Simultaneous Effect of Perforated and Continuous Walls on the Reduction of Secondary Depth and Relative Energy Drop of Hydraulic Jump in Relaxation Ponds

Subject Areas : hydraulic structures

MOHAMMAD SAEED NAZARIAN ¹ (Department of Civil engineering, Shooshtar Branch, Islamic Azad University, Shooshtar, Iran)
MOHAMMAD HOSSEIN PURMOHAMMADI ² (Department of Water Sciences, Shooshtar Branch, Islamic Azad University, Shooshtar, Iran)

Received: 2020-09-17 Accepted : 2020-09-23 Published : 2020-06-09

Keywords: hydraulic jump, Relaxation pool, Continouous wall, Perforated wall,

Abstract :

When water enters the tondab, it goes fast and has a high speed at the bottom of the tandab. So that the current becomes supercritical and has destructive kinetic energy. Therefore, in order to maintain the natural effects downstream of overflows, including rivers and dams, this energy must be consumed. To achieve this, researchers have sought to create energy dissipators. Among them are relaxation pools. The mechanism of relaxation pool is such that it creates a hydraulic jump in a short distance and then from contact with existing accessories such as calming blocks, just walls, perforated walls to wear out. The energy from the tornado and then the hydraulic jump will help. Many people have tried to use perforated and continuous walls individually or in pairs with different flow conditions and geometric dimensions. Therefore, we decided to control the hydraulic jump by examining the simultaneous use of a pair of perforated and continuous walls with the aim of 1- reducing the secondary depth 2- relative energy loss. For this purpose, by software modeling, a continuous wall with dimensions of 80*13*1 cm and a perforated wall with dimensions of 80*7*1 cm with an optimal distance in FLOW 3D software have been investigated. The result was that using a perforated wall and a continuous wall wasted more energy than other scenarios.