Peter Chew Triangle Diagram and Application

2021 ◽  
Author(s):  
Peter Chew
Keyword(s):  
Triangle Diagram

scholarly journals Trade-off between reservoir yield and evaporation losses as a function of lake morphology in semi-arid Brazil

2016 ◽  
Vol 88 (2) ◽  
pp. 1113-1125 ◽  
Author(s):  
José N.B. Campos ◽  
Iran E. Lima Neto ◽  
Ticiana M.C. Studart ◽  
Luiz S.V. Nascimento
Keyword(s):  
Water Yield ◽  
Prediction Errors ◽  
Arid Environments ◽  
Triangle Diagram ◽  
Trade Off ◽  
The Real ◽  
Lake Morphology ◽  
Evaporation Losses ◽  
Semi Arid ◽  
Reservoir Yield

This study investigates the relationships between yield and evaporation as a function of lake morphology in semi-arid Brazil. First, a new methodology was proposed to classify the morphology of 40 reservoirs in the Ceará State, with storage capacities ranging from approximately 5 to 4500 hm3. Then, Monte Carlo simulations were conducted to study the effect of reservoir morphology (including real and simplified conical forms) on the water storage process at different reliability levels. The reservoirs were categorized as convex (60.0%), slightly convex (27.5%) or linear (12.5%). When the conical approximation was used instead of the real lake form, a trade-off occurred between reservoir yield and evaporation losses, with different trends for the convex, slightly convex and linear reservoirs. Using the conical approximation, the water yield prediction errors reached approximately 5% of the mean annual inflow, which is negligible for large reservoirs. However, for smaller reservoirs, this error became important. Therefore, this paper presents a new procedure for correcting the yield-evaporation relationships that were obtained by assuming a conical approximation rather than the real reservoir morphology. The combination of this correction with the Regulation Triangle Diagram is useful for rapidly and objectively predicting reservoir yield and evaporation losses in semi-arid environments.

scholarly journals PRELIMINARY DESIGN OF RDE FEEDWATER PUMP IMPELLER

2018 ◽  
Vol 20 (1) ◽  
pp. 1 ◽  
Author(s):  
Sri Sudadiyo
Keyword(s):  
Nuclear Power ◽  
Power Plants ◽  
Nuclear Reactor ◽  
Thermal Power ◽  
Performance Characteristics ◽  
Preliminary Design ◽  
Triangle Diagram ◽  
Pump Impeller ◽  
Impeller Blade ◽  
Feedwater Pump

Nowadays, pumps are being widely used in the thermal power generation including nuclear power plants. Reaktor Daya Eksperimental (RDE) is a proposed nuclear reactor concept for the type of nuclear power plant in Indonesia. This RDE has thermal power 10 MWth, and uses a feedwater pump within its steam cycle. The performance of feedwater pump depends on size and geometry of impeller model, such as the number of blades and the blade angle. The purpose of this study is to perform a preliminary design on an impeller of feedwater pump for RDE and to simulate its performance characteristics. The Fortran code is used as an aid in data calculation in order to rapidly compute the blade shape of feedwater pump impeller, particularly for a RDE case. The calculations analyses is solved by utilizing empirical correlations, which are related to size and geometry of a pump impeller model, while performance characteristics analysis is done based on velocity triangle diagram. The effect of leakage, pass through the impeller due to the required clearances between the feedwater pump impeller and the volute channel, is also considered. Comparison between the feedwater pump of HTR-10 and of RDE shows similarity in the trend line of curve shape. These characteristics curves will be very useful for the values prediction of performance of a RDE feedwater pump. Preliminary design of feedwater pump provides the size and geometry of impeller blade model with 5-blades, inlet angle 14.5 degrees, exit angle 25 degrees, inside diameter 81.3 mm, exit diameter 275.2 mm, thickness 4.7 mm, and height 14.1 mm. In addition, the optimal values of performance characteristics were obtained when flow capacity was 4.8 kg/s, fluid head was 29.1 m, shaft mechanical power was 2.64 kW, and efficiency was 52 % at rotational speed 1750 rpm.Keywords: Blade, impeller, pump, RDEDESAIN AWAL IMPELER POMPA AIR UMPAN RDE. Saat ini, pompa digunakan secara luas dalam pembangkit tenaga termal termasuk pembangkit listrik tenaga nuklir. Reaktor Daya Eksperimental (RDE) merupakan konsep reaktor nuklir yang diusulkan untuk tipe PLTN di Indonesia. RDE ini memiliki daya termal 10 MWth, dan menggunakan pompa air umpan dalam siklus uapnya. Kinerja pompa air umpan bergantung pada ukuran dan geometri model impeller, seperti jumlah sudu dan sudut sudu. Tujuan dari penelitian ini adalah untuk membuat rancangan awal impeller pompa air umpan untuk RDE dan untuk mensimulasikan karakteristik kinerjanya. Kode Fortran digunakan sebagai bantuan dalam penghitungan data untuk untuk mengkalkulasi secara cepat bentuk sudu impeller pompa air umpan, terutama pada kasus RDE. Analisis perhitungan dipecahkan menggunakan korelasi empiris yang terkait dengan ukuran dan geometri model impeller pompa, sedangkan analisis karakteristik kinerja dilakukan berdasarkan diagram segitiga kecepatan. Pengaruh bocoran, melalui impeler akibat celah yang diperlukan antara impeller pompa air umpan dan saluran volute, juga dipertimbangkan. Perbandingan antara pompa air umpan HTR-10 dan RDE menunjukkan kemiripan dalam garis tren bentuk kurva. Kurva karakteristik ini akan sangat berguna untuk perkiraan nilai kinerja pompa air umpan RDE. Desain awal pompa air umpan memberikan ukuran dan geometri model sudu impeller dengan 5-sudu, sudut masuk 14,5 derajat, sudut keluar 25 derajat, diameter dalam 81,3 mm, diameter luar 275,2 mm, ketebalan 4,7 mm, dan tinggi 14,1 mm. Selain itu, nilai optimal karakteristik kinerja diperoleh ketika kapasitas aliran 4,8 kg/s, head fluida 29,1 m, tenaga mekanik poros 2,64 kW, dan efisiensi 52 % pada kecepatan putaran 1750 rpm.Kata kunci: Sudu, impeler, pompa, RDE

