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Novel aircraft propulsion configurations require a greater integration of the propulsive system with the airframe. As a consequence of the closer integration of the propulsive system, higher levels of flow distortion at the fan face are expected. This distortion will propagate through the fan and penalize the system performance. This will also modify the exhaust design requirements. This paper aims to propose a methodology for the aerodynamic optimization of the exhaust for novel embedded propulsive systems. To model the distortion transfer, a low order throughflow fan model is included.

As the case study a 2D axisymmetric aft-mounted annular boundary layer ingestion (BLI) propulsor is used. An automated computational fluid dynamics approach is applied with a parametric definition of the design space. A throughflow body force model for the fan is implemented and validated for 2D axisymmetric and 3D flows. A multi-objective optimization based on evolutionary algorithms is used for the exhaust design.

By the application of the optimization methodology, a maximum benefit of approximately 0.32% of the total aircraft required thrust was observed by the application of compact exhaust designs. Furthermore, for the embedded system, it is observed that the design of the compact exhaust and the nacelle afterbody have a considerable impact on the aerodynamic performance.

This paper presents a novel approach for the exhaust design of embedded propulsive systems in novel aircraft configurations. To the best of the authors’ knowledge, this is the first detailed optimization of the exhaust system on an annular aft-mounted BLI propulsor.

The study aims to empirically analyze the effects of the presence of female top managers and owners on corporate tax compliance.

Data for analysis were sourced from the World Bank Enterprise Surveys that involved 23,178 private firms in 98 countries. The surveys used a stratified random sampling method by using three criteria, namely, firm size, business sector and geographic region, within each country. Further, data are analyzed using the ordinal logistic regression and supported by the marginal effect analysis.

The results show that the presence of female top managers and owners is a significant factor that underlies the firm-level tax compliance difference when firms exhibit relatively lower compliance.

Although this study shows that the determinants of corporate tax compliance are very complex, there are also crucial roles of top managers and owners' gender. This study advises firms to use the gender equality strategy to generate the best human capital, especially in their top management levels. Besides, this study can be helpful in designing policies that facilitate women to reach top managerial levels or to own businesses as an alternative method to enhance tax compliance for developing countries that fail to generate optimal corporate income tax revenues.

To the best of the authors’ knowledge, no previous studies examine the effects of the presence of female top managers and business owners on firms’ tax compliance policies. This study contributes to extend the understanding of the important role of women in corporate strategic decision-making, especially in taxation policies in various developing countries.