Thirumoolar's Educational Policies

Saivism is one of the oldest religions in our country. The Saiva saints gave ‘Panniru Thirumuraikal (Thirumurai is a twelve-volume compendium of songs or hymns in praise of Shiva)’ to instill in the minds of the people of the world the feeling of God. Thirumanthiram by Thirumoolar is the 10th Thirumarai among the religious books of such a special Thirumarai Panuval (Thirumurai Discourses). Thirumoolar has created a book that explains the good life, the system, and the subtleties of Jnana Yoga (The Path of attaining Knowledge) for all the people of the world to undertake. In Thirumanthiram, Thirumoolar has effectively laid down the principles of education, questioning, and illiteracy for the well-being of the people of the country. Education is the basis of the principle of individual morality. Education is something that enables an individual to excel in life. Education has the power to change society. If every human being is to have good discipline, there must be education. That is why our great sages have emphasized the importance of education in their books. Thirumoolar, a Saiva devotee, has also explained the education of individual life in Thirumanthiram. He has emphasized the significance of wisdom education in enabling man to live as a human being. This thesis explains the educational principles that Thirumoolar proposed for the betterment of individual lives

Co-treatment of benzene and toluene vapours in a biofilter: A factorial design approach

[Abstract] Biofiltration has now become an indispensable treatment technique for the removal of low concentrations of Volatile Organic Compounds (VOCs) from process vent streams. This study involves performance evaluation of a laboratory scale compost based biofilter for the treatment of mixtures of benzene and toluene (BT) vapours. Experiments were conducted as per a statistical design of experiment, the 2k full factorial design, with the initial concentrations of benzene and toluene and the gas flow rate as the independent variables and the elimination capacity (EC) and removal efficiency (RE) as response variables. The maximum EC attained was 31.7 g/m3.h for benzene and 85.9 g/m3.h for toluene, while the total maximum EC at an inlet loading rate (ILR) of 150.2 g/m3.h was 91.2 g/m3.h. It was also observed that while there was mutual inhibition, benzene removal was severely inhibited by the presence of toluene than toluene removal by the presence of benzene. Statistical analysis in the form of analysis of variance (ANOVA) was carried out to determine the main and interaction effects of variables on the RE and EC values. This study establishes the potential application of biofilters to handle mixtures of VOCs effectively through a statistically authentic approach

Dichloromethane removal using mixed cultures in a biofilter and a modified rotating biological contactor -start up studies

[Abstract] Dichloromethane (DCM) is a widely used organic solvent which is considered to be hazardous air pollutant. Regulatory standards in many countries require its removal from waste gas streams. Biological waste gas treatment is an attractive and environmental-friendly alternative to physicochemical methods. Volatile organic compounds (VOCs) in waste gases can serve as energy source and/or carbon source for the microbial metabolism. Biofilters and biotrickling filters, the widely used bioreactors, suffer from limitations such as control of operating parameters, pH, humidity and nutrient supply and clogging due to overgrowth of biofilm. To overcome these drawbacks, a modified rotating biological contactor (RBC) has been proposed which can retain the advantages of conventional systems. A conventional RBC system containing 20 acrylic discs 21 cm diameter and 5mm thickness with a disc spacing of 10 mm was modified by adding a leak tight cover and baffles between disks to avoid short circuiting of flow. The biofilm was formed on the discs with inoculum pre acclimatized to DCM at low concentration. The RBC was operated at an inlet concentration of 0.15 – 0.2 g/m3 at a gas flow rate of 0.06 m3/h corresponding to an empty bed residence time (EBRT) of 2.5 min for 38 days resulting in a steady state removal of 84%. The residual DCM concentration in liquid phase was 5ppm and dissolved oxygen level was 3-4 ppm. pH decreased from 7 to 4.5 in the media, which indicated biodegradation and formation of acidic metabolites. The performance of RBC was compared with that of a biofilter packed with a mixture of garden compost and ceramic beads. The biofilter was operated at an inlet concentration of 0.15 – 0.21 g/m3 and at a gas flow rate of 0.06 m3/h corresponding to an empty bed residence time (EBRT) of 1.47 min for 90 days to reach steady state removal efficiency of 88%. Thus RBC system seems to be a potentially alternative to biofilter

Using Social Media Monitoring Data to Forecast Online Word-of-Mouth Valence: A Network Autoregressive Approach

Managers increasingly use social media for marketing research, particularly to monitor what consumers think about brands. Although social media monitoring can provide rich insights into consumer attitudes, marketers typically use it in a backward-looking manner — that is, to measure past online word-of-mouth (WOM) valence (i.e., sentiment). This article proposes a novel method for using social media monitoring in a forward-looking manner to forecast brands’ future online WOM valence. The approach takes into account information on related brands based on the premise that consumers’ attitudes toward one brand are likely relative to — and therefore associated with — attitudes toward other brands. The method infers associative relations between brands from social media monitoring data by observing which brands are mentioned at the same time in the same social media sources, thus enabling construction of time-varying brand “networks” for representing interdependencies between brands. The authors test six possible methods for capturing brand interdependencies (Jaccard, Dice, anti-Dice, correlation, normalized correlation, and Euclidean distance) and examine the relative performance of each alternative method with a view to identifying the best approach