scholarly journals FORM FACTORS IN B → f0(980) AND D → f0(980) TRANSITIONS FROM DISPERSION RELATIONS

2007 ◽  
Vol 22 (02n03) ◽  
pp. 641-644 ◽  
Author(s):  
B. El-BENNICH ◽  
O. M. A. LEITNER ◽  
B. LOISEAU ◽  
J. P. DEDONDER
Keyword(s):  
Dispersion Relation ◽  
Spectral Representation ◽  
Form Factors ◽  
Dispersion Relations ◽  
Transition Form ◽  
Spectral Densities ◽  
Triangle Diagram ◽  
Relation Approach

Within the dispersion relation approach we give the double spectral representation for space-like and time-like B → f0(980) and D → f0(980) transition form factors in the whole q2 range. The spectral densities, being the input of the dispersion relations, are obtained from a triangle diagram of relativistic constituent quarks.

scholarly journals MODELING ATMOSPHERE COMPOSITION AND DETERMINING EXPLOSIBILITY IN A SEALED COAL MINE VOLUME

2014 ◽  
Vol 59 (1) ◽  
pp. 25-40 ◽  
Author(s):  
Jianwei Cheng ◽  
Yi Luo
Keyword(s):  
Mathematical Model ◽  
Control Volume ◽  
Inert Gases ◽  
Mine Safety ◽  
Air Leakage ◽  
Gas Explosion ◽  
Triangle Diagram ◽  
Underground Coal Mines ◽  
Control Volume Approach ◽  
Explosion Risk

Abstract Explosions originated from or around the sealed areas in underground coal mines present a serious safety threat. The explosibility of the mine atmosphere depends on the composition of oxygen, combustible and inert gases. In additional, the composition in the inaccessible sealed areas change with time under various factors, such as gases emissions, air leakage, inert gases injected, etc. In order to improve mine safety, in this paper, a mathematical model based on the control volume approach to simulate the atmosphere compositions is developed, and the expanded Coward explosibility triangle diagram is used to assess the mine gas explosion risk. A computer program is developed to carry out the required computations and to display the results. In addition, the USBM explosibility diagram is also included in the program to serve as a double check.

scholarly journals Mass Spectra and Decay of Mesons under Strong External Magnetic Field

2021 ◽  
Author(s):  
Shuyun Yang ◽  
Meng Jin ◽  
DeFu Hou
Keyword(s):  
Magnetic Field ◽  
External Magnetic Field ◽  
Mass Spectra ◽  
Chemical Potential ◽  
Energy Gap ◽  
Random Phase ◽  
High Energy ◽  
Decay Process ◽  
Triangle Diagram ◽  
Magnetic Catalysis

