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The methods of the nanofluid flows modeling are analyzed. In the first part of the paper, methods for simulating flows of gas nanosuspensions are systematically considered. It is shown when they should be described by kinetic or continuum equations. Particular attention is paid to situations in which the nanofluid flows need to be described by a mixed kinetic-hydrodynamic method. In the second part the thermophysical properties (viscosity and thermal conductivity) of nanofluids are discussed in detailed. It was shown that the transport coefficients of nanofluids depend not only on the volume concentration of the particles but also on their size and material. The viscosity increases with decreasing the particle size while the thermal conductivity increases with increasing the particle size. The last part of the paper deals with modeling the mixing in micromixure and convection heat transfer in the tube. In conclusion, we discuss the applicability of various commonly used similarity criteria, such as Reynol...

Energy generation through wind energy conversion systems (WECS) is expected to supply a considerable amount of electricity in the world's generation matrix. In this context, variable-speed wind turbines equipped with full-scale power electronic converters allow a WECS to be operated close to its maximum power point at each time instant. Furthermore, modern power converter guarantee high power quality, high conversion efficiency levels, reliability and flexibility. This work reviews and compares two types of modulation schemes to two novel ones that are able to drive a Δ-switch rectifier. The presented theoretical analysis is based on a WECS application. Circuit simulation and experimental results verify the operation with the considered strategies. It is shown that one of the novel sub-optimal modulation patterns presents very high performance without the need of a precise sector identification scheme.

Higher participation levels of wind power in power systems will increase the need for flexible back-up generation to balance the differences between predicted and realized wind power production. This is often an expensive solution. With distributed energy resources and more ICT at the demand side, novel, and possibly cheaper, ways for imbalance minimization arise. Micro combined heat-and-power (micro-CHP) is a novel domestic-level generation technology, producing heat and power simultaneously. Clusters of micro-CHPs can function as flexible virtual power plants (VPPs). This paper presents the design of an online coordination scheme that can substantially reduce the imbalance volumes and the associated costs for wind power traders by actively controlling a VPP comprising micro-CHP systems. It is shown that the imbalance volume and associated cost can be reduced by 73 % and 38 %, respectively.

This paper researched the impacts of the built environment on local electricity consumption in metropolitan areas through a contextual investigation of Giza Governorate in Greater Cairo Metropolitan Region GCMR), Egypt. Basic Equation Modeling was used for the investigation on the causality of residential utilizations of power. The impacts of significant drivers theoretically causing the local vitality utilization, for example, family socio socioeconomics, family perspectives, family unit responsibility for, and assembled condition were inspected. Main results were the built environment associated to a settlement such as number of rooms and floor area in the settlement considerably influences the domestic electricity consumption; and the population density has considerable positive influences on the domestic electricity consumption. Findings of this paper propose that a design of built environment could take part in managing the domestic energy consumption in developing metropolitan regions which could be an effective tool to adapt the climate change ultimately.

© 2017 The Authors. Published by Elsevier Ltd. The UltraSTEEL dimpling forming process forms plain steel sheets into dimpled steel sheets, which have higher energy absorption performance. The energy absorption performance of dimpled products can be further improved through optimizing the forming depth in the UltraSTEEL process. In this paper, forming depths have been optimized through numerical simulations. Explicit dynamics finite element simulations were carried out to analyze the effect of forming depth on material properties as well as the effect of geometry on energy absorption separately. It has been found that yield strengths are maximized when the forming depth is approximately 1mm, and the energy absorption performance is optimized when the forming depth is approximately 0.9 times of the gauge thickness.

As the deployment of onshore wind turbines becomes established and with an increasing deployment of offshore wind turbines, to ensure a high reliability and availability of these machines has become the focus of interest within the academic and industrial communities. One of the approaches to meet this requirement is to develop a Reliability Centered Maintenance (RCM) strategy with the aid of an advanced condition monitoring and reliability prediction system. The aim of this paper is to describe the basic idea of how wind farm Supervisory Control and Data Acquisition (SCADA) system contributes to establishing such a strategy. Examples have been given in the paper for providing a clear explanation of the opinions.

De vraag is hoe vlees in de keten op een andere manier tot waarde kan worden gebracht en zodanig dat dit lonend is voor de partijen in de keten. Het project ‘Verdienmodellen’ richt zich op het ontwikkelen en beoordelen van alternatieve businessmodellen met een ander ‘waarde(n)perspectief’ voor de vleesketens kip en varkensvlees(producten).

Given the inherent ecological damage associated with post-industrial sites, their remediation offers an opportunity to apply the concept of symbiotic urbanism, a type of urban development that not only prevents ecological degradation, but also restores the natural environment while concurrently benefitting adjacent communities and economies, to their rehabilitation. Analogous to symbiotic urbanism, definitions of regenerative urban development and regenerative cities capture the notion of urban development that goes beyond preventing environmental damage to also encompass the replenishment of natural resources, but few case studies of how the entirety of the idea can be implemented exist. In contrast to commonly referenced examples of regenerative urban development this paper will discuss an application of symbiotic urbanism that offers a proposal for the comprehensive rehabilitation of a post-industrial site. The proposal uses the site’s industrial legacy as inspiration for entering a new era of production that engages in the research and development of innovative technologies that simultaneously remediate existing environmental degradation while stimulating new economies and opportunities and reconnecting communities to long-abandoned places.

The American Clean Energy and Security Act of 2009 (H.R. 2454) introduces a combined federal standard for efficiency and renewable electricity. This standard requires utilities to supply a portion of their customer’s demand using energy efficiency measures and renewable electricity generation. (1) This manuscript discusses an analysis conducted on the effect of H.R. 2454 on Texas’s electricity generation mix. In order to benchmark the net opportunity for energy efficiency, this analysis includes the historical trends in electricity consumption by sector and per capita for two states, Texas and California. This manuscript contains discussion on findings in two key areas. First, the overall consumption patterns seen historically in Texas compared to California including key differences found in each sector: residential, industrial and commercial/other. Second, the factors that contributed to these patterns including policy mechanisms, technological advances, and shifts in industry that contributed to these patterns. These findings are then applied to electricity consumption and generation mix projections in Texas. Evaluating these projections reveals the potential environmental impacts of H.R. 2454 on Texas.

Basic characterization of the waste management process during decommissioning of nuclear installations is described in the presented paper. Conditional and unconditional releasing of radioactive materials into the environment (ENV) is described in detail. By conditional release, significant volumes of steel can be released and valuable space in repository can be saved as well as costs for processing of metals as radioactive waste. Metal melting as a prospective decontamination technique of radioactive scrap metal is described in detail. Metal melting provides high decontamination factors for several radionuclides. Using metal melting, significant amounts of steel can be decontaminated and released into the ENV for recycling and reuse. However, the dark side of this technology are high investment costs and high operational costs. The next chapter deals with the disposal of materials classified as radioactive wastes. In this chapter types of disposal facilities are briefly described. In the last part of this paper three scenarios related to conditional releasing of steel are described. Basic descriptions of each scenario and results for the most significant radionuclide are given.