The study of flapping-wing aerodynamics faces a large control space with different wing kinematics and deformation. adjoint-based approach, by solving an inverse problem to obtain simultaneously the sensitivity respect all parameters, has computational cost independent number parameters becomes efficient tool for problems space. However, adjoint equation is typically formulated in fixed fluid domain. In continuous formulation, moving boundary or morphing domain results inconsistency...

It is important to understand the impact of wing-morphing on aerodynamic performance in study flapping-wing flight birds and insects. We use a flapping plate hinged with trailing-edge flap as simplified model for flexible/morphing wings hovering. The motion optimized by an adjoint-based approach. configuration suggests that can substantially enhance overall lift. Further analysis indicates lift enhancement from change circulation two ways: local rotational flap, modification vortex shedding...

Adjoint-based methods show great potential in flow control and optimization of complex problems with highor infinite-dimensional space. It is attractive to solve an adjoint problem understand the effects from multiple parameters a few performance indicators flight birds or insects. However, traditional approach formulate becomes either impossible too when arbitrary moving boundary (e.g. flapping wings) its perturbation considered. Here, we use non-cylindrical calculus define perturbation. So...

An adjoint-based optimization is applied to study the thrust performance of a pitching–rolling ellipsoidal plate in uniform stream at Reynolds number 100. To achieve highest thrust, optimal kinematics motion sought control space including pitching amplitude, rolling and phase delay between motions. A continuous adjoint approach with boundary being handled by noncylindrical calculus developed as computationally efficient algorithm deal large morphing domain. The comparison other reference...

In our previous work, a strong-coupling approach was successfully used to simulate highly flexible wings interacting with surrounding fluid flows in globally Eulerian framework for both and solid. However there strong assumption simplify the formulation: wing structure has same density as fluid. Here, using fast-tracking method efficiently identify solid areas solving modified momentum equations pressure Poisson equation variable (but still incompressible) density, we were able apply idea...

In the present work, a duct geometry is optimized to reduce flow distortion using adjoint method. The S-duct from AIAA Propulsion and Aerodynamics Workshop (PAW [1]). ANSYS Fluent Adjoint solver used run design optimization study. workflow involves 4-step process: CFD run, calculation, calculation based on sensitivity data environment constraints, mesh update. This process repeated until optimum obtained. variance of total pressure at Aerodynamic Interface Plane (AIP) chosen as quantity...

With the deep integration of energy revolution and digital revolution, various new businesses, formats business models are constantly emerging in electric power industry, technologies developing rapidly. The enterprise architecture urgent need grid can be rapidly transformed to keep pace with development Times. But at present, company because lack effective management means, there is unclear, standard not unified assets master problems such as nonstandard, architecture, control, produce...

The study of flapping-wing aerodynamics is a problem with very large control space. Adjoint-based approach, by solving an inverse problem, can be used here as efficient tool for optimization and physical understanding. However, the adjoint equation typically formulated in fixed domain. moving boundary or morphing domain brings inconsistency definition arbitrary perturbation at boundary, which then proposes new challenge if parameters happen to also boundary. An unsteady mapping function,...

In the present work, a sharp interface immersed boundary method using ghost-cells is implemented in traditional 5th-order WENO scheme for shock capturing. To avoid non-physical negative density and pressure involved high order conservative schemes, cut-off flux limiter introduced to enforce positivity-preserving property, which allows simulate flow near vacuum with strong discontinuities. The combined approach was first benchmarked by steady oblique reflection problem an exact solution from...

Spray nozzle is a key component in equipment for plant protection and water-saving irrigation. The fan kind of spray nozzle, which widely used agriculture forestry irrigation control diseases, insects, weeds. In consideration the increasing velocity flow field, when hydraulic pressure remains unchanged path becomes narrow, because increase drops can penetrability into canopy, new with multi entries simple inner structure was designed influences its parameters on field were analyzed using...

Transonic unsteady aerodynamics model can be obtained by CFD/CSD coupling computation, but it is disadvantaged to analyze and integrate ASE problems because of the high order model. The dealt with reduction technique using system differentiate analyses balanced truncation in this paper, low Outlines paper generalized as follow: 1) reduced-order (ROM) gained applying Volterra series theory, aeroservoelasticity (ASE) configuration dynamics servo dynamics; 2) a lower method; 3) based on mixed...

The main goal of this paper is to analyze the flutter boundary, transient loads a supersonic fin, and with perturbation.Reduced order mode (ROM) based on Volterra Series presented calculate CFD/CSD coupling used compute aerodynamic load.The Volterra-based ROM obtained using derivative unsteady stepresponse, infinite plate spline perform interpolation physical quantities between fluid structural grids.The results show that inertia force plays significant role in loads, moment cause by lager...

Abstract For swirl-stabilized gas turbine combustors, turbulence modelling is generally undertaken using Scale-Resolved Simulations (SRS) methods such as Large Eddy (LES). However, LES expensive due to large mesh sizes and small time-step size required estimate the correct large-scale motion generated within combustor domain. While Reynolds Averaged Navier Stokes (RANS) models are computationally very efficient in predicting qualitative behaviour, lack fidelity predict complex flow...

Abstract Turbulence modeling plays a crucial role in swirl-stabilized gas turbine combustors, typically relying on scale-resolved simulations (SRS) such as large eddy (LES). However, LES is computationally expensive due to the need for fine mesh resolution and small time-steps required capture combustor's large-scale turbulence motion accurately. On other hand, Reynolds-averaged Navier–Stokes (RANS) models while efficient, lack fidelity predicting complex flow characteristics swirl In this...