Anil Kumar Tiwari

Shape Factor for Steady State Heat Transfer between Swimming Pool Waterand Surrounding Ground

A simple, efficient, and abundantly available agricultural waste material, banana pseudo-stem (BPS) was examined as raw material for the extraction of potassium. The effects of various process parameters such as temperature, initial pH, contact time, banana pseudo-stem dosage and size of banana pseudo-stem particles on potassium extraction efficiency were studied by running batch experiments in Erlenmeyer flasks. Response Surface Methodology (RSM) was used to design the experimental runs. Modelling and optimization of process variables to obtain maximum extraction of potassium from raw material were done using RSM.The maximum extraction efficiency of potassium was found to be 83.96% at a temperature of 400C, pH of 1, contact time of 30 min, BPS weight of 26.076 g and initial BPS size of 300. The results revealed that banana pseudo-stem can be used as good source for potassium extraction.

Performance of Functionally Graded Exponential Annular Fins of Constant Weight

The present work aims at investigating the performance of exponential annular fins of constant weight made of functionally graded materials (FGM). The work involves com‐ putation of efficiency and effectiveness of such fins and compares the fin performances for different exponential profiles and grading parameters, keeping the weight of the fin constant. The functional grading of thermal conductivity is assumed to be a power func‐ tion of radial co-ordinate which consists of parameters, namely grading parameters, vary‐ ing which different grading combinations can be investigated. Fin material density is assumed to be constant and temperature gradient exists only along the radial direction. The convective coefficient between the fin surface and the environment is also assumed to be constant. A general second-order governing differential equation has been derived for all the profiles and material grading. The efficiency and effectiveness of the annular fin of different geometry and grading combinations have been calculated and plotted and the results reveal the dependence of thermal behavior on geometry and grading parame‐ ter. The effect of variation of grading parameters on fin efficiency and effectiveness is re‐ ported. The results are provided in the form of 2-D graphs, which can be used as design monograms for further use.