Piping Systems Research Articles

Best clinical practice experience at University of Gondar Comprehensive specialized Hospital Emergency and critical care Medicine department, A Case Study Under a resource limited set up

Abstract Background The emergency department (ED) is unique unstable environment where someone faces unscheduled and undifferentiated diseased patients, stressed families, unsettled staffs and unequitable resources.UoGCSH is the oldest in the Ethiopia and the only referral hospital for more than 13 million people from the five-zone north-west Ethiopia with 950 beds capacity. During the 2020 G.C a proposal paper was submitted to the administration bodies of the college and the hospital. The proposal was suggesting short term, mid-term and long-term quality improvement segments implemented in institutionally convenient manner. Objective To describe the transformation of emergency and critical care medical services at University of Gondar Comprehensive specialized hospital from scratch to the current status. Method A descriptive case study design was applied to narrate critical care service transformation at UoG Comprehensive Specialized Hospital. Since this case study is a data review from gathered secondary data, desk reviews of the emergency department, quality directorate data review, and the annual audit report review, there was no need for IRB approval. Result and recommendation After a year of renovation, we were able to organize a newly refurbished emergency room having a triage area with adequate reception space, Red resuscitation area with 10 beds (considering patient overflow), Orange with 18 beds, Yellow with 10 beds and floater area, isolation room, decontamination room, ED laboratory, main store, disaster store and piped oxygen system to all beds. we have gone a long journey in bringing those promised practices into demonstrable practice and finally replicable prototypic best practice. Even though we paced extra miles in achieving this status. Standard emergency room work flow implementation enable us to control the day-to-day patient and attendant crowding that impedes the anticipated medical treatment outcome and result in a significant dissatisfaction.Despite this achievement the trauma center establishment and high-quality patient care is recommended.

Research on digital vibration model of typical components in pipe system

The spatial distribution of pipe system is complex, long span and multi-point elastic support, so vibration analysis of pipe system is required in the pipeline design. This paper takes the pipe system as a typical component, based on the Timoshenko beam model, establishes a dynamic procedure for straight pipe elements that considers the axial flow rate of fluid, the pressure on the pipe wall, the Poisson coupling effect of fluid and pipeline structure, and the axial, transverse and torsional vibration. Through Laplace transform, the frequency simplified dynamic model is established. And the frequency transfer matrix model of straight pipe elements and the boundary constraint matrix of common boundary (such as fixed support) is established. Finally, the frequency domain transfer matrix model of different pipeline elements are set to the overall transfer matrix of the flow pipe system, providing a convenient means for rapid optimization of pipe system vibration.

Vibration analysis of piping system coupled with conical-cylindrical combined shells

Fluid-filled piping system are widely used in power cooling, fuel transportation and underwater vessel, which not only produce vibration along the system, but also transmit to the connecting structure to generate noise in ambient environment. Most investigations have concentrated on either the vibration characteristics of piping systems or of combined shells separately. In this work, an analytical impedance synthesis method (ISM) is proposed to analyze the vibration characteristics of a pipe-hull coupled system, in which the hull can be simplified to a combined conical-stiffened cylindrical-hemisphere shell. The piping system is modeled by fluid-filled beams in three-dimensional configuration. Wave function and power series solution are used to describe the displacements of cylindrical and conical shell respectively. Based on exact analytical solutions, the impedance matrix of each segment is established separately and assembled in the global coordinate by displacement continuity and force balance boundary conditions. Forced responses are compared with the experimental results to verify the correctness of the method.

Insertion loss of pipe clamps: Quantity for prediction or manufacturer's advertising?

The noise emitted by water conveying pipes as part of sanitary installations is, in most cases, dominated by structure-borne sound transmission. The water flowing through the pipe causes a vibration of the pipe system that is transmitted to the installation wall through pipe clamps. A common mitigation measure is an elastic inlay inside the pipe clamps. Some manufacturers of these clamps advertise the insertion losses determined by non-standardized tests. Recent studies show a high dependency of the insertion loss on the mounting conditions, e.g. how tight are pipes fastened in the clamp. This contribution aims to answer the question of whether and how the mounting condition affects the insertion loss of the pipe clamps and thus how representative the specified values can be for the building situation. The investigations are carried out in-situ on the reception plate and in a building like test stand with an excitation by flowing water as well as with impact hammer excitation. This study is part of a research project with the overall aim to provide source data for the prediction of the sound transmission in buildings using EN 12354-5.

