Subsonic Swept Fan Blade

A gas turbine engine includes a spool, a turbine coupled to drive the spool, a propulsor coupled to be driven at a at a design speed by the turbine through the spool, and a gear assembly coupled between the propulsor and the spool. Rotation of the turbine drives the propulsor at a different speed than the spool. The propulsor includes a hub and a row of propulsor blades that extend from the hub. Each of the propulsor blades includes an airfoil body. The leading edge of the airfoil body has a swept profile such that, at the design speed, a component of a relative velocity vector of a working gas that is normal to the leading edge is subsonic along the entire radial span

Efficient, Low Pressure Ratio Propulsor for Gas Turbine Engines

A gas turbine engine includes a bypass flow passage that has an inlet and defines a bypass ratio in a range of approximately 8.5 to 13.5. A fan is arranged within the bypass flow passage. A first turbine is a 5-stage turbine and is coupled with a first shaft, which is coupled with the fan. A first compressor is coupled with the first shaft and is a 3-stage compressor. A second turbine is coupled with a second shaft and is a 2-stage turbine. The fan includes a row of fan blades that extend from a hub. The row includes a number (N) of the fan blades, a solidity value (R) at tips of the fab blades, and a ratio of N/R that is from 14 to 16

Efficient, Low Pressure Ratio Propulsor for Gas Turbine Engines

A gas turbine engine includes a spool, a turbine coupled to drive the spool, and a propulsor that is coupled to be driven by the turbine through the spool. A gear assembly is coupled between the propulsor and the spool such that rotation of the turbine drives the propulsor at a different speed than the spool. The propulsor includes a hub and a row of propulsor blades that extends from the hub. The row includes no more than 20 of the propulsor blades

Rotor with Flattened Exit Pressure Profile

A rotor blade comprises an airfoil extending radially from a root section to a tip section and axially from a leading edge to a trailing edge, the leading and trailing edges defining a curvature therebetween. The curvature determines a relative exit angle at a relative span height between the root section and the tip section, based on an incident flow velocity at the leading edge of the airfoil and a rotational velocity at the relative span height. In operation of the rotor blade, the relative exit angle determines a substantially flat exit pressure ratio profile for relative span heights from 75% to 95%, wherein the exit pressure ratio profile is constant within a tolerance of 10% of a maximum value of the exit pressure ratio profile

Crucible of the Civil War: Virginia from Secession to Commemoration

Crucible of the Civil War offers an illuminating portrait of the state’s wartime economic, political, and social institutions. Weighing in on contentious issues within established scholarship while also breaking ground in areas long neglected by scholars, the contributors examine such concerns as the war’s effect on slavery in the state, the wartime intersection of race and religion, and the development of Confederate social networks. They also shed light on topics long disputed by historians, such as Virginia’s decision to secede from the Union, the development of Confederate nationalism, and how Virginians chose to remember the war after its close.https://scholarship.richmond.edu/bookshelf/1258/thumbnail.jp

Dear Wife : the Civil War letters of Chester K. Leach

Occasional paper (University of Vermont. Center for Research on Vermont) ; no. 20

Efficient, Low Pressure Ratio Propulsor for Gas Turbine Engines

A gas turbine engine includes a gear assembly and a bypass flow passage that includes an inlet and an outlet that define a design pressure ratio between 1.3 and 1.55. A fan is arranged at the inlet. A first turbine is coupled with a first shaft such that rotation of the first turbine will drive the fan, through the first shaft and the gear assembly, at a lower speed than the first shaft. The fan includes a row of fan blades. The row includes 12-16 (N) fan blades, a solidity value (R) that is from 1.0 to 1.3, and a ratio of N/R that is from 10.0 to 16

Efficient, Low Pressure Ratio Propulsor for Gas Turbine Engines

A gas turbine engine includes a core flow passage, a bypass flow passage, and a propulsor arranged at an inlet of the bypass flow passage and the core flow passage. The propulsor includes a row of propulsor blades. The row includes no more than 20 of the propulsor blades. The propulsor has a pressure ratio between about 1.2 and about 1.7 across the propulsor blades

Gender and Racial/Ethnic Disparities: Cumulative Screening of Health Risk Indicators in 20-50 Year Olds in the United States

This study explored potential gender and racial/ethnic disparities in overall health risk related to 24 health risk indicators selected across six domains: socioeconomic, health status and health care, lifestyle, nutritional, clinical, and environmental. Using the 2003-2006 National Health and Nutrition Examination Surveys (NHANES), it evaluated cross-sectional data for 5,024 adults in the United States. Logistic regression models were developed to estimate prevalence odds ratios (PORs) adjusted for smoking, health insurance status, and age. Analyses evaluated disparities associated with 24 indicator variables of health risk, comparing females to males and four racial/ethnic groups to non-Hispanic Whites. Non-Hispanic Blacks and Mexican Americans were at greater risk for at least 50% of the 24 health risk indicators, including measures of socioeconomic status, health risk behaviors, poor/fair self-reported health status, multiple nutritional and clinical indicators, and blood lead levels. This demonstrates that cumulative health risk is unevenly distributed across racial/ethnic groups. A similarly high percentage (46%) of the risk factors was observed in females. Females as compared to males were more likely to have lower income, lower blood calcium, poor/fair self-reported health, more poor mental health days/month, higher medication usage and hospitalizations, and higher serum levels of some clinical indicators and blood cadmium. This analysis of cumulative health risk is responsive to calls for broader-based, more integrated assessment of health disparities that can help inform community assessments and public health policy