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This study aims to present the comparison between 2 different nickel-based superalloy materials, rene 41 and waspaloy through their application in designing a high-pressure (HP) turbine blade for a turboshaft engine. NACA 4-digit airfoil profile has been used to create the airfoil for the HP turbine blade. MATLAB software is used to create a graphical user interface for the selection of various parameters used to define the airfoil profile including the NACA airfoil number, angle of attack, number of grid points, grid type, trailing edge type, chord length, and the plot style. For this study, NACA 9618 airfoil is used to model a single HP turbine blade. Numerical flow analysis using vortex panel method (VPM) is carried out on the airfoil to obtain the flow characteristics. Further, several types of failure methodologies occurring in the turbine blades and standard industrial methods used to reduce failure cycles are discussed. Comparisons are carried out showing precipitation-hardened rene 41 exhibiting relatively larger Von-Mises stress values in comparison with age-hardened waspaloy at elevated temperature for thermo-mechanical loading in the blade structure. Steady-state simulation at 39,000 rpm yields maximum temperature values of 1056 °C and 1220 °C for rene 41 and waspaloy respectively, also yielding relatively close values for critical displacement at the shroud section of the blade. Analysis models are proposed to determine the effect of mechanical and thermal loads on the high-pressure turbine blade design.

An automatic protection guard for bikes reduces the impact to the side panels, engine, and the rider's leg when the bike collides with the ground, which follows the reverse quick return mechanism. Include a tilt sensor to monitor the bike's lean angle to activate the system and a wave spring inside the hollow bars to absorb the impact. A tilt sensor will be installed and will set a lean angle to the system. When the bike crosses the calibrated lean angle, the system activates and releases the bars from the system installed onto the bike frame and will take the first contact with the ground surface. To match real-life situations, the time taken for the protection guards to move from initial position to extreme position has been calculated using solid Works motion analysis with an average time taken is 0.14 s, and to find the total deformation different loads and different spring constants have been applied using Ansys software the average deformation is 12 mm. The system helps the rider to ride the bike in a safe mode. The total design system is dynamic and varies with the bike segment but follows the same mechanism.

In this paper, we talk about the use of Auxetics in Sports Helmets, orientation, and the type of auxetic used. It also covers how the newly designed auxetic structures can sustain more impact energy when compared to the existing auxetic structures. This comparison gives us more clarity about the uses of auxetics in various other applications. Auxetics in simple terms are structures that have a negative Poisson's ratio. This is just a structural property and does not depend upon the material. Hence, it can be used in so many different applications such as defense applications, sports applications, impact absorption, drug dispensers when pores are open, test bay containment, etc. On moving forward, modifying a structure showed that there are improvements concerning Poisson's ratio as well as impact resistance. The challenge was then to make the foam such that it can absorb maximum impact energy. Based on this hypothesis, the proposed design was tested against an existing structure to postulate the difference in the impact energy. The Poisson’s ratio obtained was a staggering improvement from −0.73 to −1.27 which shows 75% decrease in Poisson’s ratio while boasting an increase in the overall energy of 330% from 50 J to 165 J.