M. Rajendrakumar

Bio: M. Rajendrakumar is an academic researcher. The author has contributed to research in topics: Thermal hydraulics & Nuclear engineering. The author has an hindex of 1, co-authored 1 publications receiving 127 citations.

Design optimization of flow distribution device in bottom header of ihx for future indian fbr

Abstract: The next generation commercial fast breeder reactors in India are in design phase. Design optimization of nuclear components is important task with respect to its safe operation and economy consideration. Intermediate heat exchanger (IHX) is a typical shell and tube type heat exchanger, in which primary sodium in shell side exchanges heat with secondary sodium in the tube side. Primary sodium flows shell side from top to bottom through inlet and outlet window. Secondary sodium enters the IHX through central tube and flows downward into the bottom header before it enters ~3900 tubes. Secondary sodium flows upward through tubes and extract heat from primary sodium. Primary sodium flows as crossflow near inlet and outlet windows and axial in remaining length of tubes. Peripheral tubes extract higher heat compared to inner rows. Therefore, it is recommended to allow 30% higher flow of secondary sodium in 7 outer peripheral rows of tubes to achieve a nearly uniform secondary sodium outlet temperature. Towards this a simplified design of flow distribution device was conceptualized. The main purpose of this device is to divert the flow to outer rows of tube. With the present motivation, a three-dimensional CFD study of the bottom header of IHX of FBRs have been carried out to explore the ways to simplify the design of FDD. Parametric studies have been carried out to achieve the desired flow distribution. The effect of conical diffuser and vertical baffle inside bottom header of IHX is quantified.

Thermal properties of treated sugar palm yarn/glass fiber reinforced unsaturated polyester hybrid composites

Abstract: In this work, the effects of alkaline treatment and hybridization on the thermal properties of sugar palm yarn/glass fiber were investigated. The sugar palm fiber was treated with 1% of sodium hydroxide (NaOH) solution for 1 h and the ratio of between matrix and reinforcement was 70/30 wt.% and 60/40 wt.%, respectively, while the ratio of reinforcement between sugar palm yarn fiber and glass fiber was 70/30 wt.%, 60/40 wt.% and 50/50 wt.%, respectively. The thermal properties of the hybrid composites were analyzed using a dynamic mechanical analyzer (DMA) and Thermogravimetric analysis (TGA). The storage modulus (E'), loss modulus (E") and damping factor (tan δ) were evaluated as a function of the alkaline treatment and different percentages of fiber loading. Also, the peak high was investigated for the tan δ curves. In the glassy state area, a higher glass fiber loading hybridized with treated sugar palm fiber exhibited the highest storage modulus, loss modulus and the lowest damping factor. TGA demonstrated that the percentage of residue decreased as the glass fiber loading increased. Overall, the hybridization of glass fiber with treated sugar palm fiber enhances the thermal properties of the hybrid composites for structural applications.

Thermo-mechanical performances of polypropylene biocomposites based on untreated, treated and compatibilized spent coffee grounds

Abstract: In this work, biocomposites were produced by compounding polypropylene (PP) with spent coffee grounds (SCG) obtained after soluble coffee preparation. The samples were prepared by extrusion compounding and injection molding using different SCG contents (0, 5, 10, 15 and 20wt.) in order to investigate the effect of particle loading on the thermal, rheological and mechanical properties. Then, the effect of bleaching treatments and the use of compatibilizers (silane and styrene-ethylene-butene-styrene-graft-maleic anhydride) on the biocomposites properties at 15 wt% was examined. The results showed that good SCG dispersion and distribution into PP was achieved and that bleaching led to better interfacial interaction, which was further increased by using a coupling agent. As a result, the tensile and torsion properties were increased.