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Showing papers by "Ephraim M Sparrow published in 2014"


Journal ArticleDOI
TL;DR: In this article, a model and simulation for the entry of a sphere into a water surface from an air space above the surface is presented, and the model is validated by comparison with extensive experimental data and with trends from approximate analyses.

56 citations


Journal ArticleDOI
01 Aug 2014-Burns
TL;DR: It was demonstrated that values of CEM43 at the basal layer of the skin were highly correlated with the depth of injury calculated from a thermal injury integral, and it was shown that the cell survival/CEM43 relationship for the cases investigated here most closely aligns with isothermal exposure of tissue to temperatures of ~50 °C.

55 citations


Journal ArticleDOI
TL;DR: In this article, a synergistic use of numerical simulation and experimentation is presented to provide both in-depth fluid mechanics fundamentals and results for applications, and experimental results validated the choice of the turbulence model.

48 citations


Journal ArticleDOI
TL;DR: In this article, numerical simulation has been used to investigate a number of significant physical processes for reverse osmosis in a spiral-wound membrane, including fluid flow regimes, flow unsteadiness, and fluid flow periodicity.

23 citations


Journal ArticleDOI
TL;DR: In this article, the authors compare the life cycle impacts of two distinct logistical approaches to packaging commonly used in cold chain logistics and identify the method of least environmental burden in a 2-year clinical trial consisting of 30,000 individual package shipments at a controlled 2-8°C temperature range for approximately 96h.
Abstract: Pharmaceutical and biological materials require thermally controlled environments when being transported between manufacturers, clinics, and hospitals. It is the purpose of this report to compare the life cycle impacts of two distinct logistical approaches to packaging commonly used in cold chain logistics and to identify the method of least environmental burden. The approaches of interest are single-use packaging utilizing containers insulated with either polyurethane or polystyrene and reusable packaging utilizing containers with vacuum-insulated panels. This study has taken a cradle-to-grave perspective, which covers material extraction, manufacture, assembly, usage, transportation, and end-of-life realities. The functional unit of comparison is a 2-year clinical trial consisting of 30,000 individual package shipments able to maintain roughly 12 L of payload at a controlled 2–8 °C temperature range for approximately 96 h. Published life-cycle inventory data were used for process and material emissions. A population-centered averaging method was used to estimate transportation distances to and from clinical sites during container use. Environmental impacts of the study include global warming potential, eutrophication potential, acidification potential, photochemical oxidation potential, human toxicity potential, and postconsumer waste. The average single-use approach emits 1,122 tonnes of CO2e compared with 241 tonnes with the reusable approach over the functional unit. This is roughly a 75 % difference in global warming potential between the two approaches. Similar differences exist in other impact categories with the reusable approach showing 60 % less acidification potential, 65 % less eutrophication potential, 85 % less photochemical ozone potential, 85 % less human toxicity potential, and 95 % less postconsumer waste. The cradle-to-gate emissions of the single-use container were the overwhelming cause of its high environmental burden as 30,000 units were required to satisfy the functional unit rather than 772 for the reusable approach. The reusable container was about half the mass of the average single-use container, which lowered its transportation emissions below the single-use approach despite an extra leg of travel. The reusable logistical approach has shown to impose a significantly smaller environmental burden in all impact categories of interest. A sensitivity analysis has shown some leeway in the degree of the environmental advantage of the reusable approach, but it confirms the conclusion as no case proved otherwise.

23 citations


Journal ArticleDOI
TL;DR: In this paper, a method was proposed for determining temperatures within boreholes and the surrounding rock both during and after the drilling operation, and it was found that the coolant temperature is dependent upon location within the borehole, and the relaxation time of rock temperatures to their equilibrium values varies with depth in the hole.

14 citations


Journal ArticleDOI
TL;DR: In this paper, the authors investigated the heat transfer and fluid flow characteristics of rectangular slot jets which experience jet-axis switching and showed that the jet cross sections evolve through near circularity and subsequently become skewed in the direction perpendicular to that of the initial skewness.

10 citations


Journal ArticleDOI
TL;DR: In this article, the authors developed and implemented a numerical simulation model to predict the outcome of the thermochemical ablation therapy of tumors and other dysfunctional tissue, which includes a reaction zone whose volume is defined by the volume of the chemical reagents and a surrounding volume of tissue to be necrosed.
Abstract: The goal of this investigation is to develop and implement a numerical simulation model to predict the outcome of the thermochemical ablation therapy of tumors and other dysfunctional tissue. The simulation model formulated here includes a reaction zone whose volume is defined by the volume of the chemical reagents and a surrounding volume of tissue to be necrosed. Account is taken of the relevant macroscopic thermal processes of conduction, perfusion, metabolism, and internal energy storage/depletion. The zone of necrosed tissue is quantified by means of the Henriques-Moritz thermal damage integral. The simulation model was confirmed by comparisons with available experimental data. The main results extracted from the simulations are the temporal and spatial temperature variations throughout the tissue bed and the resulting distributions of necrosed and non-necrosed tissue. The radius of the zone of necrosis was algebraically correlated with the heat of reaction of the participating reagents. It was demon...

6 citations


Journal ArticleDOI
TL;DR: It was found that the presence of unaccounted embedments affected the pressure drop predictions for the system by 14-19% and this outcome suggests that deviations between experimental and simulation results encountered in the literature might well have been due to geometrical deviations of the type investigated here.

1 citations


Journal ArticleDOI
22 May 2014
TL;DR: In this paper, a tissue test specimen, biological muscle sample, was positioned in a precisely temperature-controlled environment and irradiated with 532-nm laser light, the absorbed radiation gave rise to thermal expansion whose induced stresses created a sound field which was detected by a piezoelectric sensor.
Abstract: The capabilities of the optoacoustic principle as a means of temperature measurement have been explored by means of experiments. In the experiments, a tissue test specimen, biological muscle sample, was positioned in a precisely temperature-controlled environment and irradiated with 532-nm laser light. The absorbed radiation gave rise to thermal expansion whose induced stresses created a sound field which was detected by a piezoelectric sensor. During the course of the experiments, the temperature of the water bath was systematically varied, with ample time being allowed to enable the test specimen to achieve thermal equilibrium. The temperature variation encompassed both increasing and decreasing protocols. Replicate samples were tested to ensure accuracy. It was found that temperature increases gave rise to decreasing acoustic amplitudes. An opposite trend was observed when the temperature was decreased. This outcome, when compared with the published literature, suggested that accurate use of the photoacoustic effect as a means of temperature measurement requires great care in the setup and execution of the experiment.