45 research outputs found
GT2010-22151 CHARACTERISTICS OF MULTI-CAVITY TRAPPED VORTEX COMBUSTORS
ABSTRACT This research is motivated towards improving and optimizing the performance of AFRL's Inter-Turbine Burner (ITB) in terms of greater combustion efficiency, reduced losses and exit temperature profile requirements. The ITB is a minicombustor concept, situated in between the high and low pressure turbine stages and typically contains multiple fueled and non-fueled Trapped Vortex Combustor (TVC) cavities. The size, placement, and arrangement of these cavities have tremendous effect on the combustor exit temperature profile. The detailed understanding of the effect of these cavities in a three-dimensional ITB configuration would be very difficult and computationally prohibited. Therefore, a simple but somewhat similar conceptual axi-symmetric burner is used here the design variations of Trapped Vortex Combustor (TVC) through modeling and simulation. The TVC can be one single cavity or can be represented by multi-cavity combustor. In this paper, both single cavity TVC and multi-cavity TVCs are studied. The single cavity TVC is divided into multiple cavities while the total volume of the combustor remains constant. Four combustors are studied: Baseline, Staged, Three-Staged, and Interdigitated TVC. An extensive computational investigation on the characteristics of these multi-cavity TVCs is presented. FLUENT is used for modeling the axisymmetric reacting flow past cavities using a global eddy dissipation mechanism for C 3 H 8 -air combustion with detailed thermodynamic and transport properties. Calculations are performed using Standard, RNG, and Realizable k-Δ RANS turbulence models. The numerical results are validated against experimental temperature measurements on the Base TVC. Results indicate that the pressure drag is the major contributor to total drag in the Base TVC. However, viscous drag is still significant. By adding a concentric cavity in sequential manner (i.e. Staged TVC), the pressure drag decreases, whereas the viscous drag remains nearly constant. Further addition of a secondary concentric cavity (i.e. Three-Staged TVC), the total drag does not further decrease and both pressure and viscous drag contributions do not change. If instead a non-concentric cavity is added to the Base TVC (i.e. Interdigitated TVC), the pressure drag increases while the viscous drag decreases slightly. The effect of adding swirl flow is to increase the fuel-air mixing and as a result, it increases the maximum exit temperature for all the combustors modeled. The jets and heat release contribute to increase pressure drag with the former being greater. The fuel and air jets and heat release also modify the cavity flow structure. By turning off the fuel and air jets in the Staged TVC, lower drag (or pressure loss) and exit temperature are achieved. It is more effective to turn off the fuel and air jets in the upstream (front) cavity in order to reduce pressure losses. Based on these results, recommendations are provided to the engineer/designer/modeler to improve the performance of the ITB
γΎ T lymphocytes in the diagnosis of human T cell receptor immunodeficiencies
Supported by grants from MINECO (SAF 2011-24235, BES-2012-055054, SAF2014- 54708-R, and SAF2014-53563-REDT) CAM (S2010/BMD-2316) ISCIII (RD08- 0075-0002 and PI12/02761)Peer Reviewe
Probing the Star Formation Main Sequence down to M at
We investigate the star formation main sequence (MS) (SFR-M) down
to 10 using a sample of 34,061 newly-discovered
ultra-faint ( mag) galaxies at detected in
the GOODS-N field. Virtually these galaxies are not contained in previous
public catalogs, effectively doubling the number of known sources in the field.
