scholarly journals Unsteady compressible flow in ducts with varying cross-section: Comparison between the nonconservative Euler system and the axisymmetric flow model

2012 ◽  
Vol 53 ◽  
pp. 53-78 ◽  
Author(s):  
D. Rochette ◽  
S. Clain ◽  
W. Bussière
Keyword(s):  
Compressible Flow ◽  
Cross Section ◽  
Flow Model ◽  
Axisymmetric Flow ◽  
Euler System

Cross Section of KOSPI Returns Based on Cash Flow Risk Factors

2018 ◽  
Vol 26 (3) ◽  
pp. 311-343
Author(s):  
Sungjeh Moon ◽  
Joonhyuk Song
Keyword(s):  
Risk Factors ◽  
Cross Section ◽  
Cash Flow ◽  
Risk Premium ◽  
Flow Model ◽  
Equity Risk Premium ◽  
Consumption Growth ◽  
Equity Risk ◽  
Long Run ◽  
Pricing Error

This paper introduces two risk factors which are the covariance between long-run consumption growth and cash flows and the duration of cash flow, and investigates how these factors serve to explain the KOSPI return risk premiums. Based on our empirical results comparing the proposed two-factor cash flow model with the standard benchmark models such as CAPM and Fama-French 3-factor model (FF-3F), using KOSPI equity including de-listed stocks, the cash flow model explains 74.7% of the cross-section of equity risk premium while CAPM and FF-3F model explains 41.9% and 64.1% to the maximum, respectively, showing that the cash-flow model is superior in explaining the risk premium factor structure compared with the benchmark models. Also, the pricing error is only 4% in the two-factor cash flow model, while CAPM and FF-3F are 7.7% and 4.7%, respectively, indicating the cash flow model outperforms the standard benchmark models in pricing error as well. These results can be interpreted that the cross section of the equity risk premium is related to a firm’s cash flow and long-run consumption, and therefore the growth rate of consumption in the long run rather than contemporaneous consumption growth rate has a greater influence on the determination of the risk premium.

Optimization of Groove-Hole Distribution with Equidistant and Unequal Diameter on Air-Cushion Belt Conveyor

2008 ◽  
Vol 44-46 ◽  
pp. 635-642
Author(s):  
J.F. Li ◽  
Suo Long Zhang
Keyword(s):  
Numerical Simulation ◽  
Flow Field ◽  
Research And Development ◽  
Cross Section ◽  
Flow Model ◽  
Optimal Parameters ◽  
Belt Conveyor ◽  
Air Cushion ◽  
Fluent Software ◽  
Air Hole

In this paper, the research and development of the distribution of air-holes in the groove of air-cushion belt conveyor were introduced. The expressions of air-cushion pressure were given and the graph of it was shown as well. The air flow model nearby groove-holes and air outflow model on cross section were given too. In the same time, the distributing mode of equidistant air-holes with unequal diameter was studied and analyzed. In order to make up the shortage of the study on air-hole distributing mode of equidistant air-holes with unequal diameter on the air-cushion belt conveyor, an instance of the air-cushion flow field was numerically simulated based on the CFD software ,Fluent software. Several groups of data of different air-hole distributions, (for example, the center distances of air-holes in the groove of air-cushion belt conveyor are the same as each other and their diameters are different), were selected to compare with each other , and then, the results were compared with existing theory. According to the different results of the numerical simulation on the distributing mode of equidistant air-holes with unequal diameter, the optimal parameters of air-hole distributing mode were obtained, and the effect of prevent offset that comes the balance groove-hole on air-cushion belt conveyor. Moreover, the verification to prove the agreement between the results of numerically simulated and basic theory was carried out by the comparison analyses. The theoretical feasibility of air-hole distributing mode of equidistant air-holes with unequal diameter was analyzed.

Numerical study on annular tube once-through steam generator using compressible flow model

2012 ◽  
Vol 39 (1) ◽  
pp. 49-55 ◽  
Author(s):  
Z.L. Wang ◽  
W.X. Tian ◽  
Y.W. Wu ◽  
S.Z. Qiu ◽  
G.H. Su
Keyword(s):  
Compressible Flow ◽  
Steam Generator ◽  
Flow Model ◽  
Numerical Study ◽  
Annular Tube

Nonuniform Flow in a Compressor Due to Asymmetric Tip Clearance

2000 ◽  
Vol 122 (4) ◽  
pp. 751-760 ◽  
Author(s):  
Seung Jin Song ◽  
Seung Ho Cho
Keyword(s):  
Analytical Study ◽  
Flow Model ◽  
Axisymmetric Flow ◽  
Tip Clearance ◽  
Linear Perturbation ◽  
Flow Variable ◽  
Nonuniform Flow ◽  
Downstream Flow ◽  
Perturbation Approximation ◽  
Flow Nonuniformity