Comparative study of flame propagation characteristics of methane explosion in pipeline with different venting structures at different ignition positions

The effect of central ignition and four types of explosion vents (circular vents with areas of 22.89, 15.20, and 9.07 cm2 and a cross-shaped vent with an area of 15.20 cm2) on the flame propagation of methane explosions was investigated by using a rectangular blast pipe system and analyzed in comparison with the closed-end ignition condition. Central ignition shows that the flame propagation velocity on both sides of the pipe increases and decreases. The peak pressure decreases as the vent area increases. Specifically, Pm (9.07 cm2) > Pm (15.20 cm2) > Pm (22.89 cm2). The flame temperature at the closed end was consistently higher than that at the vented end. The vm values in the closed-end ignition pipe increased by 20.0 %, 41.8 %, 45.8 %, 40.9 %, 31.5 %, and 19.0 %, respectively, over the central ignition position when the methane concentration was 8–13 %. When the methane concentration deviates from the stoichiometric ratio, the difference in peak pressure between closed-end and central ignition can be up to 0.15 MPa, which is 26.7 % of that of central ignition. The peak temperatures observed at points 1–2 in the closed-end ignition were consistently higher than the central ignition.

Defect characterization from magnetic field leakage signals in petroleum and natural gas pipelines

Pipelines transport invaluable energy resources such as crude oil and natural gas over long distances. The integrity of the piping system in terms of safety of the process is then of high importance. However, pipes are prone by time to defects that may degrade their properties and lead to failures. In this paper, we study the effect of defect parameters on the magnetic field leakage captured by Hall sensors operating along the pipe. In fact, the obtained results show that the defect parameters influence directly the MFL amplitude and shape. For this reason, the inversion problem allowing us to reconstruct the defect from the MFL signals became fast and easier in comparison to the deterministic and probabilistic algorithm inversion procedure. However, the simplified system cannot describe the real defects and the three-dimensional numerical study became necessary. In tank floor inspection domain, as our recent published work, we have studied the performance of defect shape reconstruction from MFL array sensor imaging and depth estimation while using an iterative inversion method. Indeed, the first stage consists of determining the defect width and length from magnetic flux leakage mapping reconstructed from the recorded signals of the micro-integrated magnetic sensors. Then, after coupling Comsol and Matlab software, the defect depth is obtained by coupling the 3D finite elements method and a fast iterative algorithm recently developed. Consequently, the defect shape and size are obtained after a few iterations with high precision. Furthermore, this method of defect reconstruction and seizing can be extended for irregular defect shapes encountered in pipeline such as cracks and corrosion.

Quantifying the tangential oscillation of thermal stratification by using principal component analysis

Tangential oscillation of thermal stratification is a new finding in previous investigations on thermal-mixing process at pipeline T-junctions. This phenomenon can create regular temperature changes on the pipeline inner surface and lead to material damage caused by the degradation mechanism of thermal fatigue, which has been frequently reported as a reason for incidents in piping systems of nuclear power plants. Previous investigations cannot provide a quantitative description of this phenomenon, making it difficult to understand or evaluate the fatigue potential due to this phenomenon. In this study, a new method namely principal component analysis has been employed for quantitatively estimating the angular shift of the thermal stratification in pipe tangential direction. Time-dependent angular shift is extracted from the temperature data of the transient simulations of the pipe flow and confirms the initiation of the tangential oscillation of thermal stratification. Moreover, a characteristic frequency of approximately 2.3 Hz has been identified from the frequency spectrum of the time-dependent angular shift. It indicates a potential risk in the piping material due to thermal fatigue. Furthermore, results of this study show a high efficiency and accuracy of the principal component analysis method in quantifying tangential oscillation. It can be applied in further investigations of similar phenomena of thermal stratification.

