In the present work, numerical analyses of air flow in HVAC duct have been carried out for enhancement of cooling/heating performance. For the analyses, three-dimensional Reynolds-averaged Navier-Stokes equations have been solved with the shear stress transport turbulence model. The numerical results were validated in comparison with the experimental data. Based on the numerical results, the HVAC duct was designed to reduce the pressure loss. The modified duct geometry shows largely reduced pressure drop in comparison with the reference geometry. And, through modified duct shape, the performance of air conditioning has been enhanced.

Parametric study on an outlet plenum of a PBMR type gas cooled nuclear reactor has been carried out using three-dimensional Reynolds-Averaged Navier-Stokes equations. Shear stress transport turbulence model is used for analysis of turbulence. Two geometric parameters are selected, namely, displacement on the horizontal line and angle of rotation about the center of gravity of the roof support block. Pressure drop and uniformity of flow distribution in the outlet plenum have been considered as the performance parameters of an outlet plenum of the PBMR. The results show that the performance parameters are affected considerably by the location of the roof support block.

Steel slag has the nature to hydrate and expand when in contact with non-reacting CaO and water, and thus can be used only in limited scope for landfill disposal as well as for recycling as civil construction aggregates. In order to use such steel slags more efficiently, the applicability of steel slag as sand mat alternative material was reviewed. In general, sand mat is used in soft ground surface reinforcement method and horizontal drain method, and is installed simultaneously with soft ground vertical drain method. Therefore in this study steel slag designing method and application standard etc were examined to recycle steel slag as sand mat alternative material, and laboratory soil test and model test were done. Test results indicated that the designing method and application standard meet various environment and quality standards, meaning that steel slag can be utilized as sand mat alternative material, and analysis of slag mat bearing capacity also indicated that use of steel slag produces double or more bearing capacity compared with existing sand mat.

No abstract