Dhi Mike 21 May 2026

, developed by , is a professional engineering software suite for simulating 2D free-surface flows in estuaries, coastal waters, and seas. It is primarily used when vertical stratification can be neglected, focusing on depth-averaged water environments. www.dhigroup.com Core Capabilities MIKE 21-3 | Coast and Marine Water Modelling Software - DHI

, developed by the Danish Hydraulic Institute (DHI) , is a professional 2D modeling suite used to simulate hydraulics and environmental phenomena in coastal waters, estuaries, rivers, and lakes. www.dhigroup.com Core Capabilities The software is primarily used for two-dimensional free-surface flows

where vertical stratification can be neglected. Its applications include: ScienceDirect.com Hydrodynamics (HD):

Simulating water level variations and flows in response to various forces. Spectral Waves (SW):

Modeling the growth, decay, and transformation of wind-generated waves and swells. Environmental Impact:

Analyzing water quality, sediment transport, and oil spills. Flood Modeling: Predicting urban flooding, dam breaches, and storm surges. ScienceDirect.com MIKE Powered by DHI | Water Modelling Software

MIKE 21, developed by DHI (Danish Hydraulic Institute), is a professional engineering software suite used globally for 2D numerical modeling of hydrodynamics, waves, sediment transport, and water quality in coastal and marine environments. Core Capabilities & Modules

MIKE 21 is highly modular, allowing users to customize the engine based on specific project needs:

Hydrodynamics (HD): The core engine that simulates water level variations and flows in response to forcing functions like tides, wind, and river discharge. dhi mike 21

Spectral Waves (SW): Simulates the growth, decay, and transformation of wind-generated waves and swells in offshore and coastal areas.

Environmental (ECO Lab): Used for water quality analysis, including bacterial survival, oxygen conditions, and nutrient levels.

Sediment & Morphology: Modules like ST (Sediment Transport) and LITPACK predict shoreline evolution and bed level changes. Comparative Strengths

Reviewers and comparative studies often highlight how it stands up against other tools like HEC-RAS:

Mesh Flexibility: One of its primary advantages is the Unstructured Grid (Flexible Mesh). