Improving rollover and stability of the vehicles is the indispensable part of automotive research to prevent vehicle rollover and crashes. The main objective of this work is to develop active control mechanism based on fuzzy logic controller (FLC) and linear quadratic regulator (LQR) for improving vehicle path following, roll and handling performances simultaneously. 3-DOF vehicle model including yaw rate, lateral velocity (lateral dynamic) and roll angle (roll dynamic) were developed. The controller produces optimal moment to increase stability and roll margin of vehicle by receiving the steering angle as an input and vehicle variables as a feedback signal. The effectiveness of proposed controller and vehicle model were evaluated during fishhook and single lane-change maneuvers. Simulation results demonstrate that in both cases (FLC and LQR controllers) by reducing roll angle, lateral acceleration and side slip angles remain under 0.6g and 4° during maneuver, which ensures vehicle stability and handling properties. Finally, the sensitivity and robustness analysis of developed controller for varying longitudinal speeds were investigated.

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Numerical investigation of the effects of magnetic field strength, thermal radiation, Joule heating, and viscous heating on a forced convective flow of a non-Newtonian, incompressible power law fluid in an axisymmetric stretching sheet with variable temperature wall is accomplished. The power law shear thinning viscosity-shear rate model for the anisotropic solutions and the Rosseland approximation for the thermal radiation through a highly absorbing medium are considered. The temperature dependent heat sources, Joule heating, and viscous heating are considered as the source terms in the energy balance. The non-dimensional boundary layer equations are solved numerically in terms of similarity variable. A parameter study on the Nusselt number, viscous components of entropy generation, and thermal components of entropy generation in fluid is performed as a function of thermal radiation parameter (0 to 2), Brinkman number (0 to 10), Prandtl number (0 to 10), Hartmann number (0 to 1), power law index (0 to 1), and heat source coefficient (0 to 0.1).

Thermal radiant heating through distinct heat sources is of interest for the thermal loading of thin objects as it is used in residential applications, furnaces, and insulator designs. In this paper, an optimal design for a thermal radiant system by discrete suspended heat sources is analyzed in a side open cavity used for heating the top plate, while the bottom plate is kept at a constant temperature, using the entropy generation minimization method. To avoid pressure fluctuations, the semi-implicit method for pressure linked equations method is used, which solves the continuity, Navier-Stokes, fluid energy, and surface energy equations simultaneously. The system is optimized based on the characteristic length of discrete heat sources, height of discrete heat sources from the bottom plate, the distance between discrete heat sources, the number of discrete heat sources, and the aspect ratio of the cavity that finds the optimal location of heating elements. In addition to the geometrical parameters, the effects of the thermal loading parameters on the optimal position are investigated.