Dynamic analysis of whipping behavior induced by the circumferential fracture of high energy pipes considering fluid-structure interaction effect

To analyze the dynamic characteristics of whipping behavior induced by the circumferential fracture of high energy pipes, a numerical model of the piping system was presented based on the bidirectional fluid-structure interaction method. The reliability of this model was validated against experimental results. Furthermore, the dynamic characteristics of whipping behavior were studied, as well as the effects of some main parameters. The numerical results suggest that the entire whipping behavior can be divided into four stages: free-whipping stage Ⅰ, free-whipping stage Ⅱ, collision stage and periodic stage. The dynamic response of whipping behavior is different in the four stages and is dominated by a single mode with a frequency of 29.35 Hz under the combined action of the thrust force and U-bolt restraints. The increase of inlet flow rate causes the enhancement of thrust force and thus makes its dynamic response more complicated. The parameter analysis shows that the whipping behavior can be suppressed by choosing the small initial clearance, setting the suitable gap and increasing the straight segment length of U-bolt restraints. The above results are helpful to understand the dynamic characteristics of whipping behavior and provide valuable suggestions for the optimization of the protection measures.

A numerical assessment of different geometries for reducing elbow erosion during pneumatic conveying

This paper investigates wear characteristics in a dilute phase pneumatic conveying pipe system using a Euler-Lagrange method. Simulations couple computational fluid dynamics (CFD) with the discrete element method (DEM) to analyze three different bend geometries, including two erosion-reducing designs and a standard bend, all with an effective bend radius to pipe diameter ratio (R/D) of 1.5. SiO2 particles, 1 mm in diameter, are conveyed at gas velocities of 15 to 30 m/s and mass loadings of 1 to 4 kgparticle/kggas. The CFD-DEM predictions were validated against experimental data, showing good agreement in erosion distribution. The study evaluates erosion rates, pressure drops, and particle stressing for the three bends. Results suggest that certain bend designs significantly reduce erosion while slightly increasing pressure drop, although reduced particle-wall erosion may increase the overall particle stressing. The obtained results provide guidance on selecting an appropriate bend design and for potential geometry optimizations.

Attenuation properties of a meta-pipe: Analytical, experimental, and numerical prediction

Flexural vibration characteristics of a meta-pipe are investigated in this paper. Initially, the metamaterial piping system consisting of a homogeneous pipe and periodic flexible supports is designed. Subsequently, the dispersion relationship which is a function of the wavenumber and the frequency is derived employing the transfer matrix method and Bloch’s theorem. The designed system reveals a zero-frequency stopband and a wide passband in the examined frequency range, which are verified by both experimental and numerical results. To enhance the performance of this system, it is essential to effectively control the obtained passband. For this, a single-degree-of-freedom localized resonator is designed, which is subsequently installed at the center of each unit-cell of the pipe. The dispersion properties of this system are first evaluated analytically and then validated using experimental and numerical methods. Finally, the effect of pipe system parameters and resonator properties on the stopband characteristics is studied in depth. It was observed that the stopband properties can be effectively tuned by appropriately designing the piping system and resonators. The results presented in this study offer valuable insights into the propagation characteristics of flexural waves and the strategies devised for controlling vibrations in pipes.

Development and Design Validation of an Inflow-Settling Chamber for Turbomachinery Test-Benches

At Leibniz University of Hannover, Germany, a new turbomachinery test facility has been built over the last few years. A major part of this facility is a new 6 MW compressor station, which is connected to a large piping system, both designed and built by AERZEN. This system provides air supply to several wind tunnel and turbomachinery test rigs, e.g., axial turbines and axial compressors. These test rigs are designed to conduct high-quality aerodynamic, aeroelastic, and aeroacoustic measurements to increase physical understanding of steady and unsteady effects in turbomachines. One primary purpose of these investigations is the validation of aerodynamic and aeroacoustic numerical methods. To provide precise boundary conditions for the validation process, extremely high homogeneity of the inflow to the investigated experimental setup is imminent. Thus, customized settling chambers have been developed using analytical and numerical design methods. The authors have chosen to follow basic aerodynamic design steps, using analytical assumptions for the inlet section, the “mixing” area of a settling chamber, and the outlet nozzle in combination with state-of-the-art numerical investigations. In early 2020, the first settling chamber was brought into operation for the acceptance tests. In order to collect high-resolution flow field data during the tests, Leibniz University and AERZEN have designed a unique measurement device for robust and fast in-line flow field measurements. For this measurement device, total pressure and total-temperature rake probes, as well as traversing multi-hole probes, have been used in combination to receive high-resolution flow field data at the outlet section of the settling chamber. The paper provides information about the design process of the settling chamber, the developed measurement device, and measurement data gained from the acceptance tests.

