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This study investigates the kinetic modeling of CH4/H2/Air mixture with nanosecond pulse discharge (NSPD) by varying H2/CH4 ratios from 0 to 20% at ambient pressure and temperature. A validated version of the plasma and chemical kinetic mechanisms was used. Two numerical tools, ZDPlasKin and CHEMKIN, were combined to analyze the thermal and kinetic effects of NSPD on flame speed enhancement. The addition of H2 and plasma excitation increased flame speed. The highest improvement (35%) was seen with 20% H2 and 1.2 mJ plasma energy input at ϕ = 1. Without plasma discharge, a 20% H2 blend only improved flame speed by 14% compared to 100% CH4. The study found that lean conditions at low flame temperature resulted in significant improvement in flame speed. With 20% H2 and NSPD, flame speed reached 37 cm/s at flame temperature of 2040 K at ϕ = 0.8. Similar results were observed with 0% and 5% H2 and a flame temperature of 2200 K at ϕ = 1. Lowering the flame temperature reduced NOx emissions. Combining 20% H2 and NSPD also increased the flammability limit to ϕ = 0.35 at a flame temperature of 1350 K, allowing for self-sustained combustion even at low temperatures.

Tensegrity structures which are comprised of bars and strings are very lightweight structures and they have the capability to deform and remain stable. For these properties they have been utilized in various fields of engineering for various purposes. One of the potential application of tensegrities is in the area of robotics. Three bar tensegrity is a basic unit structure, the dynamics of which can be utilized for tensegrity based robots. Due to its similar geometrical shape and easy control of strings, and by the application of inward compressive load, the movement of whole robot can be controlled. In this paper, the dynamics of three bar tensegrity structure has been studied under compressive load. The mathematical model for the structure has been built; and node matrix and connectivity matrix have been defined to describe the structure. The simulation has been performed on ADAMS software to analyze the movements of bar and deformation in strings under the effect of compressive load. All the strings have been grouped according to the similar deformation experienced by them. In addition to that, compression and twisting of top layer of the structure has been investigated. The obtained results provide the base for the construction of extremely lightweight robotic structure

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