Present Design Model Research Articles

The Optimal Blading Design and CFD Analysis of Axial Flow Fan

This study proposes a method to optimize the blade angle and chord length distributions of axial flow fan rotor blade, and applied it to the design of the actual industrial axial flow fan. The present design model of the axial flow fan rotor blade is to construct and stack the section profiles using single circular arc and airfoil thickness distribution with the camber and stagger angles as design variables along the blade span height from hub to tip, and the chord length distribution is designed in a parabolic fashion from hub to tip. The performance and efficiency of the fan rotor blades are predicted by applying a through-flow analysis method to the 3D fan blade geometry obtained from the design variables of the camber angle, stagger angle, and chord length of the blade sections. These fan design and through-flow analysis methods are used as the simulation engine for optimization problem. Through applying the optimization algorithm, an optimal axial flow fan rotor is obtained with maximum efficiency and computational fluid dynamics analysis is performed to verify the result of the present optimal design. From the computational fluid dynamics calculation results, it can be seen that the present optimal design model has an efficiency improvement of about 2% compared to the initial design, and maintains relatively high efficiency even under partial load conditions.

The Design Models We Have Are Not the Design Models We Need

Whitbeck (1996) presents a design-anchored approach to ethics that provides a way to think about the intersection of instructional design and social justice. While ethics are typically treated as deciding between what is “right” or “wrong,” Whitbeck (1996) explains this is a simplistic view, as ethics are about confronting complex moral problems that require designers to devise responses (design). When critiqued through the lens of accessibility and equity and racial and economic inequalities, areas where present design models fall short become apparent. Ethics as design affords a way to see design models anew and reconsider design practices.

The Design Models We Have Are Not the Design Models We Need

Whitbeck (1996) presents a design-anchored approach to ethics that provides a way to think about the intersection of instructional design and social justice. While ethics are typically treated as deciding between what is “right” or “wrong,” Whitbeck (1996) explains this is a simplistic view, as ethics are about confronting complex moral problems that require designers to devise responses (design). When critiqued through the lens of accessibility and equity and racial and economic inequalities, areas where present design models fall short become apparent. Ethics as design affords a way to see design models anew and reconsider design practices.

УЧЁТ СДВИГА ПРИ РАСЧЁТЕ БАЛОК СУДОВЫХ БОРТОВЫХ ПЕРЕКРЫТИЙ, ВОСПРИНИМАЮЩИХ ИНТЕНСИВНЫЕ ЛОКАЛЬНО РАСПРЕДЕЛЁННЫЕ НАГРУЗКИ

In the process of operation, shipboard beams are subjected to the impact of various types of loads, the greatest danger being intense local distributed loads which are the main cause of damage to ship hulls. Therefore, designing ship hulls with minimum weight characteristics, as well as choosing the optimum sizes of connections when reinforcing the beams, require to use methods for calculating hull structures under the action of local loads beyond the elastic limit. The paper presents design models that allow taking into account shear effects in the beam walls, as well as the effect of the support forces on elastic-plastic base on their deformation. These problems can be avoided, if the sector of the frame on which shearing force has reached the limit value can be replaced by an ideal cable lying on the elastic-plastic base with variable stiffness characteristics. The results of the calculation of the shipboard beams have been compared using the described approach and the method of "instantaneous variation of bending parameters". It is shown that for large deflections the discrepancy is insignificant, which is explained by the dominant influence of the support forces on the side skin and longitudinal forces on the behavior of locally loaded frames. The proposed technique allows taking into account the impact of shear effects on deformation of locally loaded frames, which can be used in design and modernization of ship hulls to select the optimum sizes of connections.

