Bravery

Abstract

“BRAVERY” is an engineering calculation method that offers theoretical solutions rather than numerical solutions, and can be used to simulate the problems encountered in the engineering field, and subsequently to be used in engineering design.

Description

BRIEF SUMMARY

“BRAVERY” is an engineering calculation method that offers theoretical solutions rather than numerical solutions, and can be used to simulate the problems encountered in the engineering field, and subsequently to be used in engineering design.

BACKGROUND

After the Finite Element Method was created, the engineering field entered a more mature and steady stage in terms of engineering calculation. However, the analysis results of the Finite Element Method were often unsatisfactory to engineering designers, and its accuracy has yet to be improved. “BRAVERY” is an engineering calculation method that offers theoretical solutions rather than numerical solutions, and can be used to simulate the problems encountered in the engineering field, and subsequently to be used in engineering design. The advantage of BRAVERY is that it can solve any engineering problem if engineers can precisely define their deformation curve or deformation surface.

The Finite Element Method requires that engineers must have a basic concept of the engineering problems in order to perform finite element analysis. BRAVERY also has the same requirement, or even a higher requirement regarding this concept, because engineers can only adopt the BRAVERY calculation method after they have reached an understanding of the engineering problems they are going to analyze, to a considerable degree (i.e., having already seen photos, images or data of similar problems, and can almost define the deformation curve or deformation surface).

With the Finite Element Method, if engineers have no basic concept of the engineering problems, the error in the engineering analysis results may go unseen, thus leading to the difficulty in determining whether the problem lies in errors with the engineering model, improper setting of boundary conditions, element selection error, poor mesh generation, or even a problem with the finite element software itself. Although BRAVERY has a higher requirement for engineers, its aim is the same as that of the Finite Element Method, namely, to avoid errors in the results of the engineering analysis. Simply stated, the Finite Element Method involves calculating results in a backwards direction, while BRAVERY involves predicting results in a forward direction.

DETAILED DESCRIPTION

BRAVERY is an engineering calculation method which creates an energy equivalent formula based on the given deformation curve or deformation surface to deduce the initial hypothetical variables.

Claims

1. BRAVERY is an engineering calculation method which first calculates the axial strain and shear strain in various directions with the given deformation curve or deformation surface equation, and then establishes an equation based on the kinetic energy (K=½ mν2) or the work (W=Fd) of the load with the object's strain energy (U=½∫V Eε2dV) to obtain a theoretical energy equivalent formula. Then, numerical methods are used to solve the equation in order to obtain the desired dimension variables via repeated calculations in a process based on trial and error. Finally, based on the material stress as the basis of equation control, the value of the dimension variables is obtained. The following is an example of a calculation of a high-speed ball hitting a circular plate, with simplified theoretical derivation. Here, the impact kinetic energy can be expressed as: K=½mξ2

2. When BRAVERY is applied to materials which have already been deformed plastically (for example, pressing processing), it is necessary to evaluate its amount of plastic deformation and the residual stress in order to reduce the allowable stress value used in calculation. Otherwise, pressing may cause the material to undergo inner plastic deformation, leading to an over-estimation of the design strength, and resulting in design failure.

3. BRAVERY may be developed into engineering software for calculation purposes, to shorten the calculation time spent by engineers. The engineering software should provide, and allow manual creation of, commonly used deformation curve and deformation surface modules for engineers to quickly establish theoretical energy equivalent formulae for the engineering problems encountered, and then solve by repeated trial and error process using the built-in numerical methods to derive the value of the initial hypothetical variables. When the results are obtained, the strain and stress values of each block are calculated in accordance with the strain equation, to generate a graph for engineers to examine and verify. The definitions of the deformation curve and deformation surface are derived from the curve or curved surface, and through the equation definition for producing lines through tool functions, the deformation curve and deformation surface equation can be precisely defined.