scholarly journals Cylinder Bore Deformation Finite Element Analysis Methodology for Inline Engines and Parametric Optimization

Cylinder bore deformation plays an important role between piston and cylinder bore. The cylinder bore deformation may happen due to manufacturing process tolerances, assembly loading, thermal loading and dynamic gas loading. It has significant impact on the friction, fuel economy, lubricant oil consumption, reduction in power, increase in emissions, uneven power generation in different cylinders etc. This work proposes FEA analysis procedure that could be used to evaluate the cylinder bore distortion due to assembly (clamping) load of cylinder head bolts. Cylinder bore deformation due to head bolt clamp loading is predicted using FEA analysis package MSC NASTRAN for 3 cylinder inline Diesel engine. The effect of various parameters like effect of increase in pretension force on amount of bore deformation are studied. The predicted results are compared with previous experimental results and fair agreement have been observed.

Actuators ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 81
Author(s):  
Atif Zahid ◽  
Faisal Khan ◽  
Naseer Ahmad ◽  
Irfan Sami ◽  
Wasiq Ullah ◽  
...  

A dual mover yokeless multi-tooth (DMYMT) permanent magnet flux switching motor (PM-FSM) design is presented in this article for ropeless elevator applications. The excitation sources, including a field winding and permanent magnet, are on the short mover in the proposed design structure, whereas the stator is a simple slotted iron core, thus reducing the vertical transportation system cost. The operational principle of the proposed DMYMT in PM-FSM is introduced. The proposed dual mover yokeless multi-tooth Permanent Magnet Flux Switching Motor is analyzed and compared for various performance parameters in a Finite Element Analysis package. The proposed machine has high thrust force and cost-effectiveness compared to conventional dual permanent magnet motor. Finally, this paper also develops an analytical model for the proposed structure, validated by comparing it with Finite Element Analysis simulation results. Results show good agreement between analytical prediction and Finite Element Analysis results.


Author(s):  
Michel Arnal ◽  
Christian Precht ◽  
Thomas Sprunk ◽  
Tobias Danninger ◽  
John Stokes

The present paper outlines a practical methodology for improved virtual prototyping, using as an example, the recently re-engineered, internally-cooled 1st stage blade of a 40 MW industrial gas turbine. Using the full 3-D CAD model of the blade, a CFD simulation that includes the hot gas flow around the blade, conjugate heat transfer from the fluid to the solid at the blade surface, heat conduction through the solid, and the coolant flow in the plenum is performed. The pressure losses through and heat transfer to the cooling channels inside the airfoil are captured with a 1-D code and the 1-D results are linked to the three-dimensional CFD analysis. The resultant three-dimensional temperature distribution through the blade provides the required thermal loading for the subsequent structural finite element analysis. The results of this analysis include the thermo-mechanical stress distribution, which is the basis for blade life assessment.


2014 ◽  
Vol 966-967 ◽  
pp. 175-183 ◽  
Author(s):  
Mohammed Yousfi ◽  
Sabeur Mezghani ◽  
Ibrahim Demirci ◽  
Mohamed El Mansori

The cylinder liner surface texture, widely generated by the honing technique, contributes a lot on engine functional performances (friction, oil consumption, running-in, wear etc.). In order to improve these functional performances, different honing processes are being developed. These different honing processes generate surfaces with various texture features characteristics (roughness, valleys depth, valley width, cross hatch angle, etc.). This paper addresses a comparison of ring-pack friction for cylinder texture with different cross-hatch angles and valley sizes. It takes in consideration the mutual effect of valley depth and honing angle. A numerical model is developed to predict friction within the cylinder ring-pack system in mixed lubrication regime and a morphological method is used to characterize groove depth. The results show the effect of different honing variables (rotation speed, stroke speed and indentation pressure) on cylinder bore surface textures and hydrodynamic friction of the ring-pack system.


Author(s):  
Muhammad Abid ◽  
Javed A. Chattha ◽  
Kamran A. Khan

Performance of a bolted flange joint is characterized mainly by its ‘strength’ and ‘sealing capability’. A number of analytical and experimental studies have been conducted to study these characteristics only under internal pressure loading. In the available published work, thermal behavior of the pipe flange joints is discussed under steady state loading with and without internal pressure and under transient loading condition without internal pressure. The present design codes also do not address the effects of steady state and thermal transient loading on the structural integrity and sealing ability. It is realized that due to the ignorance of any applied transient thermal loading, the optimized performance of the bolted flange joint can not be achieved. In this paper, in order to investigate gasketed joint’s performance i.e. joint strength and sealing capability under combined internal pressure and transient thermal loading, an extensive nonlinear finite element analysis is carried out and its behavior is discussed.


