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In this article we show a refueling strategy analysis using different injector configurations to refuel a 70 MPa composite reinforced type 4 tank. The gas has been injected through single openings of different diameters (3 mm, 6 mm and 10 mm) and alternatively through multiple small holes (4 × 3 mm). For each injector configuration, slow (12 min) and faster (3 min) fillings have been performed. The gas temperature has been measured at different positions inside the tank, as well as the temperatures of the wall materials at various locations: on the external surface and at the interface between the liner and the fiber reinforced composite. In general, the larger the injector diameter and the slower the filling, the higher the chance that the gas develops vertical temperature gradients (a so-called gas temperature stratification), resulting in higher than average temperatures near the top of the tank and lower than average at its bottom. While the single 3 mm opening injector causes homogeneous gas temperatures for both filling speeds, both the 6 mm and 10 mm opening injectors induce gas temperature stratification during the 12 min fillings. The injector with multiple holes has an area comparable to the 6 mm single opening injector: in general, this more complex geometry tends to limit the inhomogeneity of gas temperatures during slow fillings. When gas temperature stratification develops, the wall materials temperature is also locally affected. This results in a higher than average temperature at the top of the tank and higher the slower the filling. [ABSTRACT FROM AUTHOR]

The influence of the initial tank temperature on the evolution of the internal gas temperature during the refuelling of on-board hydrogen tanks is investigated in this paper. Two different types of tanks, four different fuel delivery temperatures (from ambient temperature refuelling to a pre-cooled hydrogen at −40 °C), several filling rates and initial pressures are considered. It has been found that the final gas temperature increases linearly with the increase of the initial tank temperature while the temperature increase (ΔT) and the final state of charge (SOC) decrease linearly with increasing the initial temperature. This dependency has been found to be larger on type III than on type IV tank and larger the larger the initial pressure. Additionally CFD simulations are performed to better understand the role of the relevant phenomena on the gas temperature histories e.g. gas compression, gas mixing, and heat transfer. By comparing the results of calculations with adiabatic and diathermal tank walls, the effect of the initial gas temperature has been separated from the effect of the initial wall temperature on the process. [ABSTRACT FROM AUTHOR]

During the driving of a fuel cell car, the expansion of the hydrogen along the emptying of the high pressure storage tank produces a cooling of the gas. The hydrogen vessel can experience a fast depressurization during acceleration or under an emergency release. This can result on the one hand in exceeding the low safety temperature limit of −40 °C inside the on-board compressed hydrogen tank and on the other hand in the cooling of its walls. In the present paper, defueling experiments of two different types of on-board hydrogen tanks (Type III and Type IV) have been performed in all the range of expected defueling rates. The lowest temperatures have been found on the bottom part of the Type IV tank in very fast defuelings. For average driving conditions, in both types of vessels, the inside gas temperature gets closer to that of the walls and the tank would arrive to the refuelling station at a temperature significantly lower than the ambient temperature. [ABSTRACT FROM AUTHOR]

The thermal behaviour of several commercial hydrogen tanks (Type III and Type IV) has been studied during high pressure hydrogen cycling (filling from 2 – 3 MPa to 78 – 84 MPa, holding under pressure and emptying back to 2 – 3 MPa). The temperature of the gas at different points inside the tank, the temperature at the bosses and at the tanks outer surface has been measured during several hydrogen cycles. From the experimental results, the evolution of the measured gas temperatures during the complete cycling process has been studied. The effect of the filling rate on the temperature increase of the gas during the filling has been evaluated. The thermal response of the metallic bosses and the external surface of the tanks under different cycling conditions have also been investigated. The evolution of the external temperature has been correlated to the evolution of the gas temperature. The influence of the manufacturing materials on the thermal behaviour of the tank, the importance of the initial thermal state of the tank in the refuelling process and the difficulty of filling a Type IV tank without pre-cooling in a reasonable amount of time have been highlighted in the present work. The possibility of monitoring the external temperatures of the tank to follow the evolution of the inside gas temperature during the filling and emptying phases has also been considered. [ABSTRACT FROM AUTHOR]

Abstract: Toxoplasma gondii is an obligate intracellular parasite and the causative agent of toxoplasmosis. Protein palmitoylation is known to play roles in signal transduction and in enhancing the hydrophobicity of proteins thus contributing to their membrane association. Global inhibition of protein palmitoylation has been shown to affect T. gondii physiology and invasion of the host cell. However, the proteins affected by this modification have been understudied. This paper shows that the small heat shock protein 20 from T. gondii (TgHSP20) is synthesized as a mature protein in the cytosol and is palmitoylated in three cysteine residues. However, its localization at the inner membrane complex (IMC) is dependent only on N-terminal palmitoylation. Absence or incomplete N-terminal palmitoylation causes TgHSP20 to partially accumulate in a membranous structure. Interestingly, TgHSP20 palmitoylation is not responsible for its interaction with the daughter cells IMCs. Together, our data describe the importance of palmitoylation in protein targeting to the IMC in T. gondii. [Copyright &y& Elsevier]

Short refueling time and high final state of charge are among the main hydrogen car user's requirements. To meet these requirements, without exceeding the tank materials safety limits, hydrogen precooling is needed. Filling experiments with different inlet gas temperatures and mass flow rates have been executed using two different types of on-board tanks (type 3 and 4). State of charge has a strong dependency on the inlet gas temperature. This dependency is more visible for type 4 tanks. Lowest precooling temperature (−40 °C) is not always required in order to meet user's requirements, so energy savings can be achieved if the initial conditions of the tank are correctly identified. The results of the experiments performed have been compared with the SAE J2601 look-up tables for non-communication fillings. A big safety margin has been observed in these tables. Refueling could be performed faster and with less demanding precooling requirements if the initial conditions and the configuration of the hydrogen storage system are well known. [ABSTRACT FROM AUTHOR]

At the JRC-IET, on-board hydrogen tanks have been subjected to filling–emptying cycles to investigate their long-term mechanical and thermal behaviour and their safety performance. The local temperature history inside the tanks has been measured and compared with the temperatures outside and at the tank metallic bosses, which is the measurement location identified by some standards. The outcome of these activities is a set of experimental data which will be made publicly available as reference for safety studies and validation of computational fluid dynamics. [ABSTRACT FROM AUTHOR]

Abstract This article portrays the European Commission's High Pressure Gas Tank Testing Facility (GasTeF), which is located at the Joint Research Centre in Petten (the Netherlands). GasTeF is one of the few facilities in Europe where research is conducted on on-board compressed hydrogen storage systems. The GasTeF facility is designed to carry out pneumatic hydrogen cycle and permeation tests according to the procedures prescribed by type approval regulations. GasTeF is as well suited for performing experiments replicating the refuelling of on-board hydrogen tanks also simulating out-of-specification operating conditions of a hydrogen fuelling station. With this research, the Gas Tank Testing Facility supports JRC's mission to provide policy makers and stakeholders with independent assessments of hydrogen technologies in terms of performance efficiency, safety and reliability. Highlights • Description of equipment for a compressed hydrogen tank testing facility. • Safety systems and procedures for a compressed hydrogen tank testing facility. • GasTeF testing capabilities of compressed hydrogen tanks. • Summary of GasTeF scientific production. [ABSTRACT FROM AUTHOR]