The talk with present the key results of the IPCC Working Group III 5th assessment report. Concluding four years of intense scientific collaboration by hundreds of authors from around the world, the report responds to the request of the world's governments for a comprehensive, objective and policy neutral assessment of the current scientific knowledge on mitigating climate change. The report has been extensively reviewed by experts and governments to ensure quality and comprehensiveness.

Climate change 2014 - Mitigation of climate change

This chapter discusses leading problems linked to energy that the world is now confronting and to propose some ideas concerning possible solutions. Oil deserves special attention among all energy sources. Since the beginning of 1981, it has merely been continuing and enhancing the downward movement in consumption and prices caused by excessive rises, especially for light crudes such as those from Africa, and the slowing down of worldwide economic growth. Densely-populated oil-producing countries need to produce to live, to pay for their food and their equipment. If the economic growth of the industrialized countries were to be 4%, even if investment in the rational use of energy were pushed to the limit and the development of nonpetroleum energy sources were also pursued actively, it would be extremely difficult to prevent a sharp rise in prices. It is evident that it is absolutely necessary to pursue actively the development of coal, natural gas, and nuclear power if a physical shortage of energy is not to block economic growth.

World energy outlook

An introduction to heat transfer

Boundary-layer flow of a nanofluid past a stretching sheet

Nanofluids, the fluid suspensions of nanomaterials, have shown many interesting properties, and the distinctive features offer unprecedented potential for many applications. This paper summarizes the recent progress on the study of nanofluids, such as the preparation methods, the evaluation methods for the stability of nanofluids, and the ways to enhance the stability for nanofluids, the stability mechanisms of nanofluids, and presents the broad range of current and future applications in various fields including energy and mechanical and biomedical fields. At last, the paper identifies the opportunities for future research.

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A review on nanofluids: preparation, stability mechanisms, and applications

Pressure-tube and calandria-tube deformation following a single-channel blockage event in ACR-700

Propagating parameter uncertainty for a nuclear reactor system code is a challenging problem due to often non-linear system response to the numerous parameters involved and lengthy computational times; issues that compound when a statistical sampling procedure is adopted, since the code must be run many times The number of parameters sampled must therefore be limited to as few as possible that still accurately characterize the uncertainty in the system response A Quantitative Phenomena Identification and Ranking Table (QPIRT) was developed to accomplish this goal The QPIRT consists of two steps: a 'Top-Down' step focusing on identifying the dominant physical phenomena controlling the system response, and a 'Bottom-Up' step which focuses on determining the correlations from those key physical phenomena that significantly contribute to the response uncertainty The Top-Down step evaluates phenomena using the governing equations of the system code at nominal parameter values, providing a 'fast' screening step The Bottom-Up step then analyzes the correlations and models for the phenomena identified from the Top-Down step to find which parameters to sample The QPIRT, through the Top-Down and Bottom-Up steps thus provides a systematic approach to determining the limited set of physically relevant parameters that influence the uncertainty of the systemmore » response This strategy was demonstrated through an application to the RELAP5-based analysis of a PWR Total Loss of main Feedwater Flow (TLOFW) accident, also known as feed and bleed' scenario,  Ultimately, this work is the first component in a larger task of building a calibrated uncertainty propagation framework The QPIRT is an essential piece because the uncertainty of those selected parameters will be calibrated to data from both Separate and Integral Effect Tests (SETs and IETs) Therefore the system response uncertainty will incorporate the knowledge gained from the database of past large IETs (authors)« less

Quantitative Phenomena Identification and Ranking Table (QPIRT) for Bayesian Uncertainty Quantification

As a water-cooled nuclear system with a direct thermal cycle, the supercritical-water–cooled reactor (SCWR) shares with the boiling water reactor (BWR) the issue of coolant activation and transport...

Nitrogen-16 Generation and Transport and Associated Shielding Requirements in a Supercritical-Water–Cooled Reactor

Should Nuclear Energy Play a Role in a Carbon-Constrained World?

A multi-year project at the INEEL and MIT is investigating the potential of lead or lead-bismuth (lead-alloy) cooled fast critical reactors for producing low-cost electricity as well as for burning actinides from LWR spent fuel. While these two goals are the primary thrust in the development of a conceptual design, the proliferation resistance of the fuel and the plant safety are also important constraints incorporated into the design process. Thus, this concept addresses all Generation IV reactor goals, which involve favorable economics, enhanced safety, and sustainability. This paper outlines the objectives of the project, the challenges shaping the design strategy, and the approaches adopted to achieve the design goals. The most promising path forward is also identified. The four key factors that influence the direction of the design and also require compromise are the actinide destruction rate, safety, economy, and proliferation resistance. Achieving a maximum actinide destruction rate per MWth requires fertile-free fuels. However, the achievement of safe reactivity coefficients in such cores is difficult. If the total elimination of actinides from LWR spent fuel is pursued, multiple reprocessing with high recovery efficiency is necessary. This will probably significantly increase the fuel cycle costs, thus negatively affecting the economics. On the other hand, in-situ breeding and burning of plutonium in cores initially loaded with U235 can be cost effective. However, such a system does not achieve any reduction in the actinide inventory, and the discharge fuel contains relatively pure Pu239, which poses a potential proliferation threat. To reconcile these competing goals, a number of approaches have been investigated to achieve a balanced design that is cost competitive with other alternatives for electricity generation, attains excellent safety, helps in the reduction of transuranics from the spent LWR fuel, and has discharged fuel that is at least as proliferation resistant as spent LWR fuel from a once-through cycle. The preliminary design of the reactor concept that has the best potential to achieve these characteristics is identified and briefly described. This concept incorporates a supercritical carbon dioxide power conversion cycle that achieves thermal efficiencies up to 45% at a core outlet temperature of 550°C. However, conventional steam cycles are also an option.© 2002 ASME

Jacopo Buongiorno

Papers

Pressure-tube and calandria-tube deformation following a single-channel blockage event in ACR-700

Quantitative Phenomena Identification and Ranking Table (QPIRT) for Bayesian Uncertainty Quantification

Nitrogen-16 Generation and Transport and Associated Shielding Requirements in a Supercritical-Water–Cooled Reactor

Should Nuclear Energy Play a Role in a Carbon-Constrained World?

Design Strategies for Lead-Alloy-Cooled Reactors for Actinide Burning and Low-Cost Electricity Production