Aluminium metal matrix composite is one of the most promising engineering material and gradually emerging technology in automobile industries. There are usage of this composite material in certain critical applications like clutch pressure and face plate assembly due to their enhanced mechanical, wear and physical properties. In the present study, A356 aluminum alloy reinforced with SiC and Al 2 O 3 particle was made by stir casting process. The effects of different volume fractions of SiC and Al 2 O 3 particle reinforcement on microstructure and mechanical properties have been investigated. The tensile, yield strength and hardness have been increased in the particulate containing composites. As compared to base alloy, 20 % volume fraction of SiC reinforced composites showed 16 % increase in tensile strength and 10 % volume fraction of Al 2 O 3 reinforced composites showed 19 % increase in tensile strength. The yield strength of 20 % SiC and 10 % Al 2 O 3 containing samples nearly 50 % higher than those of the base alloy. Dislocation density, precipitation hardening and changes in grain size are the main mechanisms enhancing the mechanical properties of particulate reinforced composites. The 20 % SiC and 10 % Al 2 O 3 reinforced composites have been identified as optimized composites for clutch pressure/face plate application.

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This investigation reports the experimental and theoretical results carried out to evaluate the gas holdup for air-water system in a novel hybrid rotating and reciprocating perforated plate bubble column under countercurrent condition. The response of this hybrid column is found to be similar to that of reciprocating plate column (RPC) showing mixer-settler, transition, and emulsion regions. The effect of agitation level, superficial gas velocity, superficial liquid velocity, perforation diameter, and plate spacing on gas holdup is studied and found to be significant. The gas holdup is found to be least in the range of agitation level of 1.3-1.5 cm/s. For all the superficial gas and liquid velocities considered in this present investigation, the critical agitation level at minimum gas holdup remains nearly same. The gas holdup in this hybrid column is 1.2-1.7 times higher in mixer-settler region and 2.1-2.7 times higher in emulsion region than that of RPC. Correlations have been developed and found to concur with the experimental values. It can be used with 95% accuracy.

This investigation reports the experimental and theoretical results carried out to evaluate the axial dispersion number for an air-water system in a novel hybrid rotating and reciprocating perforated plate bubble column for single phase and two phase flow conditions. Axial dispersion studies are carried out using stimulus response technique. Sodium hydroxide solution is used as the tracer. Effects of superficial liquid velocity, agitation level and superficial gas velocity on axial dispersion number were analyzed and found to be significant. For the single phase (water) flow condition, it is found that the main variables affecting the axial dispersion number are the agitation level and superficial liquid velocity. When compared to the agitation level, the effect of superficial liquid velocity on axial dispersion number is more predominant. The increase in superficial liquid velocity decreases the axial dispersion number. The same trend is shown by agitation level but the effect is less. The rotational movement of the perforated plates enhances the radial mixing in the section; hence, axial dispersion number is reduced. For the two phase flow condition, the increase in superficial liquid velocity decreases the axial dispersion number, as reported in the single phase flow condition. The increase in agitation level decreases the axial dispersion number, but this decreasing trend is non-linear. An increase in superficial gas velocity increases the axial dispersion number. Correlations have been developed for axial dispersion number for single phase and two phase flow conditions. The correlation values are found to concur with the experimental values.