Optimum design of structures with multiple frequency constraints using the finite element force method

The optimum design of rotating laminated blade subject to dynamic behavior constraint is investigated. The dynamic behavior constraints consist of restrictions on multiple natural frequencies as well as on maximum dynamic deflections of rotating laminated blade. The harmonic excitations are considered to simulate the aerodynamic forces acting on the blade. The optimization techniques of optimality criterion method and modified method of feasible directions have been successfully developed and applied to minimize the weight of rotating laminated blade. The effect of setting angles and rotating speed on the system dynamic behaviors as well as on the optimum design are also studied. The dynamic analysis shows that most of the bending modes can be significantly affected by rotating speed, setting angle, and the radius of disc. The results also indicate that the optimum weight will decrease with the increase of rotating speed for the multiple frequency constraints. The similar phenomena is also obtained for the dynamic response constraints. Moreover, the optimum weight of the dynamic response constraints case is higher than that of multiple frequency constraints case. This study presents that the weight of rotating laminated blade can be greatly reduced at optimum stage.

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Optimum design and validation of flat composite beams dubject to frequency constraints

AIAA Journal ◽

10.2514/3.13537 ◽

1997 ◽

Vol 35 ◽

pp. 540-545

Author(s):

J. M. Taylor ◽

R. Butler

Keyword(s):

Optimum Design ◽

Composite Beams ◽

Frequency Constraints

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Analisis Kegagalan Boom Crane dan Pencegahannya

Jurnal Ilmiah Poli Rekayasa ◽

10.30630/jipr.10.1.54 ◽

2014 ◽

Vol 10 (1) ◽

pp. 19

Author(s):

Elvis Adril ◽

Nasirwan - ◽

Tri Wibowo ◽

Julnaidi -

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Chemical Composition ◽

Optimum Design ◽

Root Cause ◽

Main Equipment ◽

Hardness Tests ◽

Photo Documentation ◽

Crawler Crane ◽

Boom Crane

Sleeve (Boom) on Crawler Crane is the main equipment that serves the weight at the time of appointment (Hoisting).The problem which is founded is a fracture at the boom while lift 6 Tons of weight while the optimum design of equipment is 50 tons. The aim of this research is to found the root cause of the fracture by using photo documentation fractografi (microfractografi and macrofractografi), and hardness tests, and test the chemical composition at the surface faults boom crane. We used Finite element method (FEM) to form simulated load. The results is that the porblem accured because of error while read the load chart and error in SOP

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Weighted superposition attraction-repulsion (WSAR) algorithm for truss optimization with multiple frequency constraints

Structures ◽

10.1016/j.istruc.2021.01.017 ◽

2021 ◽

Vol 30 ◽

pp. 253-264

Author(s):

Adil Baykasoğlu ◽

Cengiz Baykasoğlu

Keyword(s):

Truss Optimization ◽

Multiple Frequency ◽

Frequency Constraints

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An enhanced symbiotic organisms search algorithm for design optimization of trusses with frequency constraints

Advances in Structural Engineering ◽

10.1177/13694332211026219 ◽

2021 ◽

pp. 136943322110262

Author(s):

Mohammad H Makiabadi ◽

Mahmoud R Maheri

Keyword(s):

Standard Deviation ◽

Optimization Problems ◽

Search Algorithm ◽

Metaheuristic Algorithms ◽

Minimum Mass ◽

Multiple Frequency ◽

Frequency Constraints ◽

Symbiotic Organisms Search ◽

Symbiotic Organisms ◽

Dynamic Frequency

An enhanced symbiotic organisms search (ESOS) algorithm is developed and presented. Modifications to the basic symbiotic organisms search algorithm are carried out in all three phases of the algorithm with the aim of balancing the exploitation and exploration capabilities of the algorithm. To verify validity and capability of the ESOS algorithm in solving general optimization problems, the CEC2014 set of 22 benchmark functions is first optimized and the results are compared with other metaheuristic algorithms. The ESOS algorithm is then used to optimize the sizing and shape of five benchmark trusses with multiple frequency constraints. The best (minimum) mass, mean mass, standard deviation of the mass, total number of function evaluations, and the values of frequency constraints are then compared with those of a number of other metaheuristic solutions available in the literature. It is shown that the proposed ESOS algorithm is generally more efficient in optimizing the shape and sizing of trusses with dynamic frequency constraints compared to other reported metaheuristic algorithms, including the basic symbiotic organisms search and its other recently proposed improved variants such as the improved symbiotic organisms search algorithm (ISOS) and modified symbiotic organisms search algorithm (MSOS).

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Optimization of the Wrist Pin End of an Automobile Engine Connecting Rod With an Interference Fit

Journal of Mechanical Design ◽

10.1115/1.2912622 ◽

1990 ◽

Vol 112 (3) ◽

pp. 406-412 ◽

Cited By ~ 7

Author(s):

Vijay Sarihan ◽

Ji Oh Song

Keyword(s):

Finite Element ◽

Optimum Design ◽

Three Dimensional ◽

Stress Singularity ◽

Design Strategy ◽

Structural Components ◽

Connecting Rod ◽

Fem Model ◽

Automobile Engine ◽

Interference Fit

Current design procedures for complicated three-dimensional structural components with component interactions may not necessarily result in optimum designs. The wrist pin end design of the connecting rod with an interference fit is governed by the stress singularity in the region where the wrist pin breaks contact with the connecting rod. Similar problems occur in a wide variety of structural components which involve interference fits. For a better understanding of the problems associated with obtaining optimum designs for this important class of structural interaction only the design problems associated with the wrist pin end of the rod are addressed in this study. This paper demonstrates a procedure for designing a functional and minimum weight wrist pin end of an automobile engine connecting rod with an interference fit wrist pin. Current procedures for Finite Element Method (FEM) model generation in complicated three-dimensional components are very time consuming especially in the presence of stress singularities. Furthermore the iterative nature of the design process makes the process of developing an optimum design very expensive. This design procedure uses a generic modeler to generate the FEM model based on the values of the design variables. It uses the NASTRAN finite element program for structural analysis. A stress concentration factor approach is used to obtain realistic stresses in the region of the stress singularity. For optimization, the approximate optimization strategy in the COPES/CONMIN program is used to generate an approximate design surface, determine the design sensitivities for constrained function minimization and obtain the optimum design. This proposed design strategy is fully automated and requires only an initial design to generate the optimum design. It does not require analysis code modifications to compute the design sensitivities and requires very few costly NASTRAN analyses. The connecting rod design problem was solved as an eight design variable problem with five constraints. A weight reduction of nearly 27 percent was achieved over an existing design and required only thirteen NASTRAN analyses. It is felt that this design strategy can be effectively used in an engineering environment to generate optimum designs of complicated three-dimensional components.

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