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Air impingement method has been widely used in a variety of industrial applications, such as textile and paper drying, turbine cooling, and glass quenching, because it is an efficient technology with high heat and mass transfer rates. This technology has received increasing interest in the field of food processing over the last two decades, such as drying, baking, blanching, freezing, and thawing. In a food processing equipment using air impingement, jets of high‐velocity air (with speeds of 10–50 m/s) are directed at a food product. The performance of the system is influenced by several critical elements, including jet velocity, nozzle array diameter and layout, jet distance, and boundary layer characteristics. The use of computational fluid dynamics, an emerging tool, has been shown to be valuable in the analysis of fluid flow and heat and mass transfer in jet impingement systems. The physical properties of impinging jets, such as turbulent mixing in the free jet zone, stagnation, boundary layer formation, recirculation, and their interactions with food products in terms of heat and mass transfer, have been discussed in this article. The benefits and disadvantages of air jet impingement technology in different food processing applications together with potential trends for improving impingement technology performance were identified and discussed. This review not only contributes to a better understanding of the research status of impingement technology on food processing but also triggers new research opportunities in this field in order to provide more healthy and nutritious food in a more sustainable way to the world's growing population. [ABSTRACT FROM AUTHOR]

In this study, we first identify seven criteria for the design of biomimetic robotic fish and focus on two of these tasks: shape and hydromechanics. For this purpose, fish body part measurements were obtained using previous work and also captured and harvested fish samples to construct computer-aided design (CAD) models of three fish species: Scomber scombrus , Sarda sarda , and Thunnus thynnus. Dead body drag and caudal fin flapping were considered as two separate problems. Computational simulations were carried out to determine drag and propulsive performance. Body drag simulations showed that the Reynolds dependence of the drag coefficient of three different species can be adequately expressed by a single laminar scaling correlation. At the same length and swimming speed, the Atlantic mackerel experiences the least drag. Caudal fin deformation simulations showed that the Atlantic bluefin tuna offers the highest thrust and efficiency. Peak efficiency is in the range of 31–35 percent observed at the same optimal Strouhal number, St = 0.5, for all species. It is shown that the aspect ratio as the main length scale influences propulsion performance. • CAD models of three fish species (Scomber scombrus , Sarda sarda , and Thunnus thynnus) were reconstructed from length measurements. • Reynolds dependence of the drag coefficient of three different species can be adequately expressed by a single scaling correlation. • At the same length and swimming speed, the Atlantic mackerel experiences the least drag. • Atlantic bluefin tuna offers the highest thrust and efficiency. • Peak efficiency is in the range of 31–35 percent observed at the same optimal Strouhal number. [ABSTRACT FROM AUTHOR]

In this article, the performance improvement of an in-line centrifugal fan obtained by utilizing outlet guide vanes is presented. For this purpose, numerical solutions were sought for Reynolds-averaged Navier–Stokes equations using a commercial finite-volume-based solver assuming three-dimensional, steady, viscous, and incompressible flow. Computational modeling was first verified by experiments that comply with the fan performance testing International Organization for Standardization Standard BS EN ISO 5801. Streamlines at the outlet revealed the necessity of guide vanes to eliminate the high circumferential velocity component and to recover static pressure rise. For this purpose, manufacturers employ flat plates welded on the fan chassis that carry the motor and the impeller. In the experiments, maximum fan efficiency was 17% without any flow straightener, whereas the flat plates increased the efficiency to 31%. Using the guide vanes designed in this study, the swirl at the outlet was almost completely eliminated, and the maximum efficiency was found to be 38%. [ABSTRACT FROM PUBLISHER]

