The Drain Permeameter, "PPD", has been designed to measure the permeability of different filter materials when a fluid is passing through them, as well as to determine the most optimal combination of filter/soil.
The main element is a transparent column that can be filled with any type of soil and has a removable base where the filter material under study is placed. The unit includes as filter material three metal filters of different mesh size that can be interchanged in an easy and quick way.
Water is added to the column at constant pressure and the permeated water and soil are collected at the base, in a tank placed under the column. The discharge of the drain can be observed to evaluate the efficiency of the filter material.
To add water at constant pressure to the permeameter, water is raised by a pump from a feed tank to a water inlet tank that is connected to the upper part of the permeameter. This inlet tank has an overflow channel adjustable in height that discharges directly into the feed tank. In this way, all water that exceeds the desired level in the permeameter will return to the feed tank, thus maintaining a constant water level in the permeameter.
- Research about drain filter materials.
- Selection of optimum filter/soil combinations.
- Determination of the relative efficiency of drain filter materials.
- Determination of the coefficient of permeability.
- Influence of the hydraulic load variation.