4,722 research outputs found
Thermal diffusion segregation of an impurity in a driven granular fluid
We study segregation of an impurity in a driven granular fluid under two
types of \emph{steady} states. In the first state, the granular gas is driven
by a stochastic volume force field with a Fourier-type profile while in the
second state, the granular gas is sheared in such a way that inelastic cooling
is balanced by viscous heating. We compare theoretical results derived from a
solution of the (inelastic) Boltzmann equation at Navier-Stokes (NS) order with
those obtained from the Direct Monte Carlo simulation (DSMC) method and
molecular dynamics (MD) simulations. Good agreement is found between theory and
simulation, which provides strong evidence of the reliability of NS granular
hydrodynamics for these steady states (including the dynamics of the impurity),
even at high inelasticities. In addition, preliminary results for thermal
diffusion in granular fluids at moderate densitis are also presented. As for
dilute gases \cite{VGK14}, excellent agreement is also found in this more
general case.Comment: 6 pages; 4 figures; contributed paper at the 29th International
Symposium on Rarefied Gas Dynamics (Xi'an, China, July 13-18th, 2012); 29th
International Symposium on Rarefied Gas Dynamics 201
Choice Experiments in Enviromental Impact Assessment: The Toro 3 Hydroelectric Project and the Recreo Verde Tourist Center in Costa Rica
Choice experiments, a stated preference valuation method, are proposed as a tool to assign monetary values to environmental externalities during the ex-ante stages of environmental impact assessment. This case study looks at the impacts of the Costa Rican Institute of Electricity’s Toro 3 hydroelectric project and its affects on the Recreo Verde tourism center in San Carlos, Costa Rica. Compared to other valuation methods (e.g., travel cost and contingent valuation), choice experiments can create hypothetical but realistic scenarios for consumers and generate restoration alternatives for the affected good. Although they have limitations that must be taken into account in environmental impact assessments, incorporating economic parameters—especially resource constraints and tradeoffs—can substantially enrich the assessment process.stated-preference, economic valuation, choice experiments, hydropower, tourism, Costa Rica
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