Innovative Approaches to Expansion Loop Design for Enhanced Piping System Durability

Expansion loops are critical components in piping systems, designed to manage stress caused by thermal expansion and contraction, thereby ensuring the system's durability and safety. This study investigates innovative approaches to optimizing expansion loop design, focusing on improving the performance and reliability of piping systems under various operational conditions. The research examines multiple configurations, including alterations in loop length, shape modifications, and the incorporation of additional loops, to assess their impact on stress distribution within the system. While the primary focus of this study is on static stress analysis, transient operational factors, such as water hammer, were also considered in the analysis to provide a more comprehensive understanding of the loop configurations' performance under various conditions. The findings demonstrate that while increasing the loop length can effectively reduce stress, alternative designs, such as double loops or modified shapes, offer superior stress management, particularly in space-constrained environments. The study concludes that optimal expansion loop design should accommodate thermal expansion and provide robustness against potential transient effects, contributing to a more reliable piping system. These insights provide valuable guidelines for the design and optimization of piping systems across various industrial applications.

Dynamic Responses in a Pipe Surrounded by Compacted Soil Suffering from Water Hammer with Fluid–Structure–Soil Interactions

The current literature analyzing the dynamic response of coupled pipelines neglects the crucial interplay between the pipelines themselves and these constraints. This overlooked interaction has substantial influence on the fluid–structure coupling response, particularly in scenarios involving continuous constraints. We focus on a piping system surrounded by compacted soil, which is regarded as unbounded homogeneous elastic soil that suffers from water hammer. This study established a one-dimensional model for water pipe-embedded compacted soil with fluid–structure–soil interaction. Taking fluid–structure–soil interaction into account, fluid–structure interactions (FSIs) include Poisson coupling, junction coupling emerging at the fluid–structure interface, and pipe–soil coupling (PSC) emerging at the pipe–soil interface. In this study, as soil is assumed to be a homogeneous, isotropic elastic material, the coupling responses are more complex than those of an exposed pipe, and the relevant mechanisms justify further exploration to obtain well-predicted results. To mathematically describe this system considering fluid–structure–soil interaction, the four-equation FSI model was modified to accommodate the piping system surrounded by unbounded homogeneous elastic soil, employing the finite volume method (FVM) as a means to tackle and solve the dynamic problems with FSI and PSC, which partitions the computational domain into a finite number of control volumes and discretizes governing equations within each volume. The results were validated by the experimental and numerical results. Then, dynamic FSI responses to water hammer were studied in a reservoir–pipe–reservoir physical system. The hydraulic pressure, pipe wall stress, and axial motion were discussed with respect to different parameters. With the PSC and FSI taken into account, fluid, soil, and pipe signals were obviously observed. The results revealed the structural and fluid modes. Dynamic responses have been proven to be difficult to understand and predict. Despite this, this study provides a tractable method to capture more accurate systematic characteristics of a water pipe embedded in soil.

Failure analyses for plate monotonic/cyclic and elbow out-of-plane cyclic loading tests using the Gurson–Tvergaard–Needleman model

In this study, an analytical approach is proposed to simulate the failure behavior of a thinned-wall pipe elbow subjected to internal pressure and out-of-plane cyclic bending loads. This approach incorporates the Gurson–Tvergaard–Needleman model, whose parameters were determined by the plate monotonic tensile test and finite element analyses. The applicability of this analytical approach for low-cycle fatigue failure was confirmed through experiments and simulations. The analytical results captured the failure behavior of the pipe elbow during the out-of-plane cyclic bending test. This finding suggests that the analytical approach can be used for nonlinear deformation evaluation and multiaxial low-cycle fatigue assessment of piping systems.

Analysis of operation regulation on delay time in long-distance heating pipe systems for practical engineering

The distribution area of the district heating network (DHN) is extensive, and there are inherent time delays and thermal losses in the process of heat transfer through heating pipes. The delay in heat transfer within long-distance heating pipes may result in inadequate heat supply to end-users or excessive energy consumption at the heat source. Therefore, this paper presents a quasi-dynamic model for calculating the transmission delay time in the long-distance heating pipeline. And the model is validated through the measured values obtained from a heating pipeline. The influencing factors of delay time are further discussed, including operating parameters, pipe structure parameters and thermal insulator thickness. Additionally, the impact of pipe delay time in practical engineering is analyzed. In practical engineering, the transmission delay time varies when the pipe structural or operational parameters differ, even under the same outdoor temperature change. The change in inlet water temperature and mass flow rate can impact the change rate of outlet water temperature, thereby influencing the delay time. Furthermore, the delay time exhibited an increase with pipe length, diameter, and thermal insulator thickness; however, the effect of thermal insulator thickness on it was minimal. When the inlet water temperature rose or dropped by 5℃, the delay time grew by more 70 % per 1 km pipe length, about 40 % per 100 mm diameter and less 2 % per 100 mm thermal insulator thickness, respectively.