Abstract We study the mass spectra and decay process of σ and π0 mesons under strong external magnetic field. To achieve this goal, we deduce the thermodynamic potential in a two-flavor, hot and magnetized Nambu-Jona-Lasinio model. We calculate the energy gap equation through the random phase approximation (RPA). Then we use Ritus method to calculate the decay triangle diagram and self-energy in the presence of a constant magnetic field B. Our results indicate that the magnetic field has little influence on the mass of π0 at low temperatures. While for quarks and σ mesons, their mass changes obviously, which reflects the influence of magnetic catalysis (MC). The presence of magnetic field accelerates the decay of the meson while the presence of chemical potential will decrease the decay process. Content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. Article funded by SCOAP3 and published under licence by Chinese Physical Society and the Institute of High Energy Physics of the Chinese Academy of Science and the Institute of Modern Physics of the Chinese Academy of Sciences and IOP Publishing Ltd.

scholarly journals Landau diagrams in AdS and S-matrices from conformal correlators

2020 ◽  
Vol 2020 (11) ◽  
Author(s):  
Shota Komatsu ◽  
Miguel F. Paulos ◽  
Balt C. van Rees ◽  
Xiang Zhao
Keyword(s):  
Flat Space ◽  
Momentum Conservation ◽  
Quantum Field Theories ◽  
Triangle Diagram ◽  
S Matrix ◽  
Space Limit ◽  
Anomalous Threshold ◽  
Delta Functions ◽  
Shell Particles ◽  
Do So

Abstract Quantum field theories in AdS generate conformal correlation functions on the boundary, and in the limit where AdS is nearly flat one should be able to extract an S-matrix from such correlators. We discuss a particularly simple position-space procedure to do so. It features a direct map from boundary positions to (on-shell) momenta and thereby relates cross ratios to Mandelstam invariants. This recipe succeeds in several examples, includes the momentum-conserving delta functions, and can be shown to imply the two proposals in [1] based on Mellin space and on the OPE data. Interestingly the procedure does not always work: the Landau singularities of a Feynman diagram are shown to be part of larger regions, to be called ‘bad regions’, where the flat-space limit of the Witten diagram diverges. To capture these divergences we introduce the notion of Landau diagrams in AdS. As in flat space, these describe on-shell particles propagating over large distances in a complexified space, with a form of momentum conservation holding at each bulk vertex. As an application we recover the anomalous threshold of the four-point triangle diagram at the boundary of a bad region.

scholarly journals The Temperature Evaluation of the Buried Hill Geothermal Reservoirs in the Jizhong Depression, Bohai Bay Basin, China

Geofluids ◽  
2020 ◽  
Vol 2020 ◽  
pp. 1-14
Author(s):  
Yuyang Dong ◽  
Jianhui Zeng ◽  
Xianzheng Zhao ◽  
Yanu Wang ◽  
Tianhao Chen ◽  
...  
Keyword(s):  
Geothermal Water ◽  
Bohai Bay ◽  
Bohai Bay Basin ◽  
Triangle Diagram ◽  
Group Iii ◽  
Geothermal Reservoirs ◽  
Jizhong Depression ◽  
Shallow Strata ◽  
Deep Strata ◽  
Buried Hill

The Jizhong Depression is located in the western Bohai Bay Basin, eastern China. The deep strata are mainly composed of carbonate buried hill, and the shallow strata are a mainly siliciclastic deposition. In the present work, the Na-K-Mg triangle diagram and geothermometers were used to investigate the geochemical characteristics of shallow groundwater and reservoir temperature features of three geothermal reservoirs in the depression, including the Ordovician, the Cambrian, and the Precambrian Wumishan Formation. The results showed that the geothermal water in the depression could be divided into three groups: group I, Cl· HCO 3 -Na type; group II, Cl-Na type; and group III, Cl-Na·Ca type. By using the Na-K-Mg triangle diagram, group II and group III geothermal water samples were identified as the partially equilibrated water, whose temperature of the geothermal reservoir can be calculated based on the cation geothermometers. The ranges of the calculated temperature of the shallow strata and the deep strata are 91~146°C and 147~176°C, respectively. It has the good results obtained with some cation geothermometers in a geothermal system hosted in carbonate rocks like the studied area. The analysis workflow and calculation data obtained in this work contribute to the evaluation of the temperature field and the exploration and development of the geothermal resources in the Bohai Bay Basin.

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