Amirkabir Journal of Civil Engineering

Amirkabir Journal of Civil Engineering

Numerical Investigation of Flow Characteristics in Different Types of Chute Spillway Aerators

Document Type : Research Article

Authors
Fatemeh Safiloo
Farzin Salmasi
Hadi Arvanaghi
Akram Abbaspour
Department of Water Engineering, Faculty of Agriculture, University of Tabriz, Tabriz, Iran
10.22060/ceej.2026.25030.8376
Abstract
Chute spillway aeration plays an important role in protecting chute structures as an effective method to reduce erosion damage caused by cavitation. For this purpose, different types of aerators are used to aerate high-velocity flows. The degree of protection provided by aeration mainly depends on the aerator design and the distribution of air concentration in the flow. In the present study, the characteristics of different chute aerators and their performance are simulated using computational fluid dynamics (CFD) with ANSYS Fluent software. The models used include step aerators, ramp aerators, ramp-step combinations, and floor and sidewall ramp aerators. For hydraulic analysis of the flow, the k-ε RNG turbulence model and the multiphase fluid method were used. For validation, the numerical results were compared with experimental data based on the distribution of air concentration downstream of the aerator, and the results were in acceptable agreement. The findings showed that the combination of the bottom ramp and the side wall provides more effective aeration compared to other methods and improves the efficiency and uniformity of air concentration by forming a cavity region in both the bottom and the wall. In this case, the length of the cavity region is about 50% and the cavitation index is about 55% greater than the conditions using the bottom ramp.
Keywords
Aerator
Bottom Ramp and Side Wall
Cavitation
Cavity Region Length
Turbulence Model
Subjects
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Amirkabir Journal of Civil Engineering
Volume 58, Issue 3
2026
Pages 383-412