Determination of the transition curve between flow modes during filtering an acid through a chemically active porous medium

It is known that during the filtration flow, if the displacing liquid can chemically react with the skeleton while emitting a gas phase, then this flow mode may be unstable. During the filtration process, pressure fluctuations will be observed, and the displacing fluid will move in waves called “acid waves”. Our research suggests a simple theoretical model that gives a qualitative explanation of the causes of this phenomenon. We conducted laboratory simulations and detected the boundary of the appearance of “acid waves”, depending on the concentration of the chemically active component. At the same time the theoretical model can also predict the appearance of “acid waves” in the laboratory experiment, which will allow scaling the studied phenomenon in the future.

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Absolute determination of the differential elastic cross section and total inelastic cross sections for the collision He+-He between 3 and 50 keV and between 0.25 and 3 degrees. Elaboration of a simple theoretical model

Journal of Physics B Atomic and Molecular Physics ◽

10.1088/0022-3700/16/11/015 ◽

1983 ◽

Vol 16 (11) ◽

pp. 1937-1955

Author(s):

D Bordenave-Montesquieu ◽

A Boutonnet ◽

C Bergnes ◽

R Dagnac

Keyword(s):

Theoretical Model ◽

Cross Section ◽

Cross Sections ◽

Elastic Cross Section ◽

Absolute Determination ◽

Simple Theoretical Model

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On stability boundary of the flow of an acid solution through a chemically active porous medium

Journal of Physics Conference Series ◽

10.1088/1742-6596/2090/1/012029 ◽

2021 ◽

Vol 2090 (1) ◽

pp. 012029

Author(s):

Rinat Plavnik ◽

Ivan Zavialov ◽

Andrey Konyukhov ◽

Oleg Izvekov ◽

Sergey Negodyaev

Keyword(s):

Porous Medium ◽

Gas Phase ◽

Stability Boundary ◽

Pressure Fluctuations ◽

Qualitative Explanation ◽

Laboratory Modeling ◽

Active Components ◽

Proposed Model ◽

Process Pressure ◽

The Waves

Abstract It is known that during the flow, if the displacing fluid can chemically react with the components of porous medium and with the release of a gas phase, then such a flow regime can be unstable. During this process, pressure fluctuations can be observed, and the displacing fluid will move in “waves”. In the course of our research, a simple mathematical model was proposed that provides a qualitative explanation of the reasons for the emergence of such a phenomenon; laboratory modeling was carried out, and the criterion of the “waves” formation was found, depending on the concentration of chemically active components. The proposed model can predict the emergence of the wave instabilities in a laboratory experiment, which will allow to carry out a future experiment on a larger scale.

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Incumbent and Entrant Bidding in Scoring Rule Auctions: A Study on Italian Canteen Services

The B E Journal of Economic Analysis & Policy ◽

10.1515/bejeap-2019-0146 ◽

2020 ◽

Vol 0 (0) ◽

Author(s):

Riccardo Camboni ◽

Paola Valbonesi

Keyword(s):

Theoretical Model ◽

Production Cost ◽

Specific Information ◽

Scoring Rule ◽

The Public ◽

Simple Theoretical Model ◽

Original Dataset

AbstractWe empirically investigate incumbents’ and entrants’ bids on an original dataset of 192 scoring rule auctions for canteen services in Italy. Our findings show that winning rebates are lower (i.e., prices paid by the public buyer are higher) when the contract is awarded to the incumbent supplier. This result is not explained by the observable characteristics of the auction or the service awarded. We develop a simple theoretical model showing that the result is consistent with a setting in which the buyer exploits specific information on the incumbent supplier’s production cost.

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Market Choices Driven by Reference Groups: A Comparison of Analytical and Simulation Results on Random Networks

Entropy ◽

10.3390/e23081007 ◽

2021 ◽

Vol 23 (8) ◽

pp. 1007

Author(s):

Michał Ramsza

Keyword(s):

Theoretical Model ◽

Reference Group ◽

Third Party ◽

Qualitative Behavior ◽

Reference Groups ◽

Group Influence ◽

Simple Theoretical Model ◽

High Connectivity ◽

Simulation Results ◽

Two Equilibria

The present paper reports simulation results for a simple model of reference group influence on market choices, e.g., brand selection. The model was simulated on three types of random graphs, Erdos–Renyi, Barabasi–Albert, and Watts–Strogatz. The estimates of equilibria based on the simulation results were compared to the equilibria of the theoretical model. It was verified that the simulations exhibited the same qualitative behavior as the theoretical model, and for graphs with high connectivity and low clustering, the quantitative predictions offered a viable approximation. These results allowed extending the results from the simple theoretical model to networks. Thus, by increasing the positive response towards the reference group, the third party may create a bistable situation with two equilibria at which respective brands dominate the market. This task is easier for large reference groups.

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