Control of flow separation and mixing by aerodynamic excitation

The recent research in the control of shear flows using unsteady aerodynamic excitation conducted at the NASA Lewis Research Center is reviewed. The program is of a fundamental nature, concentrating on the physics of the unsteady aerodynamic processes. This field of research is a fairly new development with great promise in the areas of enhanced mixing and flow separation control. Enhanced mixing research includes influence of core turbulence, forced pairing of coherent structures, and saturation of mixing enhancement. Separation flow control studies included are for a two-dimensional diffuser, conical diffusers, and single airfoils. Ultimate applications include aircraft engine inlet flow control at high angle of attack, wide angle diffusers, highly loaded airfoils as in turbomachinery, and ejector/suppressor nozzles for the supersonic transport. An argument involving the Coanda Effect is made that all of the above mentioned application areas really only involve forms of shear layer mixing enhancement. The program also includes the development of practical excitation devices which might be used in aircraft applications

Accident prevention in cement plants

The cement industry as a whole took up accident prevention work along with the pioneers. With the organization of the Portland Cement Association, a Bureau of Accident Prevention was formed. This Accident Prevention Bureau, by sending out literature, holding competitions, collecting and tabulating results of accidents collected from every cement manufacturer and affiliating with National Safety Council as the Cement Section, has made rapid strides each year, until today it is doubtful if any other branch of manufacturers can show more improvement in accident records than the cement industry. In spite of their marked improvements each year, there were 47 fatal accidents in the cement industry in 1922, which shows that there is still room for improvement --page 3

Inlets, ducts, and nozzles

The internal fluid mechanics research program in inlets, ducts, and nozzles consists of a balanced effort between the development of computational tools (both parabolized Navier-Stokes and full Navier-Stokes) and the conduct of experimental research. The experiments are designed to better understand the fluid flow physics, to develop new or improved flow models, and to provide benchmark quality data sets for validation of the computational methods. The inlet, duct, and nozzle research program is described according to three major classifications of flow phenomena: (1) highly 3-D flow fields; (2) shock-boundary-layer interactions; and (3) shear layer control. Specific examples of current and future elements of the research program are described for each of these phenomenon. In particular, the highly 3-D flow field phenomenon is highlighted by describing the computational and experimental research program in transition ducts having a round-to-rectangular area variation. In the case of shock-boundary-layer interactions, the specific details of research for normal shock-boundary-layer interactions are described. For shear layer control, research in vortex generators and the use of aerodynamic excitation for enhancement of the jet mixing process are described

Inlets, ducts and nozzles

The internal fluid mechanics research program in inlets, ducts, and nozzles is described. The program consists of a balanced effort between the development of computational tools and the conduct of experimental research. The experiments are designed to better understand the fluid flow physics, to develop new or improved flow models, and to provide benchmark quality data sets for validation of the computational methods. The inlet, duct, and nozzle research program is described according to three major classifications of flow phenomena: highly three-dimensional flow fields; shock-boundary layer interactions; and shear layer control. Specific examples of current and future elements of the research program are described for each of these phenomena. In particular, the highly three-dimensional flow field phenomena is highlighted by describing the computational and experiemental research program in transition ducts having a round-to-rectangular area variation. In the case of shock-boundary layer interactions, the specific details of research for normal shock-boundary layer interactions are described. For shear layer control research in vortex generators and the use of aerodynamic excitation for enhancement of the jet mixing process are described. Future research in inlets, ducts, and nozzles will include more emphasis on three-dimensional full Navier-Stokes methods and corresponding experiments designed to concentrate on the appropriate three-dimensional fluid flow physics

The Neighborhood’s Catalogue: Lower East Side Planning and Design File

This catalogue was designed to support the process of slow redevelopment over time, combined with conservation of diverse social and historical continuity and the exploration of new land and building uses. The catalogue shows how to involve neighborhoods in participation, supportive design, incremental planning and phased development. This project was made possible by a grant from the National Endowment for the Arts. Reprinted in 1987.https://dc.uwm.edu/caupr_mono/1047/thumbnail.jp

Mega Tsunami of the World Oceans: Chevron Dune Formation, Micro-Ejecta, and Rapid Climate Change as the Evidence of Recent Oceanic Bolide Impacts

This paper deals with the physical and environmental effects resulting from oceanic impacts by sizable comets, and the rates and risks associated with such cosmic impacts. Specifically, we investigate two sets of probable oceanic impact events that occurred within the last 5,000 years, one in the Indian Ocean about 2800 BC, and the other in the Gulf of Carpentaria (Australia) about AD 536. If validated, they would be the most energetic natural catastrophes occurring during the middle-to-late Holocene with large-scale environmental and historical human effects and consequences. The physical evidence for these two impacts consists of several sets of data: (1) remarkable depositional traces of coastal flooding in dunes (chevron dunes) found in southern Madagascar and along the coast of the Gulf of Carpentaria, (2) the presence of crater candidates (29-km Burckle crater about 1,500 km southeast of Madagascar which dates to within the last 6,000 years and 18-km Kanmare and 12-km Tabban craters with an estimated age of AD 572±86 in the southeast corner of the Gulf of Carpentaria), and (3) the presence of quench textured magnetite spherules and nearly pure carbon spherules, teardrop-shaped tektites with trails of ablation, and vitreous material found by cutting-edge laboratory analytical techniques in the upper-most layer of core samples close to the crater candidates. Although some propose a wind-blown origin for V-shaped chevron dunes that are widely distributed around the coastlines of the Indian Ocean and in the Gulf of Carpentaria, we have evidence in favor of their mega tsunami formation. In southern Madagascar we have documented evidence for tsunami wave run-up reaching 205 m above sea-level and penetrating up to 45 km inland along the strike of the chevron axis. Subtly the orientation of the dunes is not aligned to the prevailing wind direction, but to the path of refracted mega-tsunami originating from Burckle impact crater. The results of our study show that substantive oceanic comet impacts not only have occurred more recently than modeled by astrophysicists, but also that they have profoundly affected Earth’s natural systems, climate, and human societies. If validated, they could potentially lead to a major paradigm shift in environmental science by recognizing the role of oceanic impacts in major climate downturns during the middle-to-late Holocene that have been well documented already by different techniques (tree-ring anomalies, ice-, lake- and peat bog-cores)

Meteorology records and analysis of the observatory records for July 1866 in conjunction with those of births and deaths

Meteorological records recorded at the Observatory, Hobart Town. Includes the leafing, flowering, and fruiting of a few standard plants in the Royal Society's Gardens during the month of July 1866. The meteorological phenomena of this July have been so nicely balanced in their effects on life, that the deaths were only one below the average of the nine previous Julys. In 1865,—the healthiest July on record, —the mortality was one-third lower; nevertheless, it is remarkable, that the present month had a smaller number of deaths under 45 years of age, than any one of the preceding nine years, the death-rate being raised, altogether, by very infirm and old people. The weather, still, was quite abnormal, as the following analysis will show

Meterology records and notes on the mortality of the Hobart town registration district during the month of February, 1872.

Meteorological records recorded at the Observatory, Hobart Town. Includes leafing, flowering, and fruiting of a few standard plants in the Royal Society's Gardens during the month of February, 1872. Warm days, cold nights, numerous and gentle sea breezes with plenty of ozone, nearly an average of rain-fall, but mostly precipitated on two days, five days apart, though with atmospheric pressure high and variable, and temperature above the average, was conducive to the health of the community above five years old, the deaths at all ages being considerably less than the average of the previous 15 years