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Turboshaft engines usually include one centrifugal compressor due to its high-pressure ratio, stability and compactness. Many designers rely on positive raking to decrease tip gap flow and therefore losses. However recent optimization studies revealed geometries contradicting this canonic view. Hence, this paper aims to investigate how the rake angle alone can influence performance and to which extent.

A turboshaft representative impeller was chosen and altered for null and +/−30° rake angles. Menter's shear stress transport model is used for steady computational fluid dynamics simulations, sweeping the nominal speedline at various tip clearances. Backsweep distribution is identical in all cases, isolating rake influence.

Pressure ratio was lowered for the both positively and negatively raked blades, but through distinct aerodynamic mechanisms. Although the flow through the tip gap was lower for the positive rake, this is due to lower blade loading. Splitter comparison reveal that these effects are more pronounced in the radial regions.

Some of the findings may extend beyond turboshaft engines, into turbochargers, home appliances or industrial blowers. However, all extrapolations must consider specific differences between these applications. Turboshaft compressors designers can benefit from this study when setting up their free parameters and penalty functions in the early concept stages.

Only few similar studies can be found in the literature to date, none similar to turboshaft applications. Also, this impeller is designed to eliminate leading edge shocks and suction side boundary layer separation, which makes it easier to isolate the tip gap flow effects. The authors also provide a framework on which semi-empirical design equations can be further developed to incorporate rake into 1D design tools.

Purpose: This study reviews the financial implications of ESG business model redesign, focusing on providing higher orientation to ESG principles for firms’ supply chains, including training needs, policy requirements, or monitoring tool implementation. It assesses the association between firms’ profitability and the efforts firms make to align with principles of sustainable business models.

Methodology: Several statistical analyses, including canonical analysis, ANOVA, and multiple regression analysis. The focus of the research is limited to the CAER ex-communist members.

Findings: There is significant reluctance from the firms’ side to make the transition to the ESG-based and more circular economy business models when reviewing data about ESG supply chains, mainly driven by insufficient know – how transferred on the firm level from the academic side and insufficient understanding on the cost-benefits analysis of such transition.

Implications: Better resource allocation, increased environmental innovation capital acquisitions, or reduced waste along business processes lead to increased firms’ profitability. Transformation driven by the transition to circular business models also involves supply chain management-related business processes. The direct impact of transforming supply chains on firms’ profitability depends especially on the business models, mainly described by the particularities of the sector firms operate in, by countries’ institutional framework, and potential for growth. The green transformation of supply chains also generates indirect effects on firms’ profitability.

Limitations: Data selected for the study is extracted from the Refinitiv database, namely, all the listed companies with assets valued over 10,000 EUR from ex-communist economies.

Future Research: An extended database.

This study aims to identify how Spanish consumers’ extrinsic preferences for food have evolved by examining the extant literature on food preferences in Spain, focusing on food-related attributes and food-related values.

This study is based on a synthetic review of the extant academic literature on Spanish consumer preferences for food-related attributes and food-related values from the mid-20th to the 21st century. This study uses key economic and social milestones that are most likely to influence food value chain actors to show how consumer preferences have evolved over the study period.

Spanish consumer food attribute preferences expanded as the food sector of the nation continued to grow, and value preferences showed a similar pattern from the mid-20th to the 21st century. The drivers of these preferences were trust, lifestyle, education (campaigns), sociodemographic factors and purchasing power.

Evaluating the extant literature’s contribution to consumer preferences for food-related attributes and values is important because it can aid in understanding the hierarchy and variety of consumers’ food preferences as well as the factors that drive these preferences. To the best of the authors’ knowledge, this study is the first to explore how Spanish consumer preferences evolved between the mid-20th and 21st centuries.

The study investigates the inter-linkages between geopolitical risk (GPR) and food price (FP).

By employing the bootstrap full- and sub-sample rolling-window Granger causality tests.

The empirical results show that there is a time-varying bidirectional causality between GPR and FP. High GPR leads to a rise in FP, suggesting that geopolitical events usually may disrupt supply and demand conditions in food markets, and even trigger global food crises. However, the negative effect of GPR on FP does not support this view in certain periods. This is mainly because GPR is also related to the global economic situation and oil price, which together have impacts on the food market. These results cannot always be supported by the inter-temporal capital asset pricing model, which states that GPR affects FP in a positive manner. Conversely, there is a positive impact of FP on GPR, indicating that the food market is an effective tool that can reflect global geopolitical environment.

In the context of the Russia–Ukraine conflict, these analyses can assist investors and policymakers to understand the sensitivity of FP to GPR. Also, it will provide significant revelations for governments to attach importance to the role of food price information in predicting geopolitical events, thus contributing to a more stable international environment.