Energy dissipation downstream of Piano KeyWeirs – Case study ofGloriettes Dam (France)

2011 ◽  
pp. 123-130 ◽  
Author(s):  
M Bieri ◽  
M Federspiel ◽  
J Boillat ◽  
B Houdant ◽  
L Faramond ◽  
...  
Keyword(s):  
Energy Dissipation

Use of a stacked drop manhole for energy dissipation: a case study in Edmonton, Alberta

2009 ◽  
Vol 36 (6) ◽  
pp. 1037-1050 ◽  
Author(s):  
G. Adriana Camino ◽  
David Z. Zhu ◽  
Nallamuthu Rajaratnam ◽  
Manas Shome
Keyword(s):  
Energy Dissipation ◽  
Total Energy ◽  
Laboratory Investigation ◽  
Flow Regimes ◽  
Flow Patterns ◽  
The Other ◽  
Inflow Conditions ◽  
Water Depths ◽  
Total Energy Dissipation

This paper reports on a laboratory investigation into the performance of a novel stacked drop manhole design where two identical rectangular manholes are stacked one beside the other but at different heights so that there is a drop in elevation from one to the other. The focus of the study was to estimate the energy dissipation that occurs in such stacked manholes during diverse inflow conditions. Flow regimes inside the structure were identified and the effectiveness of the design was assessed under variable inflow conditions. Total energy dissipation in the stacked manhole was found to range from about 50% to 90%, and the contribution of each manhole chamber to the overall energy dissipation was assessed. A relationship between water depths in the manhole chambers and the corresponding outflow conditions was established. In addition, an analysis of the flow patterns and flow regimes highlighted the relevant parameters involved in the mechanisms of energy dissipation.

scholarly journals Bounding of Flow and Transport Analysis in Heterogeneous Saturated Porous Media: A Minimum Energy Dissipation Principle for the Bounding and Scale-Up

Hydrology ◽  
2019 ◽  
Vol 6 (2) ◽  
pp. 33 ◽  
Author(s):  
Nelson ◽  
Williams
Keyword(s):  
Porous Media ◽  
Energy Dissipation ◽  
Heterogeneous System ◽  
Minimum Energy ◽  
Scale Up ◽  
Heterogeneous Porous Media ◽  
Porous Media Flow ◽  
Rotational Flow ◽  
Energy Principles

We apply minimum kinetic energy principles from classic mechanics to heterogeneous porous media flow equations to derive and evaluate rotational flow components to determine bounding homogenous representations. Kelvin characterized irrotational motions in terms of energy dissipation and showed that minimum dynamic energy dissipation occurs if the motion is irrotational; i.e., a homogeneous flow system. For porous media flow, reductions in rotational flow represent heterogeneity reductions. At the limit, a homogeneous system, flow is irrotational. Using these principles, we can find a homogenous system that bounds a more complex heterogeneous system. We present mathematics for using the minimum energy principle to describe flow in heterogeneous porous media along with reduced special cases with the necessary bounding and associated scale-up equations. The first, simple derivation involves no boundary differences and gives results based on direct Kelvin-type minimum energy principles. It provides bounding criteria, but yields only a single ultimate scale-up. We present an extended derivation that considers differing boundaries, which may occur between scale-up elements. This approach enables a piecewise less heterogeneous representation to bound the more heterogeneous system. It provides scale-up flexibility for individual model elements with differing sizes, and shapes and supports a more accurate representation of material properties. We include a case study to illustrate bounding with a single direct scale-up. The case study demonstrates rigorous bounding and provides insight on using bounding flow to help understand heterogeneous systems. This work provides a theoretical basis for developing bounding models of flow systems. This provides a means to justify bounding conditions and results.

