Cavitation and turbulence in a diesel injector nozzle has a great effect on the development and primary breakup of spray. However, the mechanism of the cavitation flow inside the nozzle and its influence on spray characteristics have not been clearly known yet because of the internal nozzle flow complexities. In this paper, a comprehensive numerical simulation is carried out to study the intern...

DLR Lampoldshausen carried out cold flow tests to study the flow field in a truncated ideal contour nozzle at low nozzle pressure ratios. A convex shaped Mach disk was found for nozzle pressure ratios less than 10 and a slight concave one for nozzle pressure ratios more than 20. Due to boundary layer transition the convex Mach disk is temporary tilted and redirects the flow towards the nozzle w...

Vortex breakdown of swirling, round jet flows is investigated in the compressible, subsonic regime by means of Direct Numerical Simulation (DNS). This is achieved by solving the compressible Navier–Stokes equations on a cylindrical grid using high-order spatial and temporal discretization schemes. The Reynolds number is Re = ρ c w ◦ c R ◦/μ◦c = 5000 and the flow is moderately compressible with ...

The cold gas micro-propulsion system can provide low noise and ultra-high accuracy thrust for satellite platforms space gravitational wave detection, high-precision earth gravity field measurement. In this study, the effect of different needle valve opening ratios on rarefied flow characteristics a micro-nozzle in was investigated based DSMC method. special feature currently studied is that it ...

A Southwest Electrostatic Sprayers, Inc., nozzle was configured to a Hudson PortaPak backpack. A test was run to compare deposition of BVA no. 13 oil by the electrostatic nozzle to a standard nonelectrostatic nozzle as collected by Teflon slides. Results indicate that 100% greater deposition occurred with the electrostatic nozzle.

This article developed a 6120-type diesel particulate filter pulse clean and regeneration control system with a high efficiency, simple reliable use. And it has determined the spray nozzle diameter, the injection distance, the injection pressure, the pulse width, the injection time of five factor optimal fit experiment parameter. This control system can flow the type honeycomb ceramics filter t...

We have measured the brightness of several helium free jet sources. Five converging nozzles with diameters between 0.6 and 5 m, and three tube nozzles with diameters between 2 and 10 m were studied at stagnation temperatures of 77 and 300 K and at stagnation pressures depending on nozzle size from 350 to 17000 kPa. Smaller nozzles produced higher brightness beams with values approaching 1028 s ...

Poly-ether-ether-ketone (PEEK) fabricated by fused deposition modeling for medical applications was evaluated in terms of mechanical strength and in vitro cytotoxicity in this study. Orthogonal experiments were firstly designed to investigate the significant factors on tensile strength. Nozzle temperature, platform temperature, and the filament diameter were tightly controlled for improved mech...