We aimed to investigate the role of urinary bladder shape which may potentially change with advancing age, increased waist circumference, pelvic ischemia, and loosening of the urachus on bladder emptying and UFR. We retrospectively investigated the medical records of 76 men.The patients were divided into two groups according to bladder shapes in MRI scan (cone and spheric shapes). There was a significant difference between the two groups in terms of IPSS, Qmax, Qave, and waist circumference. A positive correlationhasbeendemonstratedbetweenmeanpeakurinaryflowratemeasuredwithUFMandmeanflowrate calculated using the CP. There was a significant difference between mean urinary flow rates calculated with CP of cone and sphere bladder shapes. The change in the bladder shape might be a possible factor for LUTS in men and LUTS may be improved if modifiable factors including increased waist circumference and loosening of the urachus are corrected. [ABSTRACT FROM AUTHOR]

A well known property of Oscillating Water Column (OWC) type wave energy converters is the approximately linear pressure drop-volume flow rate relation due to the Wells turbine equipment. This work presents a novel method where this relation is defined as a boundary condition in time domain simulations. The interaction of the OWC with regular, small waves in a tank is the boundary value problem that is under consideration. The finite volume method-based solver Fluent is used with two dimensional, incompressible, unsteady, two-phase flow assumptions. The turbine parameter that relates the pressure drop and flow rate is determined using linearised theory. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, the theoretical analysis of an alternative oscillating water column type wave energy converter is presented. The problem geometry differs from earlier two dimensional studies by a modification on the front wall where the surface piercing barrier is replaced with a fully submerged barrier with a gap. Linear Wave Theory is used to govern the fluid motion. Matched eigenfunction expansions and a Galerkin approximation are utilized and results are presented comparatively. Two optimization ideas for power conversion are discussed. First, optimization for all frequencies is considered with the usual assumption of linear, Wells-type air turbine characteristics. Next, results following the practical optimization idea of Lovas et al. are obtained where it is found that only one value for the turbine parameter can be sufficient to obtain efficiency very close to theoretical maximum for any wave frequency. It is also shown that by choosing geometrical parameters of the current problem appropriately, it is possible to obtain improvements on the efficiency curve of the OWC with a surface piercing barrier type front wall where both problems have the same resonant frequency. [Copyright &y& Elsevier]

Simulations are reported on the behavior of two tandem symmetric foils in an in-line configuration undergoing pitching motion. The Reynolds number was varied between 1000 and 4000, whereas the pitching Strouhal number ranged from 0.2 to 0.5 and the amplitude of pitching varied from 4 to 8 deg. The streamwise separation distance between the foils was fixed at one chord length. The performance of the downstream foil was significantly worsened (up to 80% in efficiency) by the tandem effects. The Strouhal number, Reynolds number, and pitching amplitude had substantial impact on the performance of the downstream foil. For the upstream foil, however, the performance improved by up to 147% in efficiency at all ranges of Reynolds number, Strouhal number, and pitching amplitude. The scaling of the individual foil performance metric and the system collective performance metric were investigated for tandem foils. The scaling developed for isolated foils does hold for tandem foils in the in-line configuration with modified empirical coefficients that depend on reduced frequency and Reynolds number in a range of St and Re. However, the leading foil behavior at lower St is more scattered compared to higher St, which suggests more significant wake interactions that influence the scaling and performance of the leading foil. [ABSTRACT FROM AUTHOR]

We aimed to investigate the role of urinary bladder shape which may potentially change with advancing age, increased waist circumference, pelvic ischemia, and loosening of the urachus on bladder emptying and UFR. We retrospectively investigated the medical records of 76 men. The patients were divided into two groups according to bladder shapes in MRI scan (cone and spheric shapes). There was a significant difference between the two groups in terms of IPSS, Qmax, Qave, and waist circumference. A positive correlation has been demonstrated between mean peak urinary flow rate measured with UFM and mean flow rate calculated using the CP. There was a significant difference between mean urinary flow rates calculated with CP of cone and sphere bladder shapes. The change in the bladder shape might be a possible factor for LUTS in men and LUTS may be improved if modifiable factors including increased waist circumference and loosening of the urachus are corrected.