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The openings on aircraft structures can be modeled from an aerodynamical point of view as lid-driven cavities (LDC). This paper aims to show the primary verification and validation (V&V) process in computational fluid dynamics (CFD, and to investigate the influences of numerical settings on the efficiency and accuracy for solving the LDC problem.

To dig into the details of CFD approaches, this paper outlines the design, implementation, V&V and results of an efficient explicit algorithm. The parametric study is performed thoroughly focusing on various iteration methods, grid density discretization terms and Reynolds number effects.

This study parameterized the numerical implementation which provides empirical insights into how computational accuracy and efficiency are affected by changing numerical settings. At a low Reynolds number (not over 1,000), the time-derivative preconditioning is necessary, and k = 0.1 can be the optimal value to guarantee the efficiency, as well as the stability. A larger artificial viscosity (c = 1/16) would relieve the calculating oscillation issue but proportionally increase the discretization error. Furthermore, the iteration method and the mesh quality are two key factors that affect the convergence efficiency, thus need to be selected “wisely”.

The study shows how numerical implementation can enhance an accurate and efficient solution. This workflow can be used to determine the best parameter settings whenever CFD researchers applying this LDC problem as a complementary design tool for testing newly developed solvers.

The studied LDC problem is representative of CFD analysis in real aircraft structures. These numerical simulations provide a cost-effective and convenient tool to understand the parameter sensitivity, solution receptivity and physics of the CFD process.

The purpose of this study is to present the optimization of the design and measurement principle of a six-component force/thrust measurement stand. This study highlights some key problems found in previous studies and proposes improvements in design and measurement principles.

The numerical simulation approach is used to verify the proposed improvements. An improved design and measurement principle are proposed and to verify the proposed improvements, simulation experiments are conducted. The data obtained from simulations are analyzed through the proposed improved measurement principle. The proposed stand is capable of measuring the main thrust and other components as pitch, yaw and roll. The stand is capable of measuring the main thrust more than 50,000 N and orthogonal thrust components more than 1,000 N. Improved design of measurement stand is also capable of measuring moments in three-axis more than 150 Nm. Thrust stand consists of two main sections: front and rare. Stand consists of seven piezoelectric force sensors to measure all components of force.

The simulations experiments and basic theoretical laws of kinematics prove that the proposed design indeed improves the precision of measurement and also enhance the efficiency of design. Evaluation results show that the measurement stand designed is highly functional. Non-linearity, coupling and repeatability errors are found to be within acceptable range during numerical simulations.

This study is unique in this kind. This study identifies the key problems found in previous studies and proposes an improved design and measurement principle. This study provides evidence for the improvements to be really functional and necessary.