33 research outputs found
sj-zip-1-pie-10.1177_09544089221117142 - Supplemental material for Entropy production analysis and cooling time calculation for an open hemispherical cavity in natural convection
No full textSupplemental material, sj-zip-1-pie-10.1177_09544089221117142 for Entropy production analysis and cooling time calculation for an open hemispherical cavity in natural convection by Bismaya Ranjan Behera, Vikrant Chandrakar, Arnab Mukherjee and Jnana Ranjan Senapati in Proceedings of the Institution of Mechanical Engineers, Part E: Journal of Process Mechanical Engineering</p
Securitization and mortgage default
No full textThe academic literature, the popular press, and policymakers have all debated securitization's contribution to the poor performance of mortgages originated in the run-up to the recent crisis. Theoretical arguments have been advanced on both sides, but the lack of suitable data has made it difficult to assess them empirically. The author examines this issue by using a loan-level data set from LPS Analytics, covering approximately two-thirds of the mortgages originated in 2005 and 2006, and including both securitized and nonsecuritized loans. ; The author finds evidence that privately securitized loans do indeed perform worse than observably similar, nonsecuritized loans. Moreover, this effect is strongest in prime mortgage markets, which have not been studied in the previous literature. For example, a typical prime loan becomes delinquent at a 20 percent higher rate if it is privately securitized, ceteris paribus. This is consistent with the existence of adverse selection; that is, that lenders used information not available to investors to securitize loans that were riskier than they otherwise appeared. By contrast, for subprime mortgages, the impact of private securitization is concentrated in low or no-documentation loans; this latter result is consistent with previous work such as Keys et al. (2009).Mortgage-backed securities ; Default (Finance)
Conjugate Natural Convection with Surface Radiation from Different Infrared Suppression (IRS) Systems
No full textThe naval ships, warships, and merchant ships are equipped with infrared suppression (IRS) systems for easy operation in the deep ocean. The IRS device reduces the temperature of hot exhaust products, which will help in stealth technology so that infrared gadgets cannot detect ships or aircraft. The cooling of the IRS system is an important aspect, and the current research deals with the numerical investigation of various IRS systems, namely, cylindrical funnel, IRS with multiple cylindrical and conical funnels, louvered cylindrical funnel, louvered conical funnel, and conical funnel. This research primarily aims to obtain thermo-fluid characteristics from the mentioned IRS systems due to conjugate heat transfer with the combined effect of natural convection and surface radiation. In addition, the time required to cool down the hot IRS system to atmospheric temperature is also estimated using the lumped-capacitance method. For the numerical analysis, different governing equations (Navier-Stokes equation, turbulence equation (− equation), energy equation, and radiation equation) are solved using the finite volume method (FVM) based solver of ANSYS Fluent 15.0. Initially, the preliminary work is carried out on the vertical hollow cylinder with a finite thickness of different aspect ratios to observe the combined effect of convection and surface radiation. Results show that including surface radiation in the net heat transfer rate estimation is significant and should not be ignored. The research is further extended for the IRS system with multiple cylindrical and conical funnels. To perform the analysis, different parameters such as the number of funnels, Rayleigh number, inner surface temperature, geometric ratio (GR), funnel overlapping, and surface emissivity are varied to elucidate the heat transfer behavior. The results of the IRS system with cylindrical funnels show that the total heat transfer rate rises with the number of funnels. Both non-dimensional induced mass flow rate and total heat transfer rate have maximum value for zero overlapping cases irrespective of funnel numbers. In contrast, it decreases for both negative and positive overlapping. At constant temperature contribution of radiative heat transfer varies from 10 to 38% with the rise in emissivity. In the case of a conical funneled IRS system, an increase in geometric ratio enhances the mass suction and total heat transfer rate with funnel numbers for the considered temperature range. At a constant temperature, the total heat transfer increases up to 4.9 times when GR varies from 1 to 1.3 for six funneled systems. Convective heat transfer’s relative strength rises with Rayleigh number, whereas the relative strength of radiative heat transfer drops. However, radiative heat transfer contributes up to 63% of total heat transfer for fixed GR and funnels. The convective heat transfer is always higher than radiative heat transfer for IRS with multiple funnels; therefore, radiative heat transfer contribution weakens with increased funnels for all considered emissivities, whereas the convective heat transfer contribution augments. Furthermore, the thermodynamic characterization of IRS with multiple cylindrical funnels subjected to natural convection