Cavitating Jet Method and System for Oxygenation of Liquids

Reclamation and re-use of water is critical for space-based life support systems. A number of functions must be performed by any such system including removal of various contaminants and oxygenation. For long-duration space missions, this must be done with a compact, reliable system that requires little or no use of expendables and minimal power. DynaJets cavitating jets can oxidize selected organic compounds with much greater energy efficiency than ultrasonic devices typically used in sonochemistry. The focus of this work was to develop cavitating jets to simultaneously accomplish the functions of oxygenation and removal of contaminants of importance to space-structured water reclamation systems. The innovation is a method to increase the concentration of dissolved oxygen or other gasses in a liquid. It utilizes a particular form of novel cavitating jet operating at low to moderate pressures to achieve a high-efficiency means of transporting and mixing the gas into the liquid. When such a jet is utilized to simultaneously oxygenate the liquid and to oxidize organic compounds within the liquid, such as those in waste water, the rates of contaminant removal are increased. The invention is directed toward an increase in the dissolved gas content of a liquid, in general, and the dissolved oxygen content of a liquid in particular

Simulation studies of improved sounding systems

Two instrument designs for indirect satellite sounding of the atmosphere in the infrared are represented by the High Resolution Infra-Red Sounder, Model 2 (HIRS-2) and by the Advanced Meteorological Temperature Sounder (AMTS). The relative capabilities of the two instruments were tested by simulating satellite measurements from a group of temperature soundings, allowing the two participants to retrieve the temperature profiles from the simulated data, and comparing the results with the original temperature profiles. Four data sets were produced from radiosondes data extrapolated to a suitable altitude, representing continents and oceans, between 30S and 30N. From the information available, temperature profiles were retrieved by two different methods, statistical regression and inversion of the radiative transfer equation. Results show the consequence of greater spectral purity, concomitant increase in the number of spectral intervals, and the better spatial resolution in partly clouded areas. At the same time, the limitation of the HIRS-2 without its companion instrument leads to some results which should be ignored in comparing the two instruments. A clear superiority of AMTS results is shown

The influence of tropospheric biennial oscillation on mid-tropospheric CO_2

Mid-tropospheric CO_2 retrieved from the Atmospheric Infrared Sounder (AIRS) was used to investigate CO_2 interannual variability over the Indo-Pacific region. A signal with periodicity around two years was found for the AIRS mid-tropospheric CO_2 for the first time, which is related to the Tropospheric Biennial Oscillation (TBO) associated with the strength of the monsoon. During a strong (weak) monsoon year, the Western Walker Circulation is strong (weak), resulting in enhanced (diminished) CO_2 transport from the surface to the mid-troposphere. As a result, there are positive (negative) CO2 anomalies at mid-troposphere over the Indo-Pacific region. We simulated the influence of the TBO on the mid-tropospheric CO_2 over the Indo-Pacific region using the MOZART-2 model, and results were consistent with observations, although we found the TBO signal in the model CO_2 is to be smaller than that in the AIRS observations

Capture and inception of bubbles near line vortices

Motivated by the need to predict vortex cavitation inception, a study has been conducted to investigate bubble capture by a concentrated line vortex of core size rcrc and circulation Γ0Γ0 under noncavitating and cavitating conditions. Direct numerical simulations that solve simultaneously for the two phase flow field, as well as a simpler one-way coupled point-particle-tracking model (PTM) were used to investigate the capture process. The capture times were compared to experimental observations. It was found that the point-particle-tracking model can successfully predict the capture of noncavitating small nuclei by a line vortex released far from the vortex axis. The nucleus grows very slowly during capture until the late stages of the process, where bubble/vortex interaction and bubble deformation become important. Consequently, PTM can be used to study the capture of cavitating nuclei by dividing the process into the noncavitating capture of the nucleus, and then the growth of the nucleus in the low-pressure core region. Bubble growth and deformation act to speed up the capture process.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/87832/2/022105_1.pd

The Mechanical Energies of the Global Atmosphere in El Niño and La Niña Years

Two meteorological reanalysis datasets are analyzed to determine the mechanical energies of the global atmosphere in the El Niño and La Niña years. The general consistency of the mean energy components between the two datasets reveals ~1%–3% increase and ~2%–3% decrease in the mean energies in the El Niño years and La Niña years, respectively. These analyses further reveal that the tropospheric temperature responds to the sea surface temperature anomaly with a time lag of two months, which leads to the varying mean atmospheric energies in the El Niño and La Niña years

FEDSM2003-45310 DEVELOPMENT OF A NEAR REAL-TIME INSTRUMENT FOR NUCLEI MEASUREMENT: THE ABS ACOUSTIC BUBBLE SPECTROMETER

ABSTRACT The ABS Acoustic Bubble Spectrometer (ABS) is an acoustics based device that measures bubble size distributions and void fractions in liquids using the properties of acoustic wave propagation through a two-phase medium. The ABS is PC-based and uses software that controls signal generation, detection and signal processing through data boards and two hydrophones. The data is processed and analyzed utilizing inverse problem solution algorithms to obtain the bubble size distribution. All physical, experimental, and analytical parameters are input by the user via a series of dialog boxes. The results are displayed graphically by the interface in real time and can also be stored or printed. In this paper we describe the method and present validation experiments that compare bubble distributions and void fraction results of ABS measurements with optical measurements in the laboratory. The two methods give very close results with the ABS possessing the significant advantage of enabling near real-time measurements with the potential to become an on-line measuring device

CO_2 semiannual oscillation in the middle troposphere and at the surface

Using in situ measurements, we find a semiannual oscillation (SAO) in the midtropospheric and surface CO_2. Chemistry transport models (2-D Caltech/JPL model, 3-D GEOS-Chem, and 3-D MOZART-2) are used to investigate possible sources for the SAO signal in the midtropospheric and surface CO_2. From model sensitivity studies, it is revealed that the SAO signal in the midtropospheric CO_2 originates mainly from surface CO_2 with a small contribution from transport fields. It is also found that the source for the SAO signal in surface CO_2 is mostly related to the CO_2 exchange between the biosphere and the atmosphere. By comparing model CO_2 with in situ CO_2 measurements at the surface, we find that models are able to capture both annual and semiannual cycles well at the surface. Model simulations of the annual and semiannual cycles of CO_2 in the tropical middle troposphere agree reasonably well with aircraft measurements

Design of Educational Material and Public Awareness Campaigns for Improving Work Zone Driver Safety

This project aims to help improve work zone driver safety in Indiana through driver education and public awareness campaigns. The project focused on two specific objectives: (1) to design a public awareness campaign to increase drivers’ knowledge and influence positive attitudes about work zone driver safety practices; and (2) to prepare educational materials to be incorporated into driver’s education or training curriculum prior to taking driving test and getting a driver’s license issued. The campaign was informed by formative research, conducted using a survey to assess public knowledge and attitudes. Based on these results, campaign messages were designed. The team also designed an education curriculum which consists of three modules and fourteen knowledge questions. This report concludes with recommendations to INDOT for the successful implementation of the public awareness campaign and educational materials, that might be applicable to other states as well