Viscous Dampers Utilized at an Operating Electronic Facility for Reducing Seismic Risk

2014 ◽  
Vol 1021 ◽  
pp. 128-139
Author(s):  
Heng Sheng Chang ◽  
Ji Ping Ge
Keyword(s):  
Energy Dissipation ◽  
Seismic Activity ◽  
Seismic Risk ◽  
Semiconductor Manufacturing ◽  
Damping Ratio ◽  
Viscous Damper ◽  
Fundamental Vibration ◽  
Passive Energy Dissipation ◽  
Energy Dissipation Devices

Using supplemental energy dissipation devices into the structure to increase the damping ratio for reducing the responses of seismic activity has become more and more popular. This paper presents a case study of seismic retrofit strategy, utilizing a type of passive energy dissipation device, namely, the viscous damper, in order to make an ongoing chips produced facility resistant to seismic activity. The building in question was a chips produced facility belonging to a semiconductor manufacturing company. This was a double FAB where the structure system was divided into an island building and an RC shell. The retrofit involved installing 44 non-linear dampers between the island building and the RC shell. This was due to the significant differences in the fundamental vibration periods. This paper will present the rationale of making a decision on the parameters of the dampers to give the optimum retrofit strategy.

scholarly journals Energy dissipation evaluation of temperature swing adsorption (TSA) cycle based on thermodynamic entropy insights

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Shuangjun Li ◽  
Shuai Deng ◽  
Li Zhao ◽  
Weicong Xu ◽  
Xiangzhou Yuan ◽  
...  
Keyword(s):  
Energy Dissipation ◽  
Entropy Generation ◽  
Heat Recovery ◽  
Internal Heat ◽  
Thermodynamic Cycle ◽  
Intergovernmental Panel ◽  
Thermodynamic Entropy ◽  
Temperature Swing ◽  
Temperature Swing Adsorption

Abstract The special report of the Intergovernmental Panel on Climate Change’s (IPCC) on global warming of 1.5 °C marks a critical point in climate negotiations, which emphasizes the importance to control the CO2 level in the atmosphere. The current technology cluster of CO2 capture is still energy-intensive which results in a substantial increase in costs, thus the efficient conversion among various forms of energy is the major topic of research. Considering that most of the existing research are primarily based on the viewpoint of energy conservation on a specific case study, the results thus could not be efficiently generalized as a condensed mechanism of energy dissipation. In this work, the entropy generation evaluation of a 4-step temperature swing adsorption (TSA) process was presented as a sample. The values and contribution distributions of various entropy generation in the thermodynamic cycle were calculated to evaluate the major energy dissipation. The results on contribution distribution of entropy generation and heat required were compared, the entropy generation distribution contributed by heat transfer decreases from 63.27% to 53.72% with internal heat recovery (IHR) method integrated. Thus the entropy generation saving potential of IHR method could be proved.

scholarly journals Analysis of the influence hybrid mass coordinate on WRF-ARW models to the turbulence simulation of Batik airlines aviation (case study October 24, 2017)

2021 ◽  
Vol 893 (1) ◽  
pp. 012032
Author(s):  
N A A Halimy ◽  
N J Trilaksono
Keyword(s):  
Energy Dissipation ◽  
Dissipation Rate ◽  
Richardson Number ◽  
Satellite Image ◽  
Image Data ◽  
Energy Dissipation Rate ◽  
Atmospheric Conditions ◽  
Turbulence Simulation ◽  
Satellite Image Data

Abstract The influence of hybrid sigma coordinate is better to represent turbulence in America than basic sigma coordinate. Therefore, it is necessary to search the effect of these coordinates on turbulence simulations in Indonesia due to the analysis of different atmospheric conditions from America. In this research, two experiments are performed using two different vertical coordinates with a case study flight turbulence from Batik Airlines on October 24, 2017. The two different vertical coordinates are the hybrid sigma coordinate and basic sigma coordinate. The data used are NCEP-FNL, Himawari-8 satellite image data, and sounding data. Based on the result of this research, simulation using hybrid sigma coordinate shows isentropic lines that have the potential turbulence during and after turbulence event. Richardson number value about 0.1 – 0.2 and intensity of the energy dissipation rate is 0.06 m 2/3s-1. According to the Richardson number value and intensity of the energy dissipation rate, the hybrid sigma coordinate simulation shows turbulence potential more significant than the basic sigma coordinate.

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