Heat-transfer and surface-pressure measurements for the SSME fuel-side turbopump turbine

Detailed heat flux and surface pressure distribution on the first-stage vane and blade of the Space Shuttle Main Engine fuel side turbopump turbine are examined. The specific turbine being utilized for the study is a combination of actual engine hardware and reproduced hardware consistent with that being used at NASA-Marshall for the initial measurements in their newly constructed blow-down turbine test facility. The facility is of the short duration shock tunnel variety, which permits use of thin film thermometers which are used to measure the surface temperature histories at prescribed locations on the turbine component parts. Heat flux values are then inferred from the temperature histories using standard data reduction procedures. The measurement program is described in detail

Study of mechanism which causes film formation on mercury surfaces

The mechanism by which small quantities of dissolved tin, sodium, and lithium lower the rate of evaporation of mercury in vacuum is determined. An apparatus was built in which dilute amalgams could be prepared and studied in an oxygen-free environment before being exposed to oxygen under controlled conditions. The apparatus was able to maintain a pressure of less than 1.3 x 0.000001 N/sqm (10 to the minus 8th power torr) of gases and vapors other than mercury and less than 1.3 x 10 to the minus 8th N/sq m (10 to the minus 10th power torr) partial pressure of oxygen; also, it provided for mechanical sweeping of the liquid metal surfaces in the vacuum environment. The rates of evaporation of pure mercury and of dilute amalgams of tin (52 ppm), sodium (229 ppm), and lithium (165 ppm) were determined at temperature between 25 and 55 C both before and after 70 minute exposures to an approximately 270 N/sq m (2 torr) pressure of oxygen. The rates of evaporation of the pure mercury and the amalgams as first prepared were similar but the rates for the amalgams were reduced by at least 80% at 25 C as a result of the exposure to oxygen. The effect of the oxygen treatment could be completely removed by sweeping the amalgam surfaces. It was concluded that the reduced rates of evaporation resulted from the formation of transparent, insoluble, oxide films on the amalgam surfaces

Water separator

An apparatus for separating liquids from gases or gaseous fluids is described. Features of the apparatus include: (1) the collection and removal of the moisture in the fluid is not dependent upon, or affected by gravity; (2) all the collected water is cyclically drained from the apparatus irrespective of the attitude of the separator; and (3) a fluid actuator is utilized to remove the collected water from the separator

The Resistivity of Microorganisms to Thermal Inactivation by Dry Heat Final Report

Microorganism resistivity to thermal inactivation by dry heat - glass fibers and membrane filter

Diffusion of Competing Innovations: The Effects of Network Structure on the Provision of Healthcare

Medical innovations, in the form of new medication or other clinical practices, evolve and spread through health care systems, impacting on the quality and standards of health care provision, which is demonstrably heterogeneous by geography. Our aim is to investigate the potential for the diffusion of innovation to influence health inequality and overall levels of recommended care. We extend existing diffusion of innovation models to produce agent-based simulations that mimic population-wide adoption of new practices by doctors within a network of influence. Using a computational model of network construction in lieu of empirical data about a network, we simulate the diffusion of competing innovations as they enter and proliferate through a state system comprising 24 geo-political regions, 216 facilities and over 77,000 individuals. Results show that stronger clustering within hospitals or geo-political regions is associated with slower adoption amongst smaller and rural facilities. Results of repeated simulation show how the nature of uptake and competition can contribute to low average levels of recommended care within a system that relies on diffusive adoption. We conclude that an increased disparity in adoption rates is associated with high levels of clustering in the network, and the social phenomena of competitive diffusion of innovation potentially contributes to low levels of recommended care.Innovation Diffusion, Scale-Free Networks, Health Policy, Agent-Based Modelling

Heat transfer and pressure measurements and comparison with prediction for the SSME two-stage turbine

Time averaged Stanton number and surface pressure distributions are reported for the first stage vane row, the first stage blade row, and the second stage vane row of the Rocketdyne Space Shuttle Main Engine (SSME) two-stage fuel-side turbine. Unsteady pressure envelope measurements for the first blade are also reported. These measurements were made at 10 percent, 50 percent, and 90 percent span on both the pressure and suction surfaces of the first stage components. Additional Stanton number measurements were made on the first stage blade platform, blade tip, and shroud, and at 50 percent span on the second vane. A shock tube was used as a short duration source of heated and pressurized air to which the turbine was subjected. Platinum thin film heat flux gages were used to obtain the heat flux measurements, while miniature silicon diaphragm flush-mounted pressure transducers were used to obtain the pressure measurements. The first stage vane Stanton number distributions are compared with predictions obtained using a version of STAN5 and quasi-3D Navier-Stokes solution. This same quasi-3D N-S code was also used to obtain predictions for the first blade and the second vane

Measurement of NO plus plus e minus dissociative recombination in expanding air flows

Measurement of nitric oxide ion-electron dissociative recombination in expanding air flow