alone is carried out. The Bejan number decreases with the Rayleigh number and geometric ratio. As the number of funnels rises, the increment in heat transfer irreversibility is much lesser than the fluid friction irreversibility, resulting in a continuous decrease in the Bejan number. In the case of a cylindrical louvered funnel, some geometrical parameters like the number of holes in each row (6 to 14), number of rows of louvers (2 to 8), and shapes of holes are also varied in addition to Rayleigh number, surface temperature, and surface emissivity. The results indicate that the Nusselt number and mass suction ratio increases with the number of rows of holes and the number of holes in each row. The Nusselt number is highest for the funnel with circular holes, whereas the lowest is for triangular holes. Moreover, results show that the surface radiation contribution is significant even at low emissivity. Furthermore, the research is extended towards the three-dimensional comparative study of the IRS system made up of a single cylindrical louvered funnel, conical louvered funnel, cylindrical funnel, and conical funnel. The mass suction ratio and total Nusselt number increase with the wall temperature of the surface linearly. The conical funnel gives the least total Nusselt number, and the cylindrical louvered funnel gives the highest. Moreover, thermodynamic analysis of these funnels is also conducted, and results reveal that the cylindrical louvered funnel outperforms the rest of the considered funnel in terms of heat transfer rate, increasing with surface temperature and Rayleigh number. A performance evaluation criterion (ratio of irreversibility to heat transfer) is described for the performance of different funnels, and results indicated that it decreases with Rayleigh number, indicating that the rise in heat transfer becomes much more than the rise in irreversibility at high Rayleigh. Also, the time-temperature graph shows that the louvered cylindrical funnel cools the fastest while the louvered conical funnel is the slowest. To visualize the thermo-fluid behavior around the IRS system and its near surrounding various temperature contours, velocity vector plots, velocity contours, and entropy generation contours for different cases are also provided for better understanding
Role of Risk Stratification and Genetics in Sudden Cardiac Death
No full textSudden cardiac death (SCD) is a major public health issue due to its increasing incidence in the general population and the difficulty in identifying high-risk individuals. Nearly 300,000-350,000 patients in the United States and 4- to 5 million patients in the world die from SCD. Coronary artery disease and advanced heart failure are the main etiology for SCD. Ischemia of any cause precipitates lethal arrhythmias, and ventricular tachycardia and ventricular fibrillation are the most common lethal arrhythmias precipitating SCD. Pulse-less electrical activity, brady-arrhythmia and electromechanical dissociation also result in SCD. Most sudden cardiac deaths occur out-of-the-hospital setting, so it is difficult to estimate the public burden, which results in overestimating the incidence of SCD. The insufficiency and limited predictive value of various indicators and criteria for SCD result in the increasing incidences. As a result, there is a need to develop better risk stratification criteria and find modifiable variables to decrease the incidence. Primary and secondary prevention and treatment of SCD need further research. This critical review is focused on the etiology, risk factors, prognostic factors and importance of risk stratification of SCD.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author
Analysis and Design of Solar Dryer for Forest Produce of Bastar Region in State of Chhattisgarh, India
No full textTo analyze the different popular design of low-pressure acetylene gas welding generators in India
No full text
A novel approach to MP-PIC: Continuum particle model for dense particle flows in fluidized beds
No full textA novel approach to Multiphase-Particle-in-Cell (MP-PIC), called Continuum Particle Model (CPM), is developed for dense gas-particle flows. CPM has high computational speed, comparable to that of MP-PIC, but a robustness and accuracy closer to that of a Discrete Element Model (DEM). The gas phase is treated as a continuum phase and particles are tracked discretely, but particle collisions are modelled by considering the divergence of the continuum particle stress tensor. Details on efficient solution to the model are presented. For comparison, a parametric study is performed for quasi-2D fluidized beds. Comparison of CFD-CPM is made with MP-PIC and CFD-DEM. The particle stress models by Harris and Crighton, and by Srivastava and Sundaresan are tested in our CFD-CPM. Results from CFD-CPM based on the Srivastava and Sundaresan particle stress model show good agreement with CFD-DEM results. We validate our model by comparison with experimental benchmark results from Gopalan et. al. (2016).Complex Fluid Processin
Extraction of Phenol from Aqueous Effluents using Supported Liquid Membrane
No full textThis Dissertation / Report is the outcome of investigation carried out by the creator(s) / author(s) at the department/division of Central Food Technological Research Institute (CFTRI), Mysore mentioned below in this page
