of a typical vertical pressure vessel with a skirt support. For the study the commonly used ductile P355 steel alloy and the high strength steel alloy P500 QT were considered. The comparative results clearly show disadvantages in terms of limit load capability when the design-by-formula procedures are used in the design of high strength steel pressure vessels. The FE results also clearly show advantages of the shell to solid sub-modeling technique, as it combines the accuracy of 3D-solid modeling with the affordable computing time of the 3D-shell modeling technique.

Rocket missiles generated by failure of a high pressure liquid storage vessel

A simple model has been developed for predicting the velocity of “rocket” missiles generated by failure at the lower end of a vertical cylindrical pressure vessel containing gas and a cold liquid. This model accurately predicts the velocities observed in a parallel experimental investigation. When modified to take account of liquid flashing to vapour during depressurization, the model has also been successfully applied to the case of “rockets” generated by failure of a vessel containing a hot liquid and a cover gas at a pressure sufficient to suppress boiling in normal operation. However, where “rockets” are generated by failure of a vessel containing a boiling liquid, the model significantly under predicts the “rocket” velocity in many cases. Here the enhanced experimental velocities are attributed to the increase in the apparent liquid volume, caused by the presence of the vapour bubbles, prolonging the liquid expulsion period. Simple correlations of the experimental data for all three cases have been developed using a parameter derived from the theoretical predictions. These define upper limit velocities for use in hazard assessment.