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In this paper, an efficient aeroelastic model for morphing structures with corrugated panels is proposed, combining different fidelities of aerodynamic models. A finite element method with an actuation model is used to analyze the structural deformation of morphing structures. A vortex lattice method and Cartesian-grid-based computational fluid dynamics are individually coupled with the structural model to build the medium- and high-fidelity aeroelastic models. Three different morphing cases are simulated with the two fidelities of aeroelastic models to understand the influence of the model fidelity on the simulation results. Based on the comparison study, a new efficient aeroelastic model is proposed where the medium-fidelity aeroelastic model speeds up the calculations in the aeroelastic loop and the high-fidelity aeroelastic model computes accurate aerodynamic characteristics and necessary actuation loads. Computational time of the proposed method is half of the high-fidelity model while maintaining the computational accuracy.

Two new methods were developed for identifying Cynaeus angustus (LeConte) (Coleoptera: Tenebrionidae) by DNA amplification using simplex and real-time PCR targeting the cytochrome c oxidase subunit I (COI) sequence reported previously. The specificities of the PCR primers and probe were also confirmed by the two PCR methods using the 22 main stored-product insect species, including DNA samples from nine tenebrionid beetle species. The results showed that the newly developed simplex and real-time PCR-based methods have sufficient specificity for analysis. The limits of detection for C. angustus total DNA by the simplex and multiplex PCR were 320 fg and 20 pg, respectively.

The identification of insect species is generally achieved by analyzing the specific morphological characteristics or, in more recent years, by polymerase chain reaction (PCR) assays of DNA sequences. PCR assays, which detect specific segments of DNA, have been established as a highly sensitive method for a wide range of applications, including the verification of hereditary diseases and for criminal investigations. For the identification of insects, the CO1 (cytochrome c oxidase subunit I) gene of mitochondrial (mt) DNA is often used. However, analyses of the entire mtDNA sequence might yield more reliable regions for use in the identification of insect species. Here we developed a method for real-time PCR identification of the khapra beetle, Trogoderma granarium Everts, by comparing the whole mtDNA sequences of three species of dermestid beetle: the khapra beetle, the varied carpet beetle, Anthrenus verbasci (L.), and the black carpet beetle, Attagenus unicolor japonicus Reitter. Several khapra beetle-specific mtDNA regions were identified and selected for use in the real-time PCR identification of these beetles based on Taq-Man® chemistry. Specificity tests conducted with the DNAs of several insects, including those of the three beetles described above, revealed that the primer/probe sets designed for the real-time PCR were highly specific to their targets.

Transonic turbulent flows around the NASA Common Research Model are simulated to investigate the capability of the Cartesian-grid-based flow solver UTCart in three-dimensional high-Reynolds-number ...

Near-wall modeling for large-eddy simulation (LES) based on the lattice Boltzmann method (LBM) is applied to the unsteady aerodynamic simulations around the tandem cylinders and the 30P30N three-element high-lift airfoil using hierarchical Cartesian grids. The near-wall modeling of the inner turbulent boundary layer is essential for LES to accurately calculate the high Reynolds number wall-bounded turbulent flow with a reasonable calculation cost. Therefore, near-wall modeling for LES has been studied within the framework of the Navier–Stokes equations. However, LBM-based modeling is still in its early developing stage because of the LBM’s calculation algorithm using distribution functions on a non-body fitted Cartesian grid, and further developments are needed regarding the applicability to flow simulations around arbitrary complicated shapes that appear in the actual engineering field. In this study, aerodynamic simulations around tandem cylinders are conducted using the proposed near-wall modeling that reproduces the profiles of the turbulent boundary layer in turbulent channel flow simulations on a non-body-fitted Cartesian grid. The same benchmark problem is also calculated using the non-slip wall boundary condition (interpolated bounce-back scheme) for comparison. Those calculation results are validated through the comparisons with the available experimental measurements, and the effectiveness of the proposed near-wall modeling to high Reynolds number wall-bounded turbulent flow simulations around objects with curvilinear surfaces is demonstrated. Followed by the tandem cylinders, the aerodynamic simulation around the 30P30N three-element high-lift airfoil is also conducted in order to demonstrate the applicability to more complicated shapes. The simulation result shows that the proposed method can stably calculate the relatively complicated configuration such as the high-lift airfoil, and the potential of the proposed method to unsteady aerodynamic simulations around arbitrary complicated shapes is demonstrated.

An improved immersed boundary method for turbulent flow simulation on Cartesian grids is proposed. To determine the appropriate boundary conditions, near-wall approximation of the mean-flow equatio...

This study focuses on the immersed boundary method (IBM) for high Reynolds number compressible flow. Using the hierarchical Cartesian grid makes it difficult to resolve the thin boundary layer of high Reynolds number flow around an object because the grid is refined equally in every direction. To alleviate the requirement for the grid size of the wall, the development of a wall boundary condition using a turbulent wall function is necessary. The IBM development is based on a hierarchical Cartesian grid generator and compressible flow solver called the University of Tokyo Cartesian-grid-based automatic flow solver (UTCart). The flow solver is validated through subsonic flow over a 2D bump. The skin friction distribution is reproduced accurately by the proposed IBM. A flow around NASA common research model is solved. A flux-based method is developed based on the balance of the numerical fluxes and used for the evaluation of the aerodynamic forces. The results exhibit favorable agreement with the existing experimental data and numerical results from the body-fitted grid.

A new higher-order scheme for hyperbolic systems of conservation law on Cartesian grids with cell-based refinement is proposed. The scheme is based on the finite volume methods, which admits a simple formulation around the hanging-nodes. Dimension-by-dimension reconstruction is applied to utilize the advantage of Cartesian grids. A quadrature modification flux (QMF) is introduced, which modifies the second-order error term of the flux integration over the cell-interface. The QMF can be evaluated using the state variables and the first derivatives stored in the face-left and right cells. There is no need to calculate the point-value or to use multi-points flux quadrature. In addition, a two-step reconstruction method is introduced to achieve a higher-order reconstructed value. The scheme achieves fourth-order accuracy where the grids are locally uniform, and retains second-order accuracy around the hanging-nodes. The accuracy and efficiency of the scheme is demonstrated in some example problems: inviscid vortex advection, Shu–Osher problem, double Mach reflection, and transonic flow around the NACA 0012 airfoil. The present scheme is demonstrated to function stably and consistently.