Modelling of baffles in electostatic precipitator (ESP0 to achieve optimum flow distribution

Papers presented to the 11th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, South Africa, 20-23 July 2015.Electrostatic Precipitators (ESP) are the most reliable emission control devices that are used in coal fired power plants to capture fine particles for reducing exhaust emission. Its efficiency is more than 99% or more. However, capturing submicron particles are still a problem due to complex flow distributions and design limitations of ESP. In this study, two different shapes of baffles inside the ESP have been considered to assess their influence on the flow pattern using computational fluid dynamics (CFD) code ‘ANSYS FLUENT’.. Due to different shapes, the flow distribution will be changed inside the ESP which is expected to affect and increase the residence time of flue gas. The results of this paper indicate that the proposed shapes can influence in collecting more fine particles.am201

Forced convection heat transfer performance of porous twisted tape insert

Heat transfer performance of porous twisted tape insert in a circular tube was experimentally investigated. Tube wall temperatures and pressure drops along the axial distance of the test section at steady state condition were measured for different flows having Reynolds number ranging from 1.4 x 104 to 5.2 x 104 for both the plain and the tube with porous twisted tape insert. Heat transfer coefficient, friction factor, and pumping power were calculated from the measured data. Heat transfer and fluid flow characteristics of the porous twisted tape inserted tube were explained from the measured and calculated values. Performance of the porous twisted tape inserted tube was also evaluated. The results showed for porous twisted tape inserted tube, the average heat transfer coefficient was 2.60 times higher, the heat flux was 1.55 times higher, the friction factor was 2.25 times higher and the pumping power was 2.0 times higher than those of plain tube values for similar flow conditions

Maximizing energy density of lithium-ion batteries for electric vehicles: A critical review

Currently, lithium-ion batteries (LIBs) have emerged as exceptional rechargeable energy storage solutions that are witnessing a swift increase in their range of uses because of characteristics such as remarkable energy density, significant power density, extended lifespan, and the absence of memory effects. Keeping with the pace of rapid development, specific purpose-oriented features of LIBs are being searched for to satisfy certain requirements. In the case of Electric Vehicles (EVs), the expected growth of LIB use is hindered because of the present level of driving range and battery pack size. However, both issues can be improved with elevated energy density at the cell level. Because high energy density will not only increase the driving range but also reduce the number of cells that will be required to deliver the same amount of power, thereby reducing the battery pack size. Higher energy density is achievable by designing LIB cells through materials-oriented design as well as cell parameter-focused design. Herein, a brief critical overview of LIB cell configuration for maximizing energy density of LIBs for EVs is presented considering viewpoints related to both material-oriented and cell parameter-focused optimization approaches

Washing Durability of PDMS-Conductive Fabric Composite Realizing Washable UHF RFID Tags

International audienceIn this letter, we present experimental investigations on washing durability of a polydimethylsiloxane (PDMS)-conductive fabric composite to validate its applicability for the realization of flexible wearable antennas that can withstand multiple washing cycles. For this purpose, we designed an ultrahigh-frequency (UHF) radio frequency identification (RFID) passive tag antenna and fabricated several prototypes using such materials combination. Understanding the challenge of having a robust integration of a lumped electronic component (e.g., RFID IC) on a flexible antenna, a new way to improve the interconnection has also been investigated. The tag prototypes were subjected to recurrent machine-washing tests, and after each washing cycle, their performance was analyzed mainly in terms of the read range. The results reveal that, with a proper treatment on the antenna-IC fixture interconnection, the tag antennas developed with the PDMS-conductive fabric composite can maintain their performance very well, showing a minimum degradation in the read range after 15 cycles of washing. © 2002-2011 IEEE

Performance assessment in a heat exchanger tube fitted with double counter twisted tape inserts

The present study explored the effects of the double counter twisted tapes on heat transfer and fluid friction characteristics in a heat exchanger tube. The double counter twisted tapes were used as counter-swirl flow generators in the test section. The experiments were performed with double counter twisted tapes of four different twist ratios (y = 1.95, 3.85, 5.92 and 7.75) using air as the testing fluid in a circular tube turbulent flow regime where the Reynolds number was varied from 6950 to 50,050. The experimental results demonstrated that the Nusselt number, friction factor and thermal enhancement efficiency were increased with decreasing twist ratio. The results also revealed that the heat transfer rate in the tube fitted with double counter twisted tape was significantly increased with corresponding increase in pressure drop. In the range of the present work, heat transfer rate and friction factor were obtained to be around 60 to 240% and 91 to 286% higher than those of the plain tube values, respectively. The maximum thermal enhancement efficiency of 1.34 was achieved by the use of double counter twisted tapes at constant blower power. In addition, the empirical correlations for the Nusselt number, friction factor and thermal enhancement efficiency were also developed, based on the experimental data

Rhinacanthin C ameliorates hyperglycaemia, hyperlipidemia and pancreatic destruction in streptozotocin–nicotinamide induced adult male diabetic rats

Effect of Rhinacanthin C on hyperglycaemia, hyperlipidemia and pancreatic dysfunction in diabetes was investigated. In-vitro effect of Rhinacanthin C on glucose uptake was studied in 3T3-L1 cell line. Meanwhile, in-vivo effect of 28-days treatment with 5 mg/kg/day or 20 mg/kg/day Rhinacanthin C was studied in streptozotocin–nicotinamide induced male diabetic rats. Following completion of treatment, fasting blood glucose (FBG), HbA1c, insulin and lipid profile levels were measured by biochemical assays. Histopathological changes in pancreas were observed by light microscopy while levels of pancreatic oxidative stress were determined by enzymatic assays. Expression of insulin, TNFα, Ikkβ and caspase-3 in pancreas were quantified by immunohistochemistry. Molecular docking was used to identify interactions between Rhinacathin C with SOD or GPx enzymes. Dose-dependent increase in glucose uptake was observed with increasing doses of Rhinacathin C. Plasma FBG, HbA1c and lipid profile except LDL levels and pancreatic malonaldehyde level were reduced but serum insulin and pancreatic anti-oxidative enzymes (SOD, CAT and GPx) levels were increased in diabetic rats receiving Rhinacanthin C treatment. Decreased pancreatic histopathological changes with higher pancreatic insulin and Glut-2 levels but lower TNFα, Ikkβ and caspase-3 levels were observed in diabetic rats receiving Rhinacanthin C (P<0.05 compared to non-treated diabetic rats). In diabetic rats which received Rhinacathin C, changes in the above parameters did not achieve the value in non-diabetic rats. Docking shows Rhinacathin C possesses high degree interactions with SOD and GPx. By possessing these effects, Rhinacanthin C could be used as agent to alleviate pancreatic and other complications in diabetes

Heat transfer and pressure drop characteristics in turbulent flow through a tube

An experimental investigation has been carried out for turbulent flow through a tube with perforated strip inserts. Strips were of mild steels with circular holes of different diameters. Flow varies, with ranging Reynolds numbers from 15,000 to 47,000. Air velocity, tube wall temperatures, and pressure drops were measured for a plain and strip-inserted tube. The heat transfer coefficient and friction factor were found to be 2.80 times and 1.8 times, respectively, that of the plain tube. The heat transfer performance was evaluated and found to be 2.3 times that of the plain tube based on constant blower power