This paper presents an analytical study of flow redistribution in a compressor stage due to asymmetric tip clearance distribution. The entire stage is modeled as an actuator disk and it is assumed that upstream and downstream flow fields are determined by the local tip clearance. The flow is assumed to be inviscid and incompressible. First, an axisymmetric flow model is used to connect upstream and downstream flows. Second, a linear perturbation approximation is used for nonaxisymmetric analysis in which each flow variable is assumed to consist of a mean (axisymmetric value) plus a small perturbation (asymmetric value). Thus, the perturbations in velocity and pressure induced by the tip clearance asymmetry are predicted. Furthermore, rotordynamic effects of such flow nonuniformity are examined as well. [S0889-504X(00)01404-5]

Measurements of Blowdown Thrust Loading in Natural Gas Facilities

2019 ◽  
Vol 141 (6) ◽  
Author(s):  
K. K. Botros ◽  
H. Charette ◽  
M. Martens ◽  
M. Beckel ◽  
G. Szuch
Keyword(s):  
Experimental Data ◽  
Natural Gas ◽  
Compressible Flow ◽  
Gas Flow ◽  
Flow Model ◽  
Stagnation Pressure ◽  
Flow Meters ◽  
One Dimensional ◽  
Pressure Losses ◽  
Modeling Approach

Abstract The thrust loading on a vertical blowdown stack during a natural gas blowdown was investigated using a combined experimental and modeling approach. A gravimetric vessel initially at 4000 kPa-g was blown down through two geometrically different stack assemblies. Thrust loads were measured using a dynamic weigh scale typically used for gravimetric calibration of gas flow meters. A one-dimensional (1D) compressible flow model, calibrated using the experimental data, revealed stagnation pressure losses at the entrance to the riser, resulting in lower thrust loads. A comparison between thrust loading obtained from the measurements and the 1D compressible flow model is presented. This work shows that the analytical flow model predicts the blowdown thrust loads within ±30%.

Micro‐flow model with a new algorithm of random fiber distribution over the transverse cross‐section

2020 ◽  
Vol 41 (12) ◽  
pp. 5006-5015
Author(s):  
Junling Liu ◽  
Li Chen ◽  
Junbo Xie ◽  
Ziyuan Lin
Keyword(s):  
Cross Section ◽  
Flow Model ◽  
Transverse Cross Section ◽  
Fiber Distribution ◽  
Micro Flow

Continuous Production of Biodiesel with Supercritical Methanol: a Simple Compressible Flow Model for Tubular ReactorsRuengwit Sawangkeaw, Chulalongkorn University. Witsanee Satayanon, Chulalongkorn University. Kunchana Bunyakiat, Chulalongkorn University. Séverine Camy, University of Toulouse, Institut National Polytechnique de Toulouse, France. Jean-Stéphane Condoret, University of Toulouse, Institut National Polytechnique de Toulouse, France. Somkiat Ngamprasertsith, Fuels Research Center, Department of Chemical Technology, Faculty of Science, Chulalongkorn University, Bangkok, 10330, Thailand and Center for Petroleum, Petrochemicals and Advance Materials, Chulalongkorn University, Bangkok, 10330, Thailand. Please send correspondence to Somkiat Ngamprasertsith, [email protected]. We express our sincere appreciation to Chulalongkorn University Dutsadi Phiphat Scholarship, the Center for Petroleum, Petrochemicals and Advanced Materials and the Thai Government Stimulus Package 2 (TKK2555), under the Project for Establishment of Comprehensive Center for Innovative Food, Health Products and Agriculture, for financial support. The authors also wish to express their thankfulness to Dr. Robert Douglas John Butcher (Publication Counseling Unit, Faculty of Science, Chulalongkorn University) for English language editing.

ENERGYO ◽  
2018 ◽  
Author(s):  
Ruengwit Sawangkeaw ◽  
Séverine Camy ◽  
Witsanee Satayanon ◽  
Jean-Stéphane Condoret ◽  
Kunchana Bunyakiat ◽  
...  
Keyword(s):  
Compressible Flow ◽  
Financial Support ◽  
English Language ◽  
Flow Model ◽  
Continuous Production ◽  
Advanced Materials ◽  
Supercritical Methanol ◽  
Health Products ◽  
Thai Government ◽  
Stimulus Package

Magnetohydrodynamic Vortex Containment, Part 3: 1-D Axisymmetric Flow Model

2007 ◽  
Vol 23 (2) ◽  
pp. 404-413
Author(s):  
Raymond J. Sedwick ◽  
Daniel A. Zayas
Keyword(s):  
Flow Model ◽  
Axisymmetric Flow
Sign in / Sign up

Export Citation Format

Share Document