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In this study, the aeroelastic stability and response of an aircraft swept composite wing in subsonic compressible flow are investigated. The composite wing was modeled as an anisotropic thin-walled composite beam with the circumferentially asymmetric stiffness structural configuration to establish proper coupling between bending and torsion. Also, the structural model consists of a number of nonclassical effects, such as transverse shear, material anisotropy, warping inhibition, nonuniform torsional model, and rotary inertia. The finite state form of the unsteady aerodynamic loads have been modeled based on the indicial aerodynamic theory and strip theory in the subsonic compressible flow. Novel Mach dependent exponential approximations of the indicial aerodynamic functions have been developed. The extended Galerkin’s method was used to construct the mass, stiffness, and damping matrices of the nonconservative aeroelastic system. Eigen analysis of the system was performed to obtain the aeroelastic instability (divergence and flutter) boundaries. Also, solving the equations of motion in the time domain leads to the aeroelastic response of wing in different flight speeds. The obtained results are compared with the available results in the literature, which reveals an excellent agreement. The numerical results obtained in this article seek to clarify the effects of geometrical and material couplings and flight Mach number on the aeroelastic instability and response of composite wings in subsonic compressible flow.

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The necessity of increasing the utilization of renewable energies and lowering the dependence on fossil energies for power generation has been increasingly regarded worldwide. Thanks to its desirable solar radiation potential, Iran can lower its level of dependence on fossil fuels for power generation significantly by developing distributed solar photovoltaic (DSPV) systems. The present research began with identifying, through a literature review, relevant business models in terms of ownership and control and the barriers encountered by the PV industry. Continuing with the research, semi-structured interviews were performed with elites in the power industry to explore different barriers hindering the development of DSPV in Iran and weigh them appropriately. Next, according to the elites’ opinions, three business models differing in ownership and control were compared and scored in terms of their ability to address the identified barriers. According to the results, the business model with customer/third party ownership and utility control was identified as the most appropriate business model in Iran. As a final discussion, the business canvas and the roles and associations of all players of this industry in relation to the development of DSPV in Iran were explained.