1996 ◽  
Vol 118 (4) ◽  
pp. 206-213 ◽  
Author(s):  
K. X. Hu ◽  
C. P. Yeh ◽  
X. S. Wu ◽  
K. Wyatt

Analysis of interfacial delamination for multichip module thin-film interconnects (MCM/TFI) is the primary objective of this paper. An interface crack model is integrated with finite-element analysis to allow for accurate numerical evaluation of the magnitude and phase angle of the complex stress intensity factor. Under the assumption of quasi-static delamination growth, the fate of an interfacial delamination after inception of propagation is determined. It is established that whether an interfacial delamination will continue to grow or become arrested depends on the functional behavior of the energy release rate and loading phase angle over the history of delamination growth. This functional behavior is numerically obtained for a typical MCM/TFI structure with delamination along die and via base, subjected to thermal loading condition. The effect of delamination interactions on the structural reliability is also investigated. It is observed that the delamination along via wall and polymer thin film can provide a benevolent mechanism to relieve thermal constraints, leading to via stress relaxation.


Author(s):  
Sayed A. Nassar ◽  
Amir Kazemi

Experimental and finite element techniques are used for investigating the effect of cyclic thermal loading on the clamp load decay in preloaded single-lap bolted joints that are made of multimaterial lightweight alloys. Substrate material combinations include aluminum, magnesium, and steel, with various coupon thicknesses. The range of cyclic temperature profile varies between −20 °C and +150 °C in a computer-controlled environmental chamber for generating the desired cyclic temperature profile and durations. Real time clamp load data are recorded using strain gage-based, high-temperature, load cells. Clamp load decay is investigated for various combinations of joint materials, initial preload level, and substrate thickness. Thermal and material creep finite element analysis (FEA) is performed using temperature-dependent mechanical properties. The FEA model and results provided a valuable insight into the experimental results regarding the vulnerability of some lightweight materials to significant material creep at higher temperatures.


1998 ◽  
Vol 33 (1) ◽  
pp. 55-65 ◽  
Author(s):  
J Lin ◽  
F P E Dunne ◽  
D R Hayhurst

An approximate method has been presented for the design analysis of engineering components subjected to combined cyclic thermal and mechanical loading. The method is based on the discretization of components using multibar modelling which enables the effects of stress redistribution to be included as creep and cyclic plasticity damage evolves. Cycle jumping methods have also been presented which extend previous methods to handle problems in which incremental plastic straining (ratchetting) occurs. Cycle jumping leads to considerable reductions in computer CPU (central processing unit) resources, and this has been shown for a range of loading conditions. The cycle jumping technique has been utilized to analyse the ratchetting behaviour of a multibar structure selected to model geometrical and thermomechanical effects typically encountered in practical design situations. The method has been used to predict the behaviour of a component when subjected to cyclic thermal loading, and the results compared with those obtained from detailed finite element analysis. The method is also used to analyse the same component when subjected to constant mechanical loading, in addition to cyclic thermal loading leading to ratchetting. The important features of the two analyses are then compared. In this way, the multibar modelling is shown to enable the computationally efficient analysis of engineering components.


1999 ◽  
Vol 122 (2) ◽  
pp. 121-127 ◽  
Author(s):  
Manjula N. Variyam ◽  
Weidong Xie ◽  
Suresh K. Sitaraman

Components in electronic packaging structures are of different dimensions and are made of dissimilar materials that typically have time, temperature, and direction-dependent thermo-mechanical properties. Due to the complexity in geometry, material behavior, and thermal loading patterns, finite-element analysis (FEA) is often used to study the thermo-mechanical behavior of electronic packaging structures. For computational reasons, researchers often use two-dimensional (2D) models instead of three-dimensional (3D) models. Although 2D models are computationally efficient, they could provide misleading results, particularly under thermal loading. The focus of this paper is to compare the results from various 2D, 3D, and generalized plane-deformation strip models and recommend a suitable modeling procedure. Particular emphasis is placed to understand how the third-direction coefficient of thermal expansion (CTE) influences the warpage and the stress results predicted by 2D models under thermal loading. It is seen that the generalized plane-deformation strip models are the best compromise between the 2D and 3D models. Suitable analytical formulations have also been developed to corroborate the findings from the study. [S1043-7398(00)01402-X]


2021 ◽  
Author(s):  
CHAIANE WIGGERS DE SOUZA ◽  
MOONHEE NAM ◽  
HYONNY KIM

Large test structures, common in the aerospace industry, offer a challenge to model, manufacture and test, with high cost associated with computational as well as materials, specimen fabrication, test planning/setup, and instrumentation resources. In this paper, a methodology is presented to demonstrate use of a smaller-sized substructure to produce equivalent response to the original, larger structure. The structure under study is a quarter barrel of typical commercial aircraft fuselage section made of carbon fiber reinforced polymer (CFRP), initially consisting of two circumferential structural members (C-frames and shear ties), and 12 stringers cocured to the skin. Through a series of finite element analyses and a modified specimen design, a substructure representing the quarter barrel was validated for loading conditions generated by high energy wide area blunt impacts (HEWABI) which are potentially caused by accidental contact from moving ground service equipment (GSE). The substructure is made of one circumferential member (C-frame and shear tie), and 6 stringers co-cured to skin and is shown to have similar stiffness and stresses in the region of interest. Finite element analysis (FEA) with progressive damage analysis demonstrates the equivalent response between the substructure and full quarter barrel. This methodology can be used in a wide range of applications, as long as the loading area is distant enough from the modified structure end and the correct boundary conditions/fixtures are defined to represent the omitted portions of the structure of interest.


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