This paper presents a methodology to identify the different grain types from image samples of tray containing multiple grains using colour and textural features. The multiple grain images are segmented into individual grain images. From these images, eighteen colour and twenty-four textural features are obtained. A neural network model is implemented for identification of bulk food grains. Five different types of grains namely, alasandi, green gram, metagi, red gram and wheat commonly used in Indian food preparations are considered in this work. The maximum and minimum food grain identification accuracies observed in this work are 94% and 80% for wheat and alasandi, respectively. The work finds application in development of machine vision system for grain identification, classification and grading.

Preliminary analysis for the S-CO2 Brayton power cycle development suggests small size and high operating speed of turbomachinery. The axial thrust due to the pressure differential generated in the turbomachinery is transferred to the bearing through the shaft. Angular contact ceramic bearings used for high speed operations are incapable of withstanding high axial loads. The current paper presents, theoretical and computational analysis of a 4-hole aerostatic thrust bearing for S-CO2 turbomachinery applications. CFD analysis is performed for different axial clearance gap between stationary and rotating discs of the thrust bearing. The computations have been performed for two different fluids — air and CO2. This computational domain of the flow regime splits into two regions: adiabatic flow through the orifice and isothermal flow in the clearance volume comprising the clearance gap. The influence of the following parameters such as, pressure distribution across thrust pad area, mass flow rate, load capacity and the local velocity in the gap on the stiffness of the bearing are investigated.

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This paper presents the coupled thermal and structural analysis of the rotating components of the generator using ABAQUS finite element solver. The interference between shaft and rotor is optimized to have a positive contact pressure and also minimize the stresses in the laminate at all operating speeds. Thermal analysis is performed to simulate the temperature distribution arising from the heat losses of generator. The flow path of the coolant is designed through the shaft to minimise the temperature rise of the generator. The resulting changes in the contact pressure between laminated disc and shaft is computed using sequentially coupled thermal and structural analysis. The thermal stresses of rotor are computed estimated and the design is optimized for transmitting torque at different operating speeds.

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