CFD simulation of the IAEA 10 MW generic MTR reactor under loss of flow transient

Three-dimensional simulation of the IAEA 10 MW generic reactor under loss of flow transient is introduced using the CFD code, Fluent. The IAEA reactor calculation is a safety-related benchmark problem for an idealized material testing reactor (MTR) pool type specified in order to compare calculational methods used in various research centers. The flow transients considered include fast loss of flow accidents (FLOFA) and slow loss of flow accidents (SLOFA) modeled with exponential flow decay and time constants of 1 and 25 s, respectively. The transients were initiated from a power of 12 MW with a flow trip point at 85% nominal flow and a 200 ms time delay. The simulation shows comparable results as those published by other research groups. However, interesting 3D patterns are shown that are usually lost based on the one-dimensional simulations that other research groups have introduced. In addition, information about the maximum clad surface temperature, the maximum fuel element temperature as well as the location of hot spots in fuel channel is also reported.     

Sensory,physicochemical and rheological properties of plant-based milk alternatives made from soybean,peanut, adlay,adzuki bean,oat and buckwheat

This study investigated the physicochemical and sensory properties of six types of plant-based milk alternatives prepared from soybean, peanut, adlay, adzuki bean, oat and buckwheat at a 1:9 grain-to-water ratio. The results revealed that all plant-based milk types had stable hydrocolloid systems, except for the buckwheat milk alternative that had undergone a gelatinisation process that affected its rheological and sensory properties. The pH values and total solid content of the prepared plant-based milk samples ranged between 6.60 to 6.83 and 2.13 to 8.17 g/100 mL, respectively. The sensory results showed that the overall liking score of adlay, adzuki bean and peanut milk alternative was 5.32, 5.30 and 6.10, respectively, suggesting a potential for commercial production. In conclusion, this investigation provides new insights on several new plant sources for plant-based milk alternatives. Further studies are required to investigate the digestibility and the nutritional effects expected from plant-based milk alternatives such as protein bioavailability, and the effects on human health compared to other animal milks.     

Effect of accelerated aging on the properties of some writing paper sheets

Writing papers made from kraft softwood pulp and bagasse dissolving pulp were subjected to thermal aging for different time intervals (24, 48, 72, 96 and 120h) and the resulting changes in their chemical, physical and submicroscopic properties were investigated. The crystallinity changes in these pulps during thermal aging were studied by X-ray diffractograms. The carboxyl content of the kraft softwood pulp increased with time of thermal aging up to 96h and then decreased with increasing aging time, while the carboxyl content of bagasse dissolving pulp increased during thermal aging up to 72h and then decreased after this time. The crystallinity of kraft softwood pulp increased gradually during thermal aging. However, in the case of bagasse dissolving pulp the crystallinity increased up to 72h and then decreased. All pulps were characterized by a reduction in the degree of whiteness and chain depolymerization during the time of thermal aging.     

An Efficient Numerical Scheme for Solving Multi‐Dimensional Fractional Optimal Control Problems With a Quadratic Performance Index

The shifted Legendre orthogonal polynomials are used for the numerical solution of a new formulation for the multi‐dimensional fractional optimal control problem (M‐DFOCP) with a quadratic performance index. The fractional derivatives are described in the Caputo sense. The Lagrange multiplier method for the constrained extremum and the operational matrix of fractional integrals are used together with the help of the properties of the shifted Legendre orthonormal polynomials. The method reduces the M‐DFOCP to a simpler problem that consists of solving a system of algebraic equations. For confirming the efficiency and accuracy of the proposed scheme, some test problems are implemented with their approximate solutions.     

Artificial Neural Networks Modeling of Ozone Bubble Columns: Mass Transfer Coefficient,Gas Hold-Up,and Bubble Size

This study aims at applying artificial neural network (ANN) modeling approach in designing ozone bubble columns. Three multi-layer perceptron (MLP) ANN models were developed to predict the overall mass transfer coefficient (k_La, s^?1), the gas hold-up (? _G , dimensionless), and the Sauter mean bubble diameter (d_S , m) in different ozone bubble columns using simple inputs such as bubble column's geometry and operating conditions. The obtained results showed excellent prediction of k_La, ? _G , and d_S values as the coefficient of multiple determination (R² ) values for all ANN models exceeded 0.98. The ANN models were then used to determine the local mass transfer coefficient (k_L , m.s^?1). A very good agreement between the modeled and the measured k_L values was observed (R² ?=?0.85).     

