Determination of some hydraulic characteristics of bamboo (Bambusa vulgaris (Schrad)) pipe

Abstract

The hydraulic characteristics (HCs) of any pipe are important in determining its acceptability for water conveyance. Bamboo culms made into pipes by drilling through their septa at the nodes have been in use for many years but very few documented researches have been reported on their HCs. The HCs of Bambusa vulgaris (Schrad) pipe were therefore investigated to contribute to knowledge of its potential usage in irrigation of agricultural land. Three drilling bits namely hole saw drilling bit (HSDB), Ethiopian drilling bit (EDB) and Tanzanian drilling bit (TDB) were studied and compared, in the removal of the septa at the nodes to make bamboo pipes (BPs) from the Bambusa vulgaris culms. Experimental set-ups were made using 9 m length of the BPs to determine hydraulic parameters such as the head loss due to the nodes and the internodes; friction factors and flow types. The data obtained were analyzed using one-way analysis of variance which were further tested using Duncan post-hoc test. The HSDB performed significantly better (p < 0:05) than the TDB and EDB in the smoothness of septa removal at the nodes with the average percentage head loss value of 0.36%, 0.42% and 0.46% respectively. Average friction factor obtained were 0.037, 0 047 and 0.049 for HSDB, TDB and EDB prepared BPs respectively. All these values are within the acceptable limits for a good hydraulic pipe. The flow type through the BPs was turbulent like for most manufactured pipes presently in use for water conveyance. Based on the determined values of its hydraulic characteristics, B.vulgaris pipe is suitable for usage in irrigation and drainage practices.