Abstract
Abstract
A subsurface porous pipe irrigation system has been widely used, water seeps from the porous pipe into the soil. Such systems can carry out both conveyance and seepage in the same time. Hence by this research, it is investigated the effect of saturated hydraulic conductivity of the porous pipe on the movement of soil moisture contents by using five values of 0.05, 0.075, 0.1, 0.125, and 0.15 cm/hr for the pipe. The pipe is installed at a depth of 15 cm with 6 cm as the outer diameter. Then water heads of 25, 50, and 75 cm are applied for 2 hours as an operation time. Preparations in the HYDRUS/2D are done and all movements of soil moisture contents are recorded with time. Empirical functions are found with the collected data in both sides of horizontal and vertical directions with an average relative error value not exceeds 4 % and with coefficients of determination more than 0.97. Therefore, these empirical functions are well fitted and can be used as an indicator in designing system of subsurface porous pipe irrigation.