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The purpose of this study is to numerically investigate the influence of corner radius on the flow around two square cylinders in tandem arrangements at a Reynolds number of 100.

Six models of square cylinders with corner radii R/D = 0.0, 0.1, 0.2, 0.3, 0.4 and 0.5 (where R denotes the corner radius and D denotes the characteristic dimension of the body) were studied using an immersed boundary-lattice Boltzmann method, and the results were compared with those obtained using a two-dimensional unsteady finite volume method. The cylinders were mounted in a tandem configuration (1.5 ≤ L/D ≤ 10 where L denotes the in-line separation between the cylinder centers). The simulated models were quantitatively compared to the aerodynamic force coefficients and Strouhal number. Furthermore, qualitative analysis is presented in the form of flow streamlines and vorticity contours.

The R/D and L/D values were varied to observe the variation in the flow characteristics in the gap and wake regions. The numerical results revealed two different regimes over the spacing range. The drag force on the downstream cylinder was negative for all corner radii values when the cylinders were placed at L/D = 3.0 (a single-body system). Subsequently, a sudden increase was observed in the aerodynamic forces (drag and lift) when L/D increased. A different gap value was identified in the transformation from a single-body to a two-body system for different corner radii. To verify the single-body system, a simulation was carried out with a single cylinder having a longitudinal geometric dimension equal to the tandem arrangement (L/D + D). Furthermore, in a single-body regime, the total drag of a tandem cylinder was less than that of a single cylinder, thus demonstrating the benefits of using tandem structures. A significant reduction in the aerodynamic forces and drag force was achieved by rounding the sharp corners and placing the cylinders in close proximity. An appropriate configuration of the tandem cylinders with a rounded corner of R/D = 0.4 and 0.5 at L/D = 3.0 and the range is enhanced to L/D = 4.0 for 0.0 ≤ R/D < 0.4 to achieve adequate drag reduction.

To the best of the author’s knowledge, there is a paucity of studies examining the effect of corner radius on bluff bodies arranged in a tandem configuration.

The studies which connect international marketing emotions with perceived service quality are scarce. The purpose of this paper is to fill this knowledge gap and take into account the consumers’ perceived animosity, religiosity, and ethnocentrism to connect these with perceived service quality and purchase intentions of US-based fast food brand chains currently operating in Pakistan.

The authors collected data by means of a self-administered questionnaire, distributed among 500 consumers, randomly selected, patronized the four US fast food brands, namely, McDonalds, KFC, Pizza Hut, and Subway in the city of Lahore in Pakistan. The data are analyzed by employing Structural equation modeling (SEM) based on AMOS 21.0 software.

Results of this study reveal that religiosity and ethnocentrism among Pakistani fast food consumers are low and do not influence the decision to purchase fast food brands. However, consumer emotions influence service quality perceptions – ultimately leading to purchase intentions.

The study generally adds to marketing and specifically to international food service marketing knowledge by eliciting the role of religiosity, animosity, and ethnocentrism to delineate service quality and purchase intentions. Furthermore, the external validity of PAKSERV scale and the context of Pakistan – a collectivist Muslim country are also the unique products of this study.