Model number

Water cooling by evaporation from an earthenware jug


Botijo fig 1
Model is from the paper by J.I. Zubizarreta and G. Pinto (see references).

This model provides a "quantitative explanation of an ancient method
of chilling water."  Earthenware pitchers with a spout and handel
(botijo in Spanish) have been used to hold and chill drinking water.
The slightly porous, clay-based pot allows water to transfer
through the wall of the pitcher and evaporate into the ambient 
environment.  The energy needed for evaporation (i.e., latent heat
of vaporization) is balanced by a reduction in the internal 
energy of the liquid inside the botijo.

Zubizarreta, J.I.  and Pinto, G. An Ancient method for cooling 
water explained by mass and heat transfer. Chem. Eng. Educ. 1995, 29, 96.


The equations for this model may be viewed by running the JSim model applet and clicking on the Source tab at the bottom left of JSim's Run Time graphical user interface. The equations are written in JSim's Mathematical Modeling Language (MML). See the Introduction to MML and the MML Reference Manual. Additional documentation for MML can be found by using the search option at the Physiome home page.

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Please cite in any publication for which this software is used and send one reprint to the address given below:
The National Simulation Resource, Director J. B. Bassingthwaighte, Department of Bioengineering, University of Washington, Seattle WA 98195-5061.

Model development and archiving support at provided by the following grants: NIH U01HL122199 Analyzing the Cardiac Power Grid, 09/15/2015 - 05/31/2020, NIH/NIBIB BE08407 Software Integration, JSim and SBW 6/1/09-5/31/13; NIH/NHLBI T15 HL88516-01 Modeling for Heart, Lung and Blood: From Cell to Organ, 4/1/07-3/31/11; NSF BES-0506477 Adaptive Multi-Scale Model Simulation, 8/15/05-7/31/08; NIH/NHLBI R01 HL073598 Core 3: 3D Imaging and Computer Modeling of the Respiratory Tract, 9/1/04-8/31/09; as well as prior support from NIH/NCRR P41 RR01243 Simulation Resource in Circulatory Mass Transport and Exchange, 12/1/1980-11/30/01 and NIH/NIBIB R01 EB001973 JSim: A Simulation Analysis Platform, 3/1/02-2/28/07.