Flow diagnostics

The measurement of flow properties within fluid handling systems is of utmost importance for efficient operation and control of such systems. For single phase flow systems, extensive research has been carried out world over to diagnose the flow properties both globally and locally. Considerable advancements are being made to perfect these technologies. For multiphase flows there is still a lot of scope for technological development that needs to take place to diagnose the flow conditions accurately efficiently and effectively. In this present paper two methods are described that can be used effectively for measurement of flow properties in solid-liquid flows and gas-liquid flows. One of the methods relies on isokinetic sampling used in conjunction with impact probe for the determination of solid distribution and solid velocity in solid-liquid flows through a pipeline. The other method relies on electrical resistance method to calculate local flow velocity corresponding to the dispersed phase as well as volume fraction and interfacial area concentration

Diagnostics Of Disks Around Hot Stars

We discuss three different observational diagnostics related to disks around hot stars: absorption line determinations of rotational velocities of Be stars; polarization diagnostics of circumstellar disks; and X-ray line diagnostics of one specific magnetized hot star, theta(1) Ori C. Some common themes that emerge from these studies include (a) the benefits of having a specific physical model as a framework for interpreting diagnostic data; (b) the importance of combining several different types of observational diagnostics of the same objects; and (c) that while there is often the need to reinterpret traditional diagnostics in light of new theoretical advances, there are many new and powerful diagnostics that are, or will soon be, available for the study of disks around hot stars

Fuel spray diagnostics

Several laser measurement methods are being studied to provide the capability to make droplet size and velocity measurements under a variety of spray conditions. The droplet sizing interferometer (DSI) promises to be a successful technique because of its capability for rapid data acquisition, compilation and analysis. Its main advantage is the ability to obtain size and velocity measurements in air-fuel mixing studies and hot flows. The existing DSI at NASA Lewis is a two-color, two-component system. Two independent orthogonal measurements of size and velocity components can be made simultaneously. It also uses an off-axis large-angle light scatter detection. The fundamental features of the system are optics, signal processing and data management system. The major component includes a transmitter unit, two receiver units, two signal processors, two data management systems, two Bragg cell systems, two printer/plotters, a laser, power supply and color monitor

Fuel Spray Diagnostics

Fundamental experimental data base for turbulent flow mixing models is provided and better prediction of the more complex turbulent chemical reacting flows. Analytical application to combustor design is provided and a better fundamental understanding of the combustion process