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Raval, Manan

Publications and source records attributed to Raval, Manan.

Granular Temperature Modeling with Large-Scale CFD-DEM Data

The granular temperature is a measure of solids-phase fluctuating kinetic energy in particle-laden gas-solid flows. This report focuses on reduced-order models of granular temperature in triply-periodic cluster induced turbulent flow. The granular temperature data was generated by post-processing large-scale CFD-DEM simulations that were carried out as part of an ALCC awarded study. The algebraic model of Tang et al, originally fit to DNS data, was found to be amenable to the present data. The results of several regression analyses are presented building on the original expression. This work was performed in part through the National Nuclear Security Administration (NNSA) Minority Serving Institutions Internship Program (MSIIP).

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Tunable Diode Laser Absorption Spectroscopy Using a Multi-Pass White Cell for O 2 Detection

Two forms of Tunable Diode Laser Absorption Spectroscopy (TDLAS), direct absorbance spectroscopy and wavelength modulation spectroscopy (WMS), for O 2 detection were carried out using a tunable 763-nm vertical cavity surface emitting laser (VCSEL) in a multi-pass White cell with an optical path length of 2.6 m. The cell was fitted with a gas flow mechanism for concentration studies. The output wavelength of the tunable VCSEL was increased by ramping the drive current from 0-5 mA while temperature controlling the device to 20 °C. The output wavelength of the VCSEL was mapped using a spectrum analyzer.

42 ENGINEERING↗