Navigation of autonomous mobile robot using adaptive network based fuzzy inference system

Intelligent soft computing techniques such as fuzzy inference system (FIS), artificial neural network (ANN) and adaptive neuro-fuzzy inference system (ANFIS) are proven to be efficient and suitable when applied to a variety of engineering systems. The hallmark of this paper investigates the application of an adaptive neuro-fuzzy inference system (ANFIS) to path generation and obstacle avoidance for an autonomous mobile robot in a real world environment. ANFIS has also taken the advantages of both learning capability of artificial neural network and reasoning ability of fuzzy inference system. In this present design model different sensor based information such as front obstacle distance (FOD), right obstacle distance (ROD), left obstacle distance (LOD) and target angle (TA) are given input to the adaptive fuzzy controller and output from the controller is steering angle (SA) for mobile robot. Using ANFIS tool box, the obtained mean of squared error (MSE) for training data set in the current paper is 0.031. The real time experimental results also verified with simulation results, showing that ANFIS consistently perform better results to navigate the mobile robot safely in a terrain populated by variety obstacles.

Optimal design of interior permanent magnet synchronous motor considering the manufacturing tolerances using Taguchi robust design

The manufacturing tolerance of the permanent magnets (PMs) is inherent in the produce of the machine. These tolerances influence back electromotive force (EMF), which is an important response of the motor. In order to enhance the quality of the product, the authors need to reduce these tolerances, but it is very difficult and involves a number of costs. Therefore, this study presents a robust design of the EMF characteristic analysis considering the manufacturing tolerances of PM in the interior PM synchronous motor (IPMSM). Among the robust optimisation method, Taguchi robust design based on orthogonal array was applied. Finally, the validity of the analysis result is verified by comparing the optimum design model with present design model (mass production model) ones.

Loading capacity of simply supported composite slim beam with deep deck

The composite slim beam has become popular throughout Europe in recent years and has also been used on some projects in China. With its steel section encased in a concrete slab, the steel-concrete composite slim beam can provide the floor construction with minimum depth and high fire resistance. However, the design method of the T-shape steel-concrete composite beam is no longer applicable to the composite slim beam with deep deck for its special construction, of which the present design models are not available but mainly depend on experiences. The elevation of the flexural stiffness and bending capacity of composite slim beams with deep deck is rather complicated, because the influences of many factors should be taken into account, such as the variable section dimensions, development of cracks and non-linear characteristics of concrete, etc. In this paper, experimental investigations have been conducted into the flexural behavior of two specimens of simply supported composite slim beam with deep deck. The emphases were laid on the bonding force on the interface between steel beam and concrete, the stress distribution of beam section, the flexural stiffness and bending capacity of the composite beams. Based on the experimental results, the reduction factor of equivalent stress distribution in concrete flange is suggested, and the calculation method of flexural stiffness and bending capacity of simply supported slim beams are proposed.

A precision design and NC manufacturing model for concave-arc ball-end cutters

Having first defined the helical angle as the angle between the cutting edge and the axis of rotation of the cutter, this paper then presents design models for producing the cutting edge and groove of a ball-end cutter with concave-arc generator. The relative feed speeds of the grinding wheel in the radial and axial directions during NC machining of the cutter are derived based upon a given speed of rotation. The feed speed of the grinding wheel in the radial direction is modified according to the cross section of the groove that passes through the center of the cutter sphere. The paper presents a method for manufacturing a concave-arc ball-end (CABE) cutter using a 2-axis NC machine. The models that are used to calculate the actual obtained groove and the computer simulation method are also included. To further enhance the accuracy of the mathematical models, a compensatory machining process that eliminates residual profile on the revolving surface is presented. This paper provides a valuable reference for the design and machining of this cutter type.

Anisotropic Conducting Adhesives for Electronic Interconnection

This paper presents analytical and computational models of adhesive joints constructed from anisotropic conducting materials. Such materials are becoming increasingly important in the construction of fine pitch interconnection, for example the assembly of surface mounted components to printed circuit boards, and are likely to find considerable application in silicon die attach as alternatives to current ‘flip chip’ technologies. The paper presents design models of the mechanical and low frequency electrical behaviour of typical materials and relates these models to manufacturing process parameters.