Integrated urban wastewater system operation: Performance evaluation and sewer network's operation implications

ABSTRACT The paper deals with the operation of the Integrated Urban Wastewater System as composed of the Sewer Network and associated Wastewater Treatment Plant. The performance of the integrated system is defined in terms of appropriate, selected, performance indicators of both subsystems. Both subsystems are connected and interact by a piping system. It is shown how the performance of the Integrated Urban Wastewater System is affected by various Sewer Network control scenarios: (1) only the Sewer Network outlet valve opening is controlled, (2) all the Sewer Network valves are controlled by a Model Predictive Control algorithm developed for minimizing the environmental impact of the subsystem and modified by constraining it in terms of Sewer Network outlet valve opening. More specific, it is proven that the Sewer Network outlet valve opening has an important role in the performances of the integrated system, and that already existing Sewer Network control strategies can be altered in such a way that they will enhance these performances.

A comparative study of the potentials of Oman and UAE in condensate water recovery

<p class="MsoNormal" style="text-align: justify; text-justify: inter-ideograph; line-height: 120%; mso-pagination: none; layout-grid-mode: char; mso-layout-grid-align: none; text-autospace: none; margin: 12.0pt 0cm 6.0pt 147.4pt;"><span lang="EN-US" style="font-size: 10.0pt; line-height: 120%; font-family: 'Times New Roman',serif;">Freshwater is essential for everyday activities including drinking, irrigation, farming and many industrial processes. However, freshwater is less than 1% of the total water resources in the planet and, therefore, it is considered a very valuable commodity. Limited resources and growing needs for freshwater triggered global exploration for alternatives to produce enough freshwater for human needs. Today’s most widely used methods to produce freshwater is desalination. However, critical appraisal of the desalination procedures raised the alarm about </span><span lang="EN-GB" style="font-size: 10.0pt; line-height: 120%; font-family: 'Times New Roman',serif; mso-fareast-font-family: 宋体; mso-font-width: 105%; mso-font-kerning: 0pt; mso-ligatures: none; mso-ansi-language: EN-GB;">sustainability</span><span lang="EN-US" style="font-size: 10.0pt; line-height: 120%; font-family: 'Times New Roman',serif;"> of desalination and indicated that significant research is needed to develop alternative green resources of freshwater. Countries in the Gulf area such as Oman and UAE experience hot and humid climates and use air-conditioning units to achieve acceptable comfort levels and create a </span><span lang="EN-GB" style="font-size: 10.0pt; line-height: 120%; font-family: 'Times New Roman',serif; mso-fareast-font-family: 宋体; mso-font-width: 105%; mso-font-kerning: 0pt; mso-ligatures: none; mso-ansi-language: EN-GB;">healthier</span><span lang="EN-US" style="font-size: 10.0pt; line-height: 120%; font-family: 'Times New Roman',serif;"> indoor environment. The cooling process release a large amount of condensate water through cooling coils. This amount of water is usually considered as a problem rather than opportunity and, thus, is wasted into municipal sewerage systems via a system of drainage pipes. This alternative source can be utilized in various drainage, irrigation, and cooling applications to reduce the use of considerable amount of municipal potable water. This source not only takes part in controlling the water scarcity, but also in saving energy and to reducing the carbon footprint. This paper focus on highlighting the opportunities for Oman and UAE to utilize the condensate water from air-conditioning process, as a viable alternative source of green </span><span lang="EN-GB" style="font-size: 10.0pt; line-height: 120%; font-family: 'Times New Roman',serif; mso-fareast-font-family: 宋体; mso-font-width: 105%; mso-font-kerning: 0pt; mso-ligatures: none; mso-ansi-language: EN-GB;">fresh</span><span lang="EN-US" style="font-size: 10.0pt; line-height: 120%; font-family: 'Times New Roman',serif;"> water. It provides a comparison of the potentials of both countries to collect condensate water, based on meteorological data, location and climate. It was concluded that both countries have great potentials and opportunities to utilize this wasted resource. </span></p>

