Radial inflow turbine design charts

Design charts were prepared for the selection of turbine geometry corresponding to maximum turbine efficiency. Optimum values can be determined as functions of specific speed

Current and future technology in radial and axial gas turbines

Design approaches and flow analysis techniques currently employed by aircraft engine manufacturers are assessed. Studies were performed to define the characteristics of aircraft and engines for civil missions of the 1990's and beyond. These studies, coupled with experience in recent years, identified the critical technologies needed to meet long range goals in fuel economy and other operating costs. Study results, recent and current research and development programs, and an estimate of future design and analytic capabilities are discussed

Analytical Investigation of the Significance of Turbine-Inlet Temperature in High-Energy Rocket Turbodrive Applications

The effect of turbine-inlet temperature on rocket gross weight was investigated for three high-energy long-range rockets in order to explore the desirability of turbine cooling in rocket turbodrive applications. Temperatures above and below the maximum that is permissible in uncooled turbines were included. Turbine bleed rate and stage number were considered as independent variables. The gross weight of the hydrogen-reactor system was more sensitive to changes in turbine-inlet temperature than either the hydrogen-oxygen or the hydrogen-fluorine systems. Gross weight of the hydrogen-reactor system could be reduced by 2.6 percent by the use of cooling and a turbine-inlet temperature of 3000 R. The reductions in the first stages of the hydrogen-oxygen and hydrogen-fluorine systems were 0.7 and 0.2 percent, respectively. The effect of turbine-inlet temperature on rocket gross weight was small because the resulting turbine weight and bleed rate variations were small. Since these small gains must be balanced against considerations of greater cost, weight, and complexity as well as lessened reliability with a system utilizing a cooled turbine, none of the systems investigated showed gains warranting the use of turbine cooling

Analysis of Broadcast Authentication Mechanism in Selected Network Topologies

This paper deals with simulation of the broadcast authentication protocols using Colored Petri Nets and further optimizations in Matlab environment. Typical application of broadcast authentication protocols can be configurations where only one transmitter with multiple recipients exists (such as message exchange in sensor networks routing protocols, or the leader election process in sensors network). Authentication of every packet seems to be very effective way to mitigate an attack, however resulting in increase of end-to-end delay. To mitigate this drawback, the broadcast authentication protocols have been proposed. Concept of optimization of the broadcast authentication protocol DREAM parameters in a special case of fully N-ary tree and general random topology containing the same amount of nodes with regard to delay and energy consumption minimization is showed in the paper. Protocol DREAM was taken as an example of broadcast authenticating protocol to show how Color Petri Nets can be used to create a fully functional model of the protocol