Demand for improvement in shipbuilding is increasing and due to this many manufacturing industries are developed rapidly and come up with very advanced designs and development in this field. Specifically, there is a good scope for improvements in the structure of the Class 6 catamaran hull spine beam. Usually, the multihull catamaran operates beyond its design specifications and due to unforeseen winds, waves, and deteriorating weather, the hull spine beam faces more impacts what leads to failure and weakening after decades of sustained operation. The analysis results obtained in this paper show great improvement in the design of the catamaran hull spine beam, which would give an idea of overall improvement in catamaran design and its performance. The design methods for developing catamaran and bulkheads are considered in the study. The whole analysis is performed on ANSYS software by following step by step simulation procedure using the FEM methodology. At first, simulation of simple the 3D model without considering bulkheads is done and results are observed. In the next steps, bulkheads are added to the spine beam at equal distance in a sequence of 1,3,5,7, and 9 along the beam. The obtained results confirm that adding more and more bulkheads makes the structure bulky, but adding it up to a certain level helps reduce maximum Von-Mises stress by 75.9% and total deformation of the spine beam by 70.9%, which makes the structure more rigid and essentially improves the strength of the catamaran hull spine beam.

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In this work resource saving technique is used for shape optimization of 3D mechanical objects. According to statistical data, appearance of cracks in the areas of barrel support pads of tank wagons often causes damages to the barrels. The shape optimization of barrel support pads of a tank wagon is implemented and, as result, the concentration of stresses is significantly reduced in the barrel support areas. The optimization technique is based on CAD/CAE, design of experiment, approximation and optimization software packages. The shape of the support pads is defined by NURBS polygon points that serve as design parameters. For reduction of computational resources, FE models of tank wagon are replaced with high-quality metamodels which are based on locally weighted polynomials. The specific recommendations for the shape of the pads are given. As the second object truly spatial tetrapod is considered. The optimal curved shape of the tetrapod for lattice structure is elaborated.

People's thermoregulation may be hampered by exposure to extreme temperatures. Because of this, it is crucial to consider how fabric cooling and ventilation may affect human comfort while designing clothing. There is a demand on the market for more effective technical solutions and materials to be used in the external part of protective gear, while also ensuring the necessary ventilation even in warm environmental conditions and during heavy physical load. This is due to the growing interest in the market for efficient protection of the human body against exposure to extreme weather conditions. In this article simple elliptical model of the body and the jacket is used to reduce the complexity of the problem. Five different shapes of ventilation elements named as E1 to E5 are designed for the study and the numerical results for the pressure, temperature and heat flux are calculated using SolidWorks Flow Simulation at three different inlet air velocity of 2, 5 and 8 m/s. The acquired results display interesting flow patterns and how the ventilation elements' shapes might influence the flow at various wind velocities. The results are compared and analyzed in terms of heat flux, pressure difference and temperature difference. The main objective is to determine which element's geometrical shape gives the smallest flow energy losses in the cell flow channel. If the pressure difference is higher, flow energy losses will also be high, and if the flow energy losses are higher, the body cooling decreases. The obtained results show that pressure difference increases gradually with the increasing inlet velocity. Moreover, results also indicates how different shapes of ventilation elements can affect the flow, pressure difference and flow energy losses. Based on analysis of obtained simulation results the most perspective ventilation element is proposed.