Experimental and theoretical investigations are presented for the maximum spread factor (βm) of an impacting droplet onto solid surfaces with contact angle hysteresis. Experiments were conducted deionized water on six different wettabilities. The examined Weber number ( We) falls between 10-1 103. A new energetic model adopting a rim-lamella shape is proposed to better represent at spread. dynamic (θβm) introduced in account curvature surrounding rim induced by surface lamella-rim thickness...

Comprehensive investigations were conducted on numerical methods for simulating high–pressure water jet in air impacting a flat plate. The primary focus was the influence of impact pressure exerted Taking into account principal characteristics jets air, Eulerian multiphase model selected as foundational approach flows. Firstly, two turbulence treatment investigated, revealing that mixture method yields superior results compared to per–phase method. Subsequently, effects models examined. Two...

This study aimed to enhance the impact resistance of fiber metal laminates (FMLs) and achieve lightweight optimization by incorporating a new thermoplastic resin, titanium alloy ultra-high-molecular-weight polyethylene (UHMWPE) produce novel type FMLs (PEFMLs). The PEFMLs was analyzed through low-velocity tests conducted at different energy levels. Subsequently, residual compression-after-impact (CAI) strength evaluated compression on impacted specimens. experimental findings revealed that...

Droplet impact on a smooth solid surface at atmospheric pressure was experimentally studied and physically interpreted. A particular emphasis of the study is effects liquid viscosity transition between droplet deposition (or spreading without breakup) disintegration (including splash receding breakup). Specifically, critical Weber number separating from decreases then increases with increasing Ohnesorge (Oh). The in low-Oh region breakup high-Oh were analyzed qualitatively based unbalanced...

Experimental and numerical investigations are presented for a theory-guided machine learning (ML) model that combines the Hashin failure theory (HFT) classical lamination (CLT) to optimize accelerate design of composite laminates. A finite element simulation with incorporation HFT CLT were used generate training dataset. Instead directly mapping relationship between ply angles laminate its strength stiffness, multi-layer interconnected neural network (NN) system was built following logical...

Mobile fans, as flexible and convenient new longitudinal ventilation smoke extraction equipment for tunnels, demonstrate more significant effectiveness in an emergency response to tunnel fires compared traditional methods. This study employs computational fluid dynamics simulation methods, selecting two fire scenarios investigate the effects of fan inclined angles airflow volumes on temperature distribution back-layering length tunnels. The results indicate that when using mobile fans at a...

As computational fluid dynamics (CFD) advances, entropy generation minimization based on CFD becomes attractive for optimizing complex heat-transfer systems. This optimization depends the accuracy of results, such that accurate turbulence models, as elliptic relaxation or blending become important. The performance a previously developed model (the SST k-ω-φ-α model) to predict rate in fully turbulent circular tube flow with constant heat flux was studied provide some guidelines using...

On the basis of a previously developed elliptic blending turbulence model (SST–k–ω–φ–α model), scale-adaptive simulation (SAS) is by following Menter and Egorov’s SAS concept. An source term, which related to ratio modeled scale von Kármán length scale, introduced into corresponding length-scale determining equation. The major motivation this study that conventional unsteady Reynolds-averaged Navier–Stokes (URANS) models provide only large-scale unsteadiness. introduction term allows...

A new turbulence model based on elliptic blending, termed as k − ω ϕ α model, is developed. This uses the latest version of Wilcox's in near-wall region and changes gradually to elsewhere. The capabilities present are evaluated separation flows, i.e. 2D fully developed channel flow, asymmetric plane diffuser flow backward-facing step comparison with available direct numerical simulation (DNS) experimental data. computational results compared also those from popular original more stable than...

Collision accidents of container ships occur occasionally, in the past decades. Due to fast speed and large opening deck ships, it is easy generate serious consequences case collision. This paper studies dynamic response, structure failure energy absorption The material criterion affects response prediction hull under collision scenario. structures are subjected complex stress state load, so forms different. In this study, two criteria investigated ship simulation. One them a constant that...

Numerous studies have demonstrated that under low-velocity, low-energy impact conditions, although the surface damage to fiber-reinforced composite laminates may be minimal, significant internal can occur. Consequently, a progressive finite element model was specifically developed for thermoplastic carbon subjected low-speed loads, with objective of analyzing behavior impacts varying energy levels. The utilizes three-dimensional Hashin criterion predicting intralayer initiation, cohesive...

Using two different methods, a previously developed elliptic blending model (the original STT k-ω-φ-α model) is modified for sensitization to streamline curvature. One method involves modifying the dissipation term in turbulent equation, while other constructs new formulation kinetic energy production based on an explicit algebraic stress model. The capabilities of proposed models are evaluated by applying them three flows with curved surfaces; namely, two-dimensional (2D) infinite...

Pressure transducers and high-speed photography technology were applied on the experimental device which formed axisymmetrical dissemination of glycerine. The instability development at gas/liquid interface primary breakup recorded by high speed photographs. It can be concluded that wavelength initial disturbance waves will decrease with incensement shock wave intensity. At same time, degree mixing spike airflow also increased. acceleration liquid front remains unchanged in earlier stage...

The Multi-Stage (MUSTA) scheme was used to construct the numerical fluxes when hyperbolically degenerate governing equations, in which independent eigenvectors can not be found, are numerically solved for dilute particle-gas two-phase flows. abilities of MUSTA various problems were analyzed. It found that is effective even very complicated problem although appropriate total number stages should carefully selected. When equals 3 or 4, as accurate Riemann solver most cases.

The detonation of fine aluminum-oxygen mixtures was numerical simulated using a hybrid combustion model. emphasis laid on the influence decomposition Al 2 O 3 structure. Results showed that including will limit gas temperature behind wave below certain value. On other hand, double-wave structure appear in pressure profiles cases with rich-dust condition if is not included.

The Influence of six kinds combinations different boundary conditions on the maintenance homogeneity atmospheric layer in computational wind engineering was investigated. inlet condition applied by either prescribing velocity and turbulent quantities or using a periodic boundary. top includes symmetry, quantities, constant static pressure applying driving shear stress. Numerical results show that stream-wise dissipation rate are almost immune to conditions, but kinetic energy is affected...