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The demand on sago starch in industrial application is continuously growing, but the research on its drying behavior is still limited. In this study, ten thin layer drying models were compared through four drying temperatures in order to find the best model to describe the drying characteristic of sago starch. According to the results, sago starch exhibits drying during the falling rate period. The moisture diffusivities ranged from 8.56 × 10−10 to 1.39 × 10−9 m2/s that varied through drying temperature while the activation energy was 16.18 kJ/mol. Based on the study, the drying pattern was best described by the Page model.

Hydrodynamic instabilities are regarded as important but are undesirable occurrences for the systems used in process industries, which involve steam. These instabilities affect to a great extent the life line of the safe operation of their systems by inducing thermal stresses and steam induced water hammers. On the basis of system operational analysis, it was found that condensation induced hydrodynamic instabilities were responsible for one third of the destructive events in steam driven systems and their attributes in power and process industry. Thus it becomes vital to investigate the influence of critical parameter such as sub-cooling to curb the destructive effects due to hydrodynamic instabilities on to the process equipment. Here for steam water two phase flows, the attenuation of hydrodynamic instabilities due to sub-cooling and inlet pressure has been investigated. It was found that sub-cooling has more pronounced and notable effect on the attenuation of these instabilities.

The phenomenon of direct-contact condensation gains attention because of various industrial applications; nuclear reactor emergency core cooling systems,steam driven jet injectors, direct-contact heat exchangers etc..The phenomenon was investigated computationally by injecting an inclined steam jet using a supersonic nozzle submerged in subcooled water. The condensation mechanism is based on two resistance model, which involves consideration of the heat transfer process on both sides of the interface along with use of a variable steam bubble diameter. For computations, ANSYS Fluent based Euler-Euler multiphase model is used. The angle of inclination varies from 5oto 45oat constant inlet pressure of 7 bars with water temperature of 30°C. The maximum penetration length is achieved using a right angled vertical injection.

Overhead high voltage transmission conductors used worldwide are produced in several configurations. A multi-strand conductor of the type ACSR330 is typically used for 275 kV overhead transmission lines. The conductor is composed of 7 inner strands of Ultra High Strength Galvanized Steel for the mechanical support of the conductor and 26 strands of high conductivity Aluminum wires meant for power transfer over long distances. During the use, weather conditions and power fluctuations tend to degrade the properties of these conductors. In the present work, study of the state of galvanization and oxidation of an ACSR330 conductor is undertaken with a view to understand the effectiveness of the loss in corrosion protection and changes in the zinc coating on the galvanized steel strands after use for 25 to 30 years. The Scanning Electron Microscopy (SEM), X Ray Diffraction (XRD) and Energy Dispersive Analysis through X rays (EDAX) provide a very useful insight into the state of the conductor and gives important information to the strategic decision maker, whether or not to replace the conductor. It was observed in the present study that the zinc coating diffuses inside the steel strand under temperature and time effect. This unique study on the used conductors also reveals that the morphology of the coating and its interface structure changes significantly compared to an unused conductor of the same age.