Multidisciplinary Design Optimization Model Research Articles

Multidisciplinary Design Optimization of Alignment and Whirling Vibration Characteristics of a Submarine Propulsion Shafting Using Kriging Surrogate Model

To improve the performance indexes, such as safety, reliability and acoustic stealth, of a submarine, it is significant to optimize the dynamic characteristics of its propulsion shafting. The alignment state of a shafting has a coupling effect on its whirling vibration characteristics, and the multidisciplinary design optimization (MDO) theory can fully consider the coupling relationships between different disciplines like this, which is a scientific and effective method to achieve the design optimization of shafting dynamics. However, the iterative calculation of high-precision numerical models greatly restricts the optimization efficiency of this method. Aiming at this problem, in this paper, an MDO model was established based on the coupling dynamic analysis of submarine propulsion shafting, and the Kriging surrogate model was used to predict the state variables within each subdiscipline. Along with the reduction of computational expense, the MDO of the alignment and whirling vibration characteristics of the shafting was achieved. The studied results can be applied to the design process of submarine propulsion shafting, which can provide technical and theoretical support for improving the optimization efficiency of its coupling dynamics.

A novel conceptual design method for aviation PMSG based on thermal modeling

A multi-disciplinary optimization design method for permanent magnet synchronous generators based on thermal modeling is proposed in this paper. The complex coupling among the thermal, electromagnetic, and mechanical systems and the difficulties in optimization with conflicting objectives of multiple disciplines has been studied. Firstly, a multi-disciplinary design optimization model is established based on the coupling relationships between the thermal, electromagnetic, and mechanical performance of permanent magnet synchronous generators. Then, optimization objectives are set as low temperature-rise, low volume and weight, and sizeable electromagnetic size. The critical parameters in the thermal, electromagnetic, and mechanical systems of the generators are considered decision variables. The particle swarm optimization algorithm is selected as a multi-objective problem-solving algorithm to support the multi-disciplinary optimization of thermal motor design. Based on thermal modeling, a high disciplinary coupling and high physical fidelity concept design method for aerospace permanent magnet synchronous generators is presented. This conceptual design method can effectively reduce the design cost of aerospace generators, shorten the development cycle, and promote the design and development of aerospace permanent magnet generators.

Multidisciplinary design optimization of vehicle chassis product family

In order to improve the performance of automotive product platforms and product families while keeping high development efficiency, a product family optimization design method that combines shared variable decision-making and multidisciplinary design optimization (MDO) is proposed. First, the basic concepts related to product family design optimization were clarified. Then, the mathematical description and MDO model of the product family optimization problem were established, and the improved product family design process was given. Finally, for the chassis product family optimization problem of an automotive product platform, the effectiveness of the proposed optimization method, and design process were exemplified. The results show that the collaboratively optimized product family can effectively handle the coordination between multiple products and multiple targets, compared to Non-platform development, it can maximize the generalization rate of vehicle parts and components under the premise of ensuring key performance, and give full play to the advantages of product platforms.

Coupling characteristic analysis of ship shafting design parameters and research on multidisciplinary design optimization

In the design process of traditional ship shafting, the design quality is generally hard to get guaranteed for the lack of discipline coupling. In this paper, Multidisciplinary Design Optimization (MDO) is innovatively introduced to ensure design quality. Multidisciplinary decomposition of shafting can help to construct the MDO model of ship shafting based on multidisciplinary feasibility method. Then the sub-discipline model of shifting design can be further established, including calibration neutron discipline model, whirling vibration model, and dynamic stiffness of radial oil film bearing model. Collaborative operation is implemented by the multidisciplinary model of shifting to obtain the experimental results. Based on Radial Basis Function (RBF) neural network, the responsive surfaces of variable, bearing load, and support stiffness can be constructed, in the meanwhile the dynamic stiffness decoupling of vibration model can be obtained. Fireworks algorithm is used to establish multidisciplinary optimization of seven-dimensional design variable. The results show that MDO helps improve the quality of shafting alignment and whirling vibration. The work in present paper also provides insight for the future optimization of research methods, design quality, and engineering experiments.