The sample was constructed by stacking the optical broad-band observations
taken by the HST/GOODS-CANDELS surveys as well as the 25 ultra-deep medium-band
images gathered by the GTC/SHARDS project. Our sources are faint (average
observed magnitudes mag, mag), blue (UV-slope
), star-forming (rest-frame colors mag,
mag) galaxies. These observational characteristics are
identified with young (mass-weighted age Gyr)
stellar populations subject to low attenuations (
mag). Our sample allows us to probe the MS down to
at and at , around 0.6 dex deeper than
previous analysis. In the low-mass galaxy regime, we find an average value for
the slope of 0.97 at and 1.12 at . Nearly 60% of our
sample presents stellar masses in the range M between
. If the slope of the MS remained constant in this regime, the sources
populating the low-mass tail of our sample would qualify as starburst galaxies.Comment: 34 pages, 16 figures, 9 tables. Accepted for publication to Ap
Realâworld evidence of tisagenlecleucel for the treatment of relapsed or refractory large Bâcell lymphoma
Tisagenlecleucel (tisa-cel) is a second-generation autologous CD19-targeted chimeric antigen receptor (CAR) T-cell therapy approved for relapsed/refractory (R/R) large B-cell lymphoma (LBCL). The approval was based on the results of phase II JULIET trial, with a best overall response rate (ORR) and complete response (CR) rate in infused patients of 52% and 40%, respectively. We report outcomes with tisa-cel in the standard-of-care (SOC) setting for R/R LBCL. Data from all patients with R/R LBCL who underwent leukapheresis from December 2018 until June 2020 with the intent to receive SOC tisa-cel were retrospectively collected at 10 Spanish institutions. Toxicities were graded according to ASTCT criteria and responses were assessed as per Lugano 2014 classification. Of 91 patients who underwent leukapheresis, 75 (82%) received tisa-cel therapy. Grade 3 or higher cytokine release syndrome and neurotoxicity occurred in 5% and 1%, respectively; non-relapse mortality was 4%. Among the infused patients, best ORR and CR were 60% and 32%, respectively, with a median duration of response of 8.9 months. With a median follow-up of 14.1 months from CAR T-cell infusion, median progression-free survival and overall survival were 3 months and 10.7 months, respectively. At 12 months, patients in CR at first disease evaluation had a PFS of 87% and OS of 93%. Patients with an elevated lactate dehydrogenase showed a shorter PFS and OS on multivariate analysis. Treatment with tisa-cel for patients with relapsed/refractory LBCL in a European SOC setting showed a manageable safety profile and durable complete responses
Global data on earthworm abundance, biomass, diversity and corresponding environmental properties
Publisher Copyright: © 2021, The Author(s).Earthworms are an important soil taxon as ecosystem engineers, providing a variety of crucial ecosystem functions and services. Little is known about their diversity and distribution at large spatial scales, despite the availability of considerable amounts of local-scale data. Earthworm diversity data, obtained from the primary literature or provided directly by authors, were collated with information on site locations, including coordinates, habitat cover, and soil properties. Datasets were required, at a minimum, to include abundance or biomass of earthworms at a site. Where possible, site-level species lists were included, as well as the abundance and biomass of individual species and ecological groups. This global dataset contains 10,840 sites, with 184 species, from 60 countries and all continents except Antarctica. The data were obtained from 182 published articles, published between 1973 and 2017, and 17 unpublished datasets. Amalgamating data into a single global database will assist researchers in investigating and answering a wide variety of pressing questions, for example, jointly assessing aboveground and belowground biodiversity distributions and drivers of biodiversity change.Peer reviewe
Recommended from our members
Global data on earthworm abundance, biomass, diversity and corresponding environmental properties
Earthworms are an important soil taxon as ecosystem engineers, providing a variety of crucial ecosystem functions and services. Little is known about their diversity and distribution at large spatial scales, despite the availability of considerable amounts of local-scale data. Earthworm diversity data, obtained from the primary literature or provided directly by authors, were collated with information on site locations, including coordinates, habitat cover, and soil properties. Datasets were required, at a minimum, to include abundance or biomass of earthworms at a site. Where possible, site-level species lists were included, as well as the abundance and biomass of individual species and ecological groups. This global dataset contains 10,840 sites, with 184 species, from 60 countries and all continents except Antarctica. The data were obtained from 182 published articles, published between 1973 and 2017, and 17 unpublished datasets. Amalgamating data into a single global database will assist researchers in investigating and answering a wide variety of pressing questions, for example, jointly assessing aboveground and belowground biodiversity distributions and drivers of biodiversity change
Performance levels of four Latin American laboratories for the serodiagnosis of Chagas disease in Mexican sera samples
A numerical study of stabilization and emission characteristics of triple flames.
A numerical study of stabilization and emission characteristics of triple flames