Installation of Clean Water Piping for Resident on Jl. Arjuna, RW 08 and 09, East Labuh Baru, Pekanbaru

Water is a crucial resource for sustaining life; however, access to it through the Regional Drinking Water Company (Indonesian: Perusahaan Daerah Air Minum [PDAM]) remains limited in certain communities. As a result, residents frequently depend on groundwater sourced through independent pumping by households, places of worship, public facilities, private and government offices, and others. An assessment of the buildings on Jl. Arjuna RW 08 and 09, East Labuh Baru District, Pekanbaru, indicates a significant lack of adequate clean water installation systems, highlighting a need for targeted community service efforts. This initiative aims to rectify these deficiencies by drilling wells to establish reliable sources of clean water and installing a comprehensive clean water piping system to ensure effective distribution from the source to the end users, thus aligning with Indonesian National Standards (SNI). The project involves faculty members as part of their commitment to the tri-dharma of higher education, offering both a practical learning opportunity for students and a valuable service to the community.

A review of recent advances and applications of inorganic coating for oil and gas pipe systems

The oil and gas pipe systems are a crucial part of the infrastructure. The structural integrity of pipes is diminishing as a result of environmental damage. In recent years, the oil and gas industry has witnessed significant advancements in the development and application of inorganic coatings for pipeline systems. These coatings are essential for enhancing the durability, safety, and efficiency of pipelines by providing superior resistance to corrosion, abrasion, and chemical attacks. This review paper delves into the latest fabrication strategies for API pipe coatings, with a focus on the electroless method, electrodeposition method, thermal spray method, thermochemical method, and other emerging techniques. Each method is evaluated in terms of its principles, advantages, limitations, and suitability for different operational environments. Among the coating methods, the electroless process is one of the most popular methods. The paper also highlights innovative approaches and materials that have the potential to revolutionize the field. By providing a comprehensive overview of current technologies and their applications, this review aims to guide future research and development efforts, promoting the adoption of advanced inorganic coatings in the oil and gas industry to ensure the longevity and integrity of critical infrastructure.

Elastoplastic limit analysis of functionally graded materials pipe elbows to predict the damage under in-plane bending moment using XFEM-Technic

Functionally Graded Materials (FGMs) have become a vast field of research, due to their wide range of applications and numerous advantages. The use of FGMs has recently expanded, particularly in the reinforcement of tubular structures. Pipe elbows are among the most important elements in a piping system, responsible for reducing stresses and balancing pressure inside pipes. However, due to significant deformations, most frequently caused by bending moment loads, elbows are more prone to exceeding their stress limits. It is for this reason that the analysis of these tubular structures has attracted the interest of many researchers. As a result, the study of their reinforcement can only be carried out through the study of their damage. In other words, to unlock the difficulties of numerically predicting their responses. The aim of our study is to use the finite element method with the proposed meshing technique in the ABAQUS calculation code, to analyze the behavior of a 90° elbow tubular structure, attached to two straight sections, made of functionally graded FGM Al/SiC (Aluminum/Silicon Carbide) material, with a continuous gradual variation of properties in the direction of wall thickness, per row of finished elements along the entire geometry of the tubular structure, in order to simulate a real pipe system installation. The structure is loaded by two modes of in-plane bending moment (Closing and Opening), with an imposed rotational displacement. The aim of this analysis is to evaluate, firstly, the effects of different grading concepts for the FGM Al/SiC material couple in the model geometry (Simple and Symmetrical Concepts), and secondly, the effect of different power exponent indices (n) of the volume fraction, on the elasto-plastic response up to the damage of the tubular structure. The constitutive behavioral law of our model is based on Von Mises’ equivalent stress flow theory with a hardening variable in incremental form. In addition, the TTO (Tamura-Tomota-Ozawa) model was used to describe the elastic-plastic behavior of the FGM, and the XFEM technique was also applied for crack initiation and propagation. The results obtained under moment-rotation conditions show a significant effect on the response as well as on the level of damage, the effect is also remarkable on the ovalization at the bend cross-section. The approach and reliability of the results obtained were based on a comparison with experimental results, which show good agreement, compared with our numerical model.