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Title: Modelling Studies of the Evolution of Vapour-Dominated Geothermal Systems

Abstract

Numerical experiments, based on linear stability results, are invoked to model the evolution of two-phase vapor-dominated zones within geothermal systems. A reservoir model with all boundaries impermeable to fluid flow and a uniform heat flux at the bottom boundary is used. The results obtained show that different steady-states are accessible along different quasi-static paths from the same initial vapor-dominated steady-state. Thus, the realization of a steady-state with a two-phase vapor-dominated zone overlying a single-phase hot water region can indicate that the geothermal system undergoes a process of slow cooling. A steady-state with a two-phase vapor-dominated zone overlying a single-phase vapor region can be formed either as a result of slow heating or as a result of a reduction in permeability. A steady-state with an upper vapor-dominated part and a lower liquid-dominated part can occur if permeability of the system has been gradually increased.

Authors:
Publication Date:
Research Org.:
Mathematics Dept., Victoria University of Wellington, Wellington, NZ
Sponsoring Org.:
USDOE
OSTI Identifier:
895953
Report Number(s):
GEO-PROC-95-02
TRN: US200703%%766
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
15 GEOTHERMAL ENERGY; FLUID FLOW; GEOTHERMAL SYSTEMS; HEAT FLUX; HEATING; HOT WATER; PERMEABILITY; SIMULATION; STABILITY; Geothermal Legacy

Citation Formats

Pestov, I. Modelling Studies of the Evolution of Vapour-Dominated Geothermal Systems. United States: N. p., 1995. Web. doi:10.2172/895953.
Pestov, I. Modelling Studies of the Evolution of Vapour-Dominated Geothermal Systems. United States. doi:10.2172/895953.
Pestov, I. Sun . "Modelling Studies of the Evolution of Vapour-Dominated Geothermal Systems". United States. doi:10.2172/895953. https://www.osti.gov/servlets/purl/895953.
@article{osti_895953,
title = {Modelling Studies of the Evolution of Vapour-Dominated Geothermal Systems},
author = {Pestov, I.},
abstractNote = {Numerical experiments, based on linear stability results, are invoked to model the evolution of two-phase vapor-dominated zones within geothermal systems. A reservoir model with all boundaries impermeable to fluid flow and a uniform heat flux at the bottom boundary is used. The results obtained show that different steady-states are accessible along different quasi-static paths from the same initial vapor-dominated steady-state. Thus, the realization of a steady-state with a two-phase vapor-dominated zone overlying a single-phase hot water region can indicate that the geothermal system undergoes a process of slow cooling. A steady-state with a two-phase vapor-dominated zone overlying a single-phase vapor region can be formed either as a result of slow heating or as a result of a reduction in permeability. A steady-state with an upper vapor-dominated part and a lower liquid-dominated part can occur if permeability of the system has been gradually increased.},
doi = {10.2172/895953},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Sun Jan 01 00:00:00 EST 1995},
month = {Sun Jan 01 00:00:00 EST 1995}
}

Technical Report:

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