Diffuser (thermodynamics)

About: Diffuser (thermodynamics) is a research topic. Over the lifetime, 6731 publications have been published within this topic receiving 54738 citations.

Microwave fluid heating system

Abstract: A microwave heating system utilizing a magnetron for generating the microwaves. The microwaves are sent to a diffuser which spreads the microwaves in an upper chamber of a housing from where they can bounce off the metal walls of the upper chamber and pass through a clear plastic material into a lower chamber. A fluid passes through a circuitous path in the lower chamber and is heated by means of the microwaves.

PIV validation of different turbulence models used for numerical simulation of a centrifugal pump diffuser

Abstract: Purpose The purpose of this study is to validate the different turbulence models using in the numerical simulation of centrifugal pump diffuser. Computational fluid dynamics (CFD) has become the main method to study the pump inner flow patterns. It is important to understand the differences and features of the different turbulence models used in turbomachinery. Design/methodology/approach The velocity flow fields in a compact return diffuser under different flow conditions are studied and compared between CFD and particle image velocimetry (PIV) measurements. Three turbulence models are used to solve the steady flow field using high-quality fine structured grids, including shear stress transport (SST) k-w model, detached-eddy simulation (DES) model and SST k-w model with low-Re corrections. Findings SST k-w model with low-Re correction gives better results compared to DES and SST k-w model, and gives a good predication about the vortex core position under strong part-loading conditions. Originality/value A special test rig is designed to carry out the 2D PIV measurements under high rotating speed of 2850 r/min, and the PIV results are used to validate the CFD results.

Jet driven surgical suction device and method of using

Abstract: A probe for use in collecting liquids entrained with a gaseous component, particularly collecting a patient's blood with entrained gas bubbles from a surgical site for autologous reinfusion. The probe separates the gaseous component from the collected liquid, particularly separating air bubbles from blood cells to inhibit hemolysis, platelet degradation and protein denaturation. An elongated probe body has a distal end to be inserted into the liquid to be collected through an inlet by jet pump action into a centrally disposed mixing chamber. A diffuser is formed within the probe body proximal to and in axial alignment with the inlet and mixing chamber leading to a liquid exit. A jet pump nozzle is formed in the probe distal tip surrounding the inlet in the form of an annular chamber into which pressurized drive fluid is introduced through a distribution channel system extending along the probe body from the proximal end. The drive fluid is ejected in a swirling vortex from the jet pump nozzle around the periphery of the mixing chamber effecting a sub-atmospheric pressure for suctioning the liquid to be collected and the gaseous component thereof into the inlet and mixing chamber. The drive fluid mixes therewith in the swirling vortex and propels the mixture into the diffuser while concentrating the gaseous component in the center of the swirling vortex as a stream. A gas evacuation tube is oriented in the centrally disposed concentrated gaseous stream for evacuating the gaseous component from the mixture before it is propelled into the diffuser. In the autologous reinfusion context, the entrained air bubbles are concentrated and removed in the probe from the blood as they are suctioned into the swirling vortex to reduce hemolysis. When mixed in the vortex, the blood and drive fluid mixture is pressurized to inhibit further air bubble formation.