Hydrodynamic Modification in Channels Densely Populated with Aquaculture Farms

Round 1

Reviewer 1 Report

This study delves into a groundbreaking investigation of the small-scale circulation and hydrodynamics associated with aquaculture infrastructure in the Caucahue channel. The study effectively harnesses computational fluid dynamics (CFD) models to simulate and predict the complex hydrodynamics of the aquaculture sites, marking a significant improvement over traditional methodologies. The successful use of CFD models in tandem with a regional oceanography model allows for a more nuanced understanding of the hydrodynamic effects of aquaculture installations, notably uncovering significant non-local impacts on currents and water circulation.

The study is commendable for its innovative approach, broadening our understanding of hydrodynamic complexities, and highlighting the limitations of conventional methods that oversimplify these dynamics. It effectively presents the case for integrating advanced modelling tools into the management and regulation of aquaculture sites. Furthermore, the findings have implications for improving productivity, suggesting a relationship between velocity magnitude within fish farms and growth rates, which could be harnessed to enhance yields.

Despite its strengths, the study also reveals areas for further research. While CFD models show promise in predicting environmental impacts, it would be beneficial to integrate other components such as Lagrangian models for particle tracking and diffusion models for species transport, as well as factoring in the transport of dissolved elements and organic matter sedimentation. This could provide a more holistic tool for predicting the environmental impacts of the aquaculture industry and contribute to strengthening both productive and environmental management. Moreover, the study could benefit from additional validation, including comparisons with field data across different periods and locations. This could enhance the applicability and generalizability of the results and further establish the relevance of CFD models in aquaculture site management.

     1.    Validation and Generalization: The study seems to be limited to one specific time period and location. How could the research be expanded to include a wider range of locations and time periods to improve the validation and generalization of the model?

2.    Integration of Additional Models: While the CFD model's strength lies in simulating hydrodynamic impacts, other aspects such as particle tracking, species transport, and diffusion of dissolved elements have not been fully integrated into the model. What methodologies could be employed to seamlessly integrate these models to create a more comprehensive simulation?

3.    Accounting for Environmental Impacts: The diffusion of dissolved elements and sedimentation of organic matter are mentioned as potential environmental impacts of aquaculture. How can these elements be effectively included and quantified in the model to provide a more accurate representation of the environmental impact?

4.    Long-term Predictions: The study focuses on short-term, small-scale circulation patterns. How can the model be adapted to make long-term predictions, and what additional data would be required to facilitate this?

5.    Experimental Data Comparison: The study uses CFD simulations, but how can these be complemented with actual experimental data to validate the findings and ensure the model's accuracy?

The answers to the questions must be reflected in the text.

Author Response

Dear Reviewer, 

Please find reply on attached file.

Regards.

Author Response File: Author Response.docx

Reviewer 2 Report

The authors performed a numerical study on the Hydrodynamic modification in channels densely populated with aquaculture farms. The results are interesting, the paper is well prepared and has good scientific soundness. The paper can be accepted after addressing the following comments:

The main qualitative results are to be mentioned in the abstract.

The novelty of the paper is to be clearly stated.

the solved governing equations are to be presented.

The boundary conditions are to be expressed mathematically.

A grid sensitivity test is to be performed.

The used turbulence model is to be justified.

What is convergence criterion?

The characteristics of the used computer and the computational time are to be provided.

It will be interesting to present the flow structure (Figs 12 and 13) by streamlines instead of the velocity vectors.

Author Response

Dear Reviewer, 

Please find reply on attached file.

Regards.

Author Response File: Author Response.docx