Simplified seismic life cycle cost estimation of a steel jacket offshore platform structure

The purpose of the present paper is to develop a simple methodology for seismic life cycle cost (LCC) estimation for a steel jacket offshore platform structure. This methodology accounts for accuracy of LCC modelling as well as simplicity of application. Accuracy is maintained through incorporating the effect of aleatory and epistemic uncertainties in the LCC estimation framework. Simplicity is achieved by using equivalent single-degree-of-freedom (ESDOF) system instead of the full structure and by eliminating full incremental dynamic analysis and fragility analysis. Instead, an approximate fragility curve and a localised incremental dynamic analysis curve are used along with a probabilistic simple closed-form solution for loss estimation. In the design of model structures, different bracing systems are used for the seismic design of the offshore platform, such as conventional and buckling-restrained braces. The proposed LCC methodology is validated through comparison with the results from a more rigorous method. It is found that even though the proposed methodology results in a slightly different solution compared to the reference method, the method can be used as an efficient tool for preliminary LCC evaluation of structures.     

利用测井曲线评价碎屑岩岩石物理参数——以埃及尼罗河三角洲El-Wastani气田上中新统为例

利用埃及尼罗河三角洲El-Wastani气田10口气井的测井数据,对该气田主要储集层上中新统Qawasim组和Abu Madi组进行岩石物理分析,利用测井参数交会图进行岩性分析,并评估泥质含量、孔隙度、含水饱和度、含油气孔隙体积等参数。分析各井中子孔隙度-密度交会图、中子孔隙度-无铀伽马交会图和岩性-饱和度交会图发现:下Abu Madi组主要为砂岩,偶夹页岩;Qawasim组主要为页岩,偶夹砂岩。利用参数交会图及无铀伽马测井结果,得到有效产层各参数的临界值分别为:泥质含量50%,孔隙度10%,含水饱和度70%。分别绘制了产层有效厚度、平均孔隙度、泥质含量、含水饱和度等参数的等值线图,综合分析发现,研究区Qawasim组和Abu Madi组碎屑岩为优质储集层,天然气有利聚集区呈北西—南东向展布,中部尤为有利。     

Directional Overcurrent Relays Coordination Restoration by Reducing Minimum Fault Current Limiter Impedance

FCL （fault current limiter） is used to solve relays miscoordination problem arises from DG （distributed generation） installation. In most published researches, different optimization methods are developed to obtain optimal relay settings to achieve coordination in case of not installing DG, then depending on the achieved optimal obtained relay settings, FCL impedance is deduced to ensure relays coordination restoration in case of installing DG. Based on original optimal relay settings, obtained FCL impedance is not the minimum one required to achieve relay coordination. The contribution of this paper is the generation of multi sets of original relay settings that increase the possibility of finding FCL impedance of minimum value which is lower than the calculated value based on original optimal relay settings. The proposed method achieves better economic target by reducing FCL impedance. The proposed approach is implemented and tested on IEEE-39 bus test system.     

Utilisation of beef lung protein powder as a functional ingredient to enhance protein and iron content of fresh pasta

Beef lungs are an underutilised co-product of the meat industry that could be used as an ingredient to supplement the protein content of cereal foods. Beef lung powder (BLP) had a protein content of 87% (dry weight basis), an amino acid score of 1, and contained 1 mg g⁻¹ iron. Fresh semolina pasta was used as a model food, and BLP was incorporated up to 20%. Incorporation of 10% BLP improved the indispensable amino acid score of the pasta from 0.48 to 0.91. At that level of incorporation, higher cooking loss and redder (increased ‘a’ value) and darker (decreased ‘L’ value) colour resulted. The fresh pasta with BLP had a lower glycaemic response compared to control samples. BLP improved the functional value of the fresh pasta and is a potential ingredient in the development of new food products.