Efficient strategy for reliability-based optimization design of multidisciplinary coupled system with interval parameters

• The uncertainty propagation method in multidisciplinary system based on subinterval theory is presented. • The interval reliability displacement based multidisciplinary design optimization methodology is proposed. • The partial gradient region for interval reliability is converted to full gradient region for reliability displacement. • The convergence process can be accelerated by utilizing the gradient optimization algorithms. Non-probabilistic reliability based multidisciplinary design optimization has been widely acknowledged as an advanced methodology for complex system design when the data is insufficient. In this work, the uncertainty propagation analysis method in multidisciplinary system based on subinterval theory is firstly studied to obtain the uncertain responses. Then, based on the non-probabilistic set theory, the interval reliability based multidisciplinary design optimization model is established. Considering that the gradient information of interval reliability cannot be acquired in the whole design domain, which causes convergence difficulties and prohibitive computation, an interval reliability displacement based multidisciplinary design optimization method is proposed to address the issue. In the proposed method, the interval reliability displacement is introduced to measure the degree of interval reliability. By doing so, not only the connotation of the interval reliability is guaranteed, but more importantly, the partial gradient region for interval reliability is equivalently converted into full gradient region for reliability displacement. Consequently, the gradient information can be acquired under any circumstances and thus the convergence process is highly accelerated by utilizing the gradient optimization algorithms.

Multidisciplinary design optimization of sandwich-structured radomes

A multidisciplinary design optimization framework is proposed for sandwich-structured radomes. Radomes ensure the functional operation of antenna systems in adverse environment catering for aerodynamic stresses and payload requirements. The existence of radomes can partially degrade the electromagnetic performance of antenna systems. The electromagnetic performance and mechanical responses are taken into account simultaneously in the optimization design. This is more time-saving and economical compared to the traditional separate considerations on these two aspects. Coupled with multi-island genetic algorithm, transmission coefficient and boresight error are identified as the objectives. Lateral deformation, material failure, and structural stability are included in mechanical analysis. Three-dimensional ray-tracing technique and physical optics based aperture integration method are employed to address interactions between the antenna and radome. Tsai–Wu and maximum stress criteria are used to predict material failure. Structural stability is analyzed using the linear perturbation of stiffness matrices. The applicability of the electromagnetic model is validated using examples of a hemispheric air and single-layered radome. A numerical experiment is conducted to investigate the utility and feasibility of the multidisciplinary design optimization model. Results show that the optimal section profile brings about considerable improvement in transmission coefficient and boresight error. Mechanical constrains are reasonably subjected to the preset limits. Hence, the proposed multidisciplinary design optimization model is an effective and feasible alternative in the environment of radome design.

Multidisciplinary design optimization of hard rock tunnel boring machine using collaborative optimization

A multidisciplinary design optimization model is developed in this article to optimize the performance of the hard rock tunnel boring machine using the collaborative optimization architecture. Tunnel boring machine is a complex engineering equipment with many subsystems coupled. In the established multidisciplinary design optimization process of this article, four subsystems are taken into account, which belong to different sub-disciplines/subsytems: the cutterhead system, the thrust system, the cutterhead driving system, and the economic model. The technology models of tunnel boring machine’s subsystems are build and the optimization objective of the multidisciplinary design optimization is to minimize the construction period from the system level of the hard rock tunnel boring machine. To further analyze the established multidisciplinary design optimization, the correlation between the design variables and the tunnel boring machine’s performance is also explored. Results indicate that the multidisciplinary design optimization process has significantly improved the performance of the tunnel boring machine. Based on the optimization results, another two excavating processes under different geological conditions are also optimized complementally using the collaborative optimization architecture, and the corresponding optimum performance of the hard rock tunnel boring machine, such as the cost and energy consumption, is compared and analysed. Results demonstrate that the proposed multidisciplinary design optimization method for tunnel boring machine is reliable and flexible while dealing with different geological conditions in practical engineering.

Multi-Disciplinary Design Optimization of Mixed-Use Structure and Energy Performance

Abstract Multi-Disciplinary Design Optimization (MDO) is a research methodology that has been applied in engineering fields to design and evaluate decisions from multiple professions using objective function. However, the application of the MDO model to the field of Urban Design is rare. This paper addresses problems of energy performance of varying Mixed Land Use structures in the context of aspatial distribution. Through the identification of objective factors, which allow for quantification of the multi-layered problem of land use distribution, MDO can be used to derive a Pareto front that can be used to limit the design decision space or choices of future designs. The data needs for the MDO process are intensive and require a high level of contextualization for the best outcomes. The MDO models test options of design decisions through constructing the relationship between the mixed-use ratio and building energy performance at the urban scale. Preliminary findings of mixed-use optimization using aspatial parameters are discussed to better understand this relationship.

