Fitting Infiltration Equations using Double Ring Infiltrometer to Design and Evaluate Irrigation Methods

Abstract

In the present Outcome Based Education in Engineering, higher order skills in psychomotor domain are required as per Dave’s Taxonomy,Simpson’s Taxonomy and Anita Harrow’s Taxonomy.Not only computational skills are required but also experimental skills to develop the engineering skills life long. According to Walter J. Rawls et.al(1993), infiltration and soil water movement play a key role in surface runoff, groundwater recharge,evapotranspiration, soil erosion and transport of chemicals in surface and subsurface waters.The ASTM International Standard D 3385- 03 describes the “ Standard Test Method for Infiltration Rates of Soils in field using Double Ring Infiltrometer”. The present paper describes the methodology of development of Kostiakov Infiltration Equations from the field tests of Double Ring Infiltrometer,as part of various student projects of design and evaluation of irrigation methods. As properties of soil also influence the infiltration rate, soil properties are also determined. In one test, the Kostiakov infiltration equation fitted is in the form y=0.44t0.65. The basic infiltration rate is 44 millimeters/hour. Other methods of infiltration equations are briefly mentioned.\