Elastic and elastic-plastic finite element analysis of hollow tubes with axisymmetric internal projections under combined axial and pressure loading

2001 ◽  
Vol 36 (4) ◽  
pp. 373-390 ◽  
Author(s):  
S. J Hardy ◽  
M. K Pipelzadeh ◽  
A. R Gowhari-Anaraki

This paper discusses the behaviour of hollow tubes with axisymmetric internal projections subjected to combined axial and internal pressure loading. Predictions from an extensive elastic and elastic-plastic finite element analysis are presented for a typical geometry and a range of loading combinations, using a simplified bilinear elastic-perfectly plastic material model. The axial loading case, previously analysed, is extended to cover the additional effect of internal pressure. All the predicted stress and strain data are found to depend on the applied loading conditions. The results are normalized with respect to material properties and can therefore be applied to geometrically similar components made from other materials, which can be represented by the same material models.

1996 ◽  
Vol 31 (1) ◽  
pp. 25-33 ◽  
Author(s):  
S J Hardy ◽  
M K Pipelzadeh

This paper describes the results of a study of the elastic–plastic behaviour of short flat bars with projections subjected to monotonic and cyclic axial loading using finite element analysis. The results are complementary to similar results for (a) shear loading and (b) combined axial and shear loading. Six geometries are considered and elastic–plastic stress and strain data for both local and remote restraints are presented. These geometries and associated restraints result in elastic stress concentration factors in the range 1.69–4.96. A simple bilinear elastic–plastic material model is assumed and the results are normalized with respect to material properties so that they can be applied to geometrically similar components made from other materials which can be represented by the same material models.


2014 ◽  
Vol 136 (2) ◽  
Author(s):  
Zhanghai (John) Wang ◽  
Samuel Rodriguez

In fitness for service (FFS) assessments, one issue that people often encounter is a corroded area near a structural discontinuity. In this case, the formula-based sections of the FFS standard are incapable of evaluating the component without resorting to finite element analysis (FEA). In this paper, an FEA-based technical approach for evaluating FFS assessments using an elastic-plastic material model and reformed criteria is proposed.


Author(s):  
Muhammad Abid ◽  
Abdul W. Awan

A number of analytical and experimental studies have been conducted to study ‘strength’ and ‘sealing capability’ of bolted flange joint only under internal pressure loading. Due to the ignorance of the external i.e. axial loading, the optimized performance of the bolted flange joint can not be achieved. A very limited work is found in literature under combined internal pressure and axial loading. In addition, the present design codes do not address the effects of axial loading on the structural integrity and sealing ability of the flange joints. From previous studies, non-gasketed joint is claimed to have better performance as compared to conventional gasketed joint. To investigate non-gasketed joint’s performance i.e. joint strength and sealing capability under combined internal pressure and any applied external loading, an extensive 3D nonlinear finite element analysis is carried out and overall joint performance and behavior is discussed.


Author(s):  
Avinash Shaw ◽  
Heramb Mahajan ◽  
Tasnim Hassan

Abstract Printed Circuit Heat Exchangers (PCHEs) have high thermal efficiency because of the numerous minuscule channels. These minuscule channels result in a high thermal exchange area per unit volume, making PCHE a top contender for an intermediate heat exchanger in high-temperature reactors. Thousands of minuscule channels make finite element analysis of the PCHE computationally infeasible. A two-dimensional analysis is usually performed for the PCHE core, which cannot simulate the local channel level responses reasonably because of the absence of global constraint influence. At present, there is no analysis technique available in the ASME Code or literature that is computationally efficient and suitable for engineers to estimate PCHE local responses. A novel but practical two-step analysis framework is proposed for performing PCHE analysis. In the first step, the channeled core is replaced by orthotropic solids with similar stiffness to simulate the global thermomechanical elastic responses of the PCHE. In the second step, local submodel analysis with detailed channel geometry and loading is performed using the elastic-perfectly plastic material model. The proposed two-step analysis technique provides a unique capability to estimate the channel corner responses to be used for PCHE performance assessment. This study first developed a methodology for calculating the elastic orthotropic properties of the PCHE core. Next, the two-step analysis is performed for a realistic size PCHE core, and different issues observed in the results are scrutinized and resolved. Finally, a practical finite element analysis framework for PCHEs in high-temperature nuclear service is recommended.


2010 ◽  
Vol 2010.48 (0) ◽  
pp. 17-18
Author(s):  
Takuma Niiya ◽  
Shingo Okamoto ◽  
Osamu Miyauchi ◽  
Jae Hoon LEE ◽  
Mutsuya Yamamoto ◽  
...  

1984 ◽  
Vol 106 (2) ◽  
pp. 166-171 ◽  
Author(s):  
D. K. Williams ◽  
G. D. Lewis

A finite element analysis of a trunnion elbow support is presented for the case of a long radius elbow subjected to an internal pressure loading. The stress results are categorized as average and linearly varying (through the thickness) stresses. The resulting stresses are then interpreted per Section III of the ASME Boiler and Pressure Vessel Code from which the primary and secondary (B1 and C1) pressure stress indices are developed. Several analysis were performed on various structural geometries in order to determine empirical relationships for the stress indices as a function of dimensionless ratios.


Author(s):  
Hao Gong ◽  
Jianhua Liu

Finite element analysis has been regarded as an effective research method for analyzing the loosening failure of bolted joints under vibration. However, there exist some factors, which influence the accuracy and reliability of loosening results, thus determining the explanations of the loosening mechanism. In this study, a 3D finite element model of a typical bolted joint was built to investigate the effects of several different factors on the loosening under transverse vibration loading. These influencing factors include preload generation, vibration parameter, and material model. Based on the simulation results, it was found that applying the method of pretension element to generate preload instead of the actual method of torque was reliable and efficient. For the vibration parameter, it showed that the decrease rate in preload was higher for a larger vibration amplitude. But once the bearing surface reached complete slip, the loosening rate would keep constant. This was because the thread surface at that time reached a sticking state. Vibration frequency was proved to have no effect on the loosening behavior. This result demonstrated that the quasi-static assumption for vibration frequency was reasonable. Additionally, it also indicated that plastic material models only affected the preload loss in the initial several vibration cycles and had no influence on the loosening rate of preload after several vibration cycles. Finally, experiments were conducted to confirm qualitatively the results obtained based on finite element analysis.


2011 ◽  
Vol 341-342 ◽  
pp. 416-420 ◽  
Author(s):  
Mahdi Maarefdoust ◽  
Pooria Akbarzade

Limit load analysis of defect free thick walled pipes and cylinders subjected to internal pressure and combined internal pressure and axial loading is commonly performed as part of integrity assessment procedures for transmission pipelines and pressure vessels across the industry. Moreover the potential impact of environmental assisted or accidental damage that result in creation of surface defects and consequently affects the ability of vessel to withstand the applied loading conditions. This paper attempts to demonstrate the effect of surface defects on the limit load of cylinders by use of finite element method. ABAQUS software has been used for FE analysis and modeling. Approximate analytical solutions for benchmark model have been used for validation/verification of numerical results.


1996 ◽  
Vol 31 (1) ◽  
pp. 9-24 ◽  
Author(s):  
S J Hardy ◽  
M K Pipelzadeh

This paper describes the results of a study of the elastic–plastic behaviour of short flat bars with projections subjected to monotonic and cyclic shear loading using finite element analysis. Six geometries, associated with both local and remote restraints (resulting in elastic stress concentration factors in the range 1.90–7.20), are considered. Three simple bilinear elastic–plastic material models are assumed. The results have been normalized with respect to material properties so that they can be applied to geometrically similar components made from other materials which can be represented by the same materials models.


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