The present work investigates turbulent velocity and temperature fields subject to strong wall injection in a channel using a Direct Numerical Simulation technique. A simplified model problem of the internal flows inside the hybrid rocket motors where a regression process at the wall is idealized by the wall blowing has been considered to gain a better understanding of how the turbulent structu...

The shape of the interface between two superimposed layers in a two-dimensional channel confined between a planar and a corrugated or indented wall is investigated in the limit of Stokes flow. A perturbation analysis for walls with small-amplitude sinusoidal corrugations reveals that an insoluble surfactant amplifies the deformation of the interface and causes a negative drift in the phase shif...

We numerically study the effect of solid boundaries on the swimming behavior of a motile microorganism in viscoelastic media. Understanding the swimmer-wall hydrodynamic interactions is crucial to elucidate the adhesion of bacterial cells to nearby substrates which is precursor to the formation of the microbial biofilms. The microorganism is simulated using a squirmer model that captures the ma...

background and objective: mediastinal masses in children are a heterogenous group of asymptomatic potentially life-threatening congenital, infectious, or neoplastic lesions that present complex diagnostic and therapeutic dilemmas. materials and methods: the clinical and laboratory features of 65 patients who had open biopsies in ali-asghar hospital over 11 years were reviewed. results: seventy-...

osteosarcoma (osteogenic sarcoma: os) is the most common primary malignant bone tumor of long bones, whereas primary osteosarcoma of chest wall, especially in sternum, is extremely rare. we report a 57-year-old man with an immobile slow growing mass located in the middle of the sternum. the patient had no significant pain or tenderness and the past medical history was not remarkable. ct-scan sh...