Vacuum assisted resin infusion (VARI) is a process applied to manufacture large structures of composite materials, such as aircraft wing and fuselage skins, but the process parameters are designed by experience or lots of experiments. In this paper, the filling process of VARI for composite fuselage skin was analyzed based on simulation and optimized location of resin inlet ports. Firstly, we made 3D model of fuselage skin and simulated impregnation process. Secondly, we determined the location and quantity of resin inlet ports based on simulation results. The simulations showed that it is advisable to reduce the filing time not only by adding the resin inlet quantity, but also choosing optimal locations.

Aircraft total weight plays a major role in aircraft design which results in additional payloads and better performance. There are many ways to reduce weight of aircraft structures, for example, using composite materials.Composite materials such as CFRP offer significant weight reduction for aircraft. Weight reduction improves fuel efficiency of the aircraft which results cost of savings. Besides using these light materials structural design optimization is currently a valid methodology which is applied in advanced engineering. Topology optimization is used to yield an optimized shape and material distribution for a set of loads and constraints within a given design space. Whereas this paper deals with topology optimization of fuselage ribs. By using this optimization technique, weight can be reduced 18.36 % of the original weight.

The problem of the selecting the optimal lay-up stacking of polymer composite materials for the load-bearing elements of the rear part of fuselage structure is considered. The comparison of two approaches to the design of the load-bearing elements is carried out. The first of them is the use of multilayered composite material for the load-bearing elements, the stacking angles of which is selected from a given discrete set, and the second is the use of composite material with a continuous range of variables in fabric lay-up angles. As a result design optimization, it is shown that using an optimization method with a continuous range of lay-angles allows reducing the weight of the load-bearing elements by 12.79%

The paper presents a comparative analysis of methods and results of calculating the physical and mechanical characteristics of single-layered and multi-layered polymer composite materials (PCM). The object of the study is a polymer composite which consists of epoxy binder and carbon fiber reinforcements. The principle of multiscale modelling is applied to determine the physical and mechanical characteristics of the composite. Within the framework of this study, a representative volume element (RVE), the structure of which corresponds the characteristics of real materials, is used. The initial data for the calculation in this case are physical and mechanical characteristics of anisotropic fibers (carbon fabric) and an isotropic binder, as well as the geometric model of the RVE. As a result of the calculation, the effective characteristics of a quasi-homogeneous anisotropic material suitable for numerical analysis of the composite structures are determined. A comparison of the results of determining the physical and mechanical characteristics of the polymer composite using ANSYS Material Designer and MSC Digimat software packages for various size of RVE model is carried out and ANSYS Workbench software is also used to perform the stress-strain conditions of RVE model to determine the physico-mechanical characteristics of polymer composites.

No abstract