Reaction zones and their structure in MILD combustion

Three-dimensional direct numerical simulation (DNS) of turbulent combustion under moderate and intense low-oxygen dilution (MILD) conditions has been carried out inside a cuboid with inflow and outflow boundaries on the upstream and downstreamfaces respectively. The initial and inflowing mixture and turbulence fields are constructed carefully to be representative of MILD conditions involving partially mixed pockets of unburnt and burnt gases. The combustion kinetics is modelled using a skeletal mechanism for methane-air combustion, including non-unity Lewis numbers for species and temperature dependent transport properties. The DNS data is analysed to study theMILD reaction zone structure and its behaviour. The results show that the instantaneous reaction zones are convoluted and the degree of convolution increases with dilution and turbulence levels. Interactions of reaction zones occur frequently and are spread out in a large portion of the computational domain due to the mixture non-uniformity and high turbulence level. These interactions lead to local thickening of reaction zones yielding an appearance of distributed combustion despite the presence of local thin reaction zones. A canonical MILD flame element, called as MIFE, is proposed which represents the averaged mass fraction variation for major species reasonably well, although a fully representative canonical element needs to include the effect of reaction zone interactions and associated thickening effects on the mean reaction rate.YM acknowledges the financial support of Nippon Keidanren and Cambridge Overseas Trust. EPSRC support is acknowledged by NS. The support of Natural Sciences and Engineering Research Council of Canada is acknowledged by TL. This work made use of the facilities of HECToR, the UK’s national high-performance computing service, which is provided by UoE HPCx Ltd at the University of Edinburgh, Cray Inc and NAG Ltd, and funded by the Office of Science and Technology through EPSRCs High End Computing Programme.This is an Accepted Manuscript of an article published by Taylor & Francis in Combustion Science and Technology on 26 Jun 2014, available online: http://wwww.tandfonline.com/10.1080/00102202.2014.902814

Sedimentation of an ellipsoid inside an infinitely long tube at low and intermediate Reynolds numbers

The motion of a heavy rigid ellipsoidal particle settling in an infinitely long circular tube filled with an incompressible Newtonian fluid has been studied numerically for three categories of problems, namely, when both fluid and particle inertia are negligible, when fluid inertia is negligible but particle inertia is present, and when both fluid and particle inertia are present. The governing equations for both the fluid and the solid particle have been solved using an arbitrary Lagrangian-Eulerian based finite-element method. Under Stokes flow conditions, an ellipsoid without inertia is observed to follow a perfectly periodic orbit in which the particle rotates and moves from side to side in the tube as it settles. The amplitude and the period of this oscillatory motion depend on the initial orientation and the aspect ratio of the ellipsoid. An ellipsoid with inertia is found to follow initially a similar oscillatory motion with increasing amplitude. Its orientation tends towards a flatter configuration, and the rate of change of its orientation is found to be a function of the particle Stokes number which characterizes the particle inertia. The ellipsoid eventually collides with the tube wall, and settles into a different periodic orbit. For cases with non-zero Reynolds numbers, an ellipsoid is seen to attain a steady-state configuration wherein it falls vertically. The location and configuration of this steady equilibrium varies with the Reynolds number

Morphological and statistical features of reaction zones in MILD and premixed combustion

Direct numerical simulation (DNS) results of turbulent MILD premixed and conventional (undiluted) premixed combustion have been investigated to shed light on the physical aspects of reaction zones and their morphology inMILD combustion. Results of a premixed case are used for comparative analyses. The analyses show that the regions with strong chemical activity in MILD combustion are distributed over a substantial portion of the computational domain unlike in the premixed case where these regions are confined to a small portion of the domain. Also, interactions of reaction zones are observed in MILD combustion with their spatial extent increasing with dilution level. These interactions give an appearance of distributed combustion for MILD conditions. The morphology of these reaction zones is investigated using the Minkowski functionals and shapefinders commonly employed in cosmology. Predominant sheet-like structures are observed for the premixed combustion case whereas a pancake-like structure is observed as the most probable shape for the MILD cases. Spatial and statistical analyses of various fluxes involved in a progress variable transport equation are conducted to study autoignitive or propagative characteristics of MILD reaction zones. The results suggest that there are local regions with autoignition, propagating-flames, and their coexistence for the conditions considered in this study. Typically, reaction dominated or ignition front and propagating-flame dominated regions are entangled for high dilution cases. Scalar gradient plays a strong role on whether reaction or propagating-flame dominated activities are favoured locally.YM acknowledges the financial support of Nippon Keidanren and Cambridge Overseas Trust. EPSRC support is acknowledged by NS. This work made use of the facilities of HECToR, the UK’s national high-performance computing service, which is provided by UoE HPCx Ltd at the University of Edinburgh, Cray Inc and NAG Ltd, and funded by the Office of Science and Technology through EPSRCs High End Computing Programme.This is the accepted manuscript. The final version is available from Elsevier at http://www.sciencedirect.com/science/article/pii/S001021801400128X

Simulation of premixed combustion with varying equivalence ratio in gas turbine combustor

RANS simulation of a gas turbine combustor with complex geometry is performed. The turbulence is modelled using a two-equation approach. The scalar mixing and combustion is modelled using a flamelet based approach for partially premixed combustion. In this approach transport equations to described scalar mixing and reacting fields and their statistical interactions are solved along with standard conservation equations. The boundary conditions are specified using measured values. The computed spatial variations of averaged temperature and dry mole fractions of various scalars, including CO and NOx, compared quite well with measured values. The results of this combustion model are compared to the eddy-dissipation-concept (EDC) model commonly used for gas turbine combustion calculation and this comparison showed that the results of partially premixed combustion model is improved considerably.This is the author accepted manuscript. The final version is available from the American Institute of Aeronautics and Astronautics via http://dx.doi.org/10.2514/1.B3551