Evaporation

Potential Evaporation (Penman 1948)

Potential Evaporation, Penman 1948.

where:

PE = Potential Evaporation

G = slope of saturated vapor pressure (kPa/oC)

Qn = Net radiation (MJ/m2/day)

Ea = Energy (mm/day)

h = Psychimetric constant (kPa/oC)

Actual evaporation (modified Penman equation) incorporate potential evaporation and relative humidity of soil.

Actual Evaporation, Wilson et al 1997.

where:

Ratio of actual evaporation and potential evaporation versus total suction for different soils, Rahardjo et al 2013

Variations of soil and air temperatures for residual soil slope at Yishun, Singapore (Oct to Dec 98), Rahardjo et al 2013

Typical variation for differences of soil and air temperature for residual soil slope at Yishun, Rahardjo et al 2013

Setup of shrinkage test under accelerated evaporation using a lamp, Krisdani et al 2008

Evaporation pan, Rahardjo et al 2001

References

1. Rahardjo, H., Satyanaga, A., Leong, E. C. and Wang, J. Y. (2014). “Comprehensive instrumentation for real time monitoring of flux boundary conditions in slope.” Procedia Earth and Planetary Science, August, 9, 23-43.doi
2. Rahardjo, H., Satyanaga, A. and Leong, E. C. (2013). “Effects of flux boundary conditions on pore-water pressure distribution in slope.” Journal of Engineering Geology, Special Issue on Unsaturated Soils: Theory and Applications, October, 165, 133-142. doi | handle
3. Fredlund, D.G., Rahardjo, H. and Fredlund, M. D. (2012). Unsaturated soil mechanics in engineering practice, John Wiley & Sons, Inc., New York, 926 pages (ISBN 978-1-118-13359-0). e-book
4. Krisdani, H., Rahardjo, H. and Leong, E. C. (2008). “Effects of different drying rates on shrinkage characteristics of a residual soil and soil mixtures.”Engineering Geology, 102(1-2), 31-37. doi | handle
5. Rahardjo, H., Leong, E. C., Rezaur, R. B. (2001). “Assessment and instrumentation of slopes for stability against rainfall.” INVITED PANEL PRESENTATION in Session 6 “Specialty Session on Slope Engineering.”Proceedings of the 14th Southeast Asian Geotechnical Conference, Hong Kong, 10-14 December, Vol.1, 675–684.
6. Wilson, G.W., Fredlund, D.G., Barbour, S.L. (1997). “The effect of soil suction on evaporative fluxes from soil surfaces.” Canadian Geotechnical Journal, 34, 145–155. doi
7. Penman, H.L. (1948). “Natural evapotranspiration from open water, bare soil and grass.” Proceedings of the Royal Society of London Series A 193, 120–145.doi