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Widespread commercialization of PCM-based latent heat storage systems is limited by the low melting and solidification rates during the phase transition process. In this study, fins are used to enhance the phase change process. A parametric study is conducted to understand the effect of fins on the thermal performance of vertically- and horizontally-oriented rectangular storage tanks. Throughout simulations, the fin volume, and thereby the mass of PCM in the tank, were kept constant. It was observed that the horizontal enclosures can take advantage of the development of strong natural convection flow until near the end of the melting process, whereas with vertical counterparts the strength of the convection currents was diminished during the shrinkage stage. The results suggest that longer and thinner fins are more beneficial for enhancing the melting rate than shorter and thicker fins. It was concluded that for horizontal enclosures with fin lengths of 25 and 35 mm, increasing the number of fins does not necessarily shorten the melting time. The maximum melting time reduction compared to the 3-fin vertical enclosure with a fin length of 25 mm (chosen as our benchmark case) was 75.1% when nine 45-mm-long fins are used in a horizontal enclosure. Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public. Process and Energy

Abstract Natural gas distribution network aims at delivering sufficient gas flow to consumers at consumption nodes. A gas meter is installed at each consumption node of gas network which records low frequency monthly gas consumption of that node. There is also a gas meter in city gate station which records high frequency daily gas consumption of the entire network. Gas distribution companies need to know daily gas consumption of each node (consumer) and daily nodal pressure of the network for control and planning purposes. Gas consumption of each node is a time series with constant recording time step. This article presents a time series disaggregation method for related time series with identical recording times. This method disaggregates low frequency gas consumption at the nodes to high frequency consumption such that sum of consumption of all nodes in each day equals daily consumption of the entire network measured by the city gate station gas meter in that day. These high frequency data are high frequency profile of consumers' gas consumption and can give analysis of the network. The article also discusses compatibility of low frequency consumption of gas network and city gate station high frequency data and the required corrections when these data are mismatched in mathematical sense. Finally, the method is applied to a gas distribution network and results are presented and discussed. The proposed method is general and can be applied to any set of related or unrelated time series and any network with known governing equations as well as the gas network.

The purpose of this paper is to streamline the supply of corn, one of the key ingredients in the production of bioethanol. Using a comprehensive sustainable framework of criteria (including social, economic, and environmental dimensions), the potential locations of corn cultivation in Iran are examined from a multi-criteria decision analysis perspective. To this end, we need to find the importance of the relevant evaluation criteria and a ranking method to rank the potential locations. Best worst method (BWM) is used to determine the weight of the criteria presented in the framework based on the opinion of a sample of Iranian experts, after which the ‘preference ranking organization method for enrichment evaluations II’ (PROMETHEE II) is applied to ranking the different provinces of Iran. To improve the ranking results, we extend the PROMETHEE II by employing a set of piecewise linear value functions, for which the performance of alternatives with respect to the criteria calculated by the piecewise linear value functions is used to determine the amount of deviation in the first step of PROMETHEE II. The results of the hybrid methodology indicate that the presence of water, land cost and air pollution are the most important factors determining the ranking of the alternatives, and that Kordestan is the best province for corn cultivation in Iran.