Multi-physics Field Analysis of Nuclear Power Valve based on MDO Model

In order to construct the characteristics evaluation system of nuclear power valves, multiphysics analysis (including structural static analysis, thermal-mechanical coupling analysis, flow field analysis and Seismic analysis) are completed on a typical nuclear power valve based on finite element analysis (FEA). Binding the load standard of ASEM, each performance index of the nuclear power valve is tested and forecasted in order to verify the safety performance. Meanwhile, in view of the demands in multidisciplinary design optimization (MDO) of nuclear power valve products, the MDO model for valves is established, which integrates multi-characteristic simulation and multidisciplinary design of nuclear power valves together. The validity of the analysis method above is verified by the valve strength and sealing tests, which is of certain guiding significance for other class of nuclear power valves.

Design and Optimization of Dual-Redundancy Transmission System

According to the special requirements of the redundant input drive system in the aerospace field, a scheme of dual-redundancy transmission system is presented and it meets the requirements that one axis can output movements no matter two input axes are working together or working alone. Based on the analysis of the scheme, structure design scheme is presented, and the matching relationship of gear teeth is derived to meet the requirement of transmission ratio. Then the multidisciplinary design optimization model of the dual-redundancy transmission system is established, in which the system is discomposed into two subsystems: differential gear train and fixed axis gear train. The multidisciplinary variable couple design optimization method of discrete variable is used in the optimal design of dual-redundancy transmission system and the optimal comprehensive scheme is obtained.

Multidisciplinary design optimization on production scale of underground metal mine

In order to ensure overall optimization of the underground metal mine production scale, multidisciplinary design optimization model of production scale which covers the subsystem objective function of income of production, safety and environmental impact in the underground metal mine was established by using multidisciplinary design optimization method. The coupling effects from various disciplines were fully considered, and adaptive mutative scale chaos immunization optimization algorithm was adopted to solve multidisciplinary design optimization model of underground metal mine production scale. Practical results show that multidisciplinary design optimization on production scale of an underground lead and zinc mine reflect the actual operating conditions more realistically, the production scale is about 1.25 Mt/a (Lead and zinc metal content of 160 000 t/a), the economic life is approximately 14 a, corresponding coefficient of production profits can be increased to 15.13%, safety factor can be increased to 5.4% and environmental impact coefficient can be reduced by 9.52%.

Multidisciplinary design optimization for air-condition production system based on multi-agent technique

In order to guarantee the overall production performance of the multiple departments in an air-condition production industry, multidisciplinary design optimization model for production system is established based on the multi-agent technology. Local operation models for departments of plan, marketing, sales, purchasing, as well as production and warehouse are formulated into individual agents, and their respective local objectives are collectively formulated into a multi-objective optimization problem. Considering the coupling effects among the correlated agents, the optimization process is carried out based on self-adaptive chaos immune optimization algorithm with mutative scale. The numerical results indicate that the proposed multi-agent optimization model truly reflects the actual situations of the air-condition production system. The proposed multi-agent based multidisciplinary design optimization method can help companies enhance their income ratio and profit by about 33% and 36%, respectively, and reduce the total cost by about 1.8%.

Design and Implementation of MDO Integrated System for Valve Products

In view of the demands in multidisciplinary design optimization (MDO) of valve products, the MDO model for valves is established, which takes account of mechanical analysis, fluid mechanics analysis, thermal-mechanical coupled analysis and seismic analysis. On this basis, the MDO integrated system is constructed combined with some new techniques to solve the common and critical problems of optimal design of valves. The system takes interplay and coupling of each discipline into account, applies effective optimization strategy, information transmitting and concurrent design to get the synergistic effect produced by interaction of each discipline, and finally obtains the total optimum solution of valves, which, moreover, could provide technical reference for the practicality and commercialization of the integrated system in valves design optimization.