A comprehensive numerical study of the combustion dynamics in a lean-premixed swirl-stabilized combustor is described. The analysis treats conservation equations three dimensions and takes into account e niterate chemical reactions variable thermophysical properties. Turbulence closure achieved using largeeddy-simulation technique. compressible-e ow version Smagorinsky model employed to describe subgrid-scale turbulent motions their effect on large-scale structures. level-set amelet library...

Turbulent swirling flows injected into a coaxial dump chamber at different swirl numbers were studied using large-eddy simulations. The Favre-filtered conservation equations of mass, momentum, and energy in three dimensions solved numerically by means finite-volume approach. Results have been validated against experimental data terms mean flow velocity turbulence properties. work provides insight several salient features flows, including vortex breakdown, shear-layer instability,...

The purpose of this research is to investigate the operation condition fluidic thrust vector using injection control flow tangential main jet direction; co-flow injection. physical model concern includes a chamber and supersonic nozzle for injection, two chambers with slots Steadystate numerical experimental studies were conducted operating parameters; detailed structures, deflection angles, shock effects observed near exit. An unsteady calculation was analyze dynamic characteristics...

The purpose of this experimental research is to investigate combustion characteristics the cylindrical multiport grain a hybrid rocket motor and highlight port number effects on regression rate. physical model concern includes an oxidizer supply system, fuel grain, combustor with pre- postchamber. Several design parameters, such as number, type (polyethylene polymethylmethacrylate), end-burning effects, are experimentally analyzed using small- large-scale where diameters 50 96 mm used,...

Unsteady numerical simulations of pintle nozzles were implemented to investigate dynamic characteristics various configurations. To take into account the effects shape and movement, a sliding mesh method was applied. The physical nozzle throat based on location analytically investigated found compare well with results. static results are verified experimental flow separation shock trains as strokes analyzed according three models. response lag sensitivity chamber pressure performance...

A comprehensive numerical study is conducted to explore the dynamic behaviors of a flame stabilized by triangular bluff body in straight chamber. The formulation accommodates complete set conservation equations with turbulence closure achieved large eddy simulation (LES) technique. G-equation-based level-set flamelet approach employed model interactions between premixed combustion and turbulence. Both non-reacting reacting flows are treated, special attention given effect inlet boundary...

TiO2-coated boron particles were prepared by a wet ball milling method, with the particle size distribution and average being easily controlled varying operation time. Based on results from X-ray photoelectron spectroscopy, transmission electron microscopy, energy dispersive analysis, Fourier transform infrared it was confirmed that initial oxide layer surface removed process, new B–O–Ti bond formed surface. The uniform TiO2 150 nm estimated to be 10 thick. linear sweep voltammetry, cyclic...

A Novel blended solid fuel which mixes paraffin wax of alkane and LDPE alkene is invented tested in a slab motor hybrid rocket to visualize droplet entrainment analyze combustion characteristics. The mechanical strength was investigated increasing the wt%. Overall regression rate PR95PE05 found be 3.9 factors higher compared that HDPE. Improved efficiency achieved with respect pure where performance gain comparable SP-1a Stanford University. Analysis spectrum chamber pressure revealed no...

The design and operational parameters of rocket exhaust diffusers equipped to simulate high-altitude performance on the ground were investigated characterized using a comprehensive approach (theoretical, numerical, experimental). physical model concern includes motor, vacuum chamber, diffuser, which have axisymmetric configurations. Further, characteristics diffuserwereanalyzed froma flowdevelopmentpointof view.Emphasiswasplacedondetailed flowstructure inthe observe pressure oscillation in...

Abstract The combustion of zirconium potassium perchlorate (ZPP) in a closed vessel is modelled and validated through numerical simulation. Because the extremely high pressure oscillation occurs less than millisecond, an in‐house computational fluid dynamics (CFD) code used to observe detailed flow structures determine adequate burning characteristics, including rate. A hybrid RANS/LES scheme with 5 th order upwind weighted essentially non‐oscillatory (WENO) implemented capture complex,...

A detailed three-dimensional numerical simulation was conducted to investigate the flow and -air mixing characteristics in a scramjet engine with two intake sidewalls cavity flameholder. Turbulence closure achieved using model that combines low-Reynolds-number two-equation Sarkar Wilcox's compressible turbulent-correction model. The governing equations were solved numerically by means of finite volume, preconditioned flux-differencing scheme. Cases without considered. Intake found strongly...