An Experimental Investigation of Convergent Rectangular Surface Jets: Spreading Characteristics of Horizontal Flow over the Bed of Deep and Stagnant Ambient Water

Abstract

This study simulated the operation of discharge ducts in desalination plants to examine the effects exerted by the convergence and longitudinal slope of discharge channels on the spreading of horizontally flowing convergent and inclined rectangular surface jets over the bed of deep and stagnant ambient water. To this end, a 3.2 × 0.6 × 0.9 m3 flume was used, and rectangular channels with convergence angles of 12.5°, 25°, 45°, and 90° were designed. The used jet fluid was a salt water solution with a concentration of 45 g/L. The channels were activated to discharge jet fluid tangentially at a constant depth of 0.7 m into the ambient water surface. After the experiments, data analysis was carried out through image routing. Results indicated that flow distribution over the bed was circular and elliptical. The relationship between radial distance from the impingement point to the outer boundary of flow and time was determined to a power of 0.45 under discharge conditions without a longitudinal slope and to powers of 0.57 and 0.42 under discharge conditions characterized by an inclined slope. Finally, the spreading coefficients of the jets at average, major, and minor radial distances are 4, 2, and 4.5, respectively.