Surface pressure measurements on the blade of an operating Mod-2 wind turbine with and without vortex generators

Pressure measurements covering a range of wind velocities were made at one span location on the surface of an operating Mod-2, 2500 kW, wind turbine blade. The data, which were taken with and without vortex generators installed on the leading edge, show the existence of higher pressure coefficients than would be expected from two-dimensional wind tunnel data. These high pressure ratios may be the result of three-dimensional flow over the blade, which delays flow separation. Data are presented showing the repetitiveness of abrupt changes in the pressure distribution that occur as the blade rotates. Calculated values of suction and flap coefficients are also presented

Condensation-nuclei (Aitken Particle) measurement system used in NASA global atmospheric sampling program

The condensation-nuclei (Aitken particle) measuring system used in the NASA Global Atmospheric Sampling Program is described. Included in the paper is a description of the condensation-nuclei monitor sensor, the pressurization system, and the Pollack-counter calibration system used to support the CN measurement. The monitor has a measurement range to 1000 CN/cm cubed and a noise level equivalent to 5 CN/cm cubed at flight altitudes between 6 and 13 km

Dynamics of short pressure probes

Report presents practical information for incorporating particle impact protection features and average total pressure measurement into probe design while optimizing probe transient response. Computer program calculates probe response, based on Bergh-Tijdeman equation

How do Multinationals Build Social Capital? Evidence from South Africa.

This paper looks at the self-reporting of social engagement by multinational firms in South Africa, developing previous measures of social capital to fit the unique context of the multinational firm in particular mapping the configurations of declared engagement and the firms' provision. It finds large intersectoral variation which cannot be predicted by one factor alone, and sometimes wide intrasectoral variation. In particular (and for different reasons) 'extractive' and 'industrial' sector firms traditionally criticised for their impact on communities - and 'medical' sector firms are engaged in practices conducive to the generation of social capital.Social Capital, Corporate Social Responsibility, Business Ethics, South Africa, Multinational Companies

How do multinationals build social capital? Evidence from Mexico.

This paper looks at the self-reporting of social engagement by multinational firms in Mexico, mapping the configurations of declared engagement. Such social engagements are an important component of how these companies contribute to social capital in the communities within which they operate. We find high performance by some firms, with negligible performance by others. Strong performing sectors include pharmaceuticals & healthcare, other chemical products, and manufacturing. Two case studies - on Alcoa and Schlumberger - detailing different but successful approaches to social capital building are given.social capital, corporate responsibility, business ethics, Mexico, multinational companies

Hydrogen no-vent fill testing in a 5 cubic foot (142 liter) tank using spray nozzle and spray bar liquid injection

A total of 38 hydrogen no-vent fill tests were performed in this test series using various size spray nozzles and a spray bar with different hole sizes in a 5 cubic foot receiver tank. Fill levels of 90 percent by volume or greater were achieved in 26 of the tests while maintaining a receiver tank pressure below 30 psia. Spray nozzles were mounted at the top of the tank, whereas, the spray bar was centered in the tank axially. The spray nozzle no-vent fills demonstrated tank pressure and temperature responses comparable to previous test series. Receiver tank pressure responses for the spray bar configuration were similar to the spray nozzle tests with the pressure initially rising rapidly, then leveling off as vapor condenses onto the discharging liquid streams, and finally ramping up near the end of the test due to ullage compression. Both liquid injection techniques tested were capable of filling the receiver tank to 90 percent under variable test conditions. Comparisons between the spray nozzle and spray bar configurations for well matched test conditions indicate the spray nozzle injection technique is more effective in minimizing the receiving tank pressure throughout a no-vent fill compared to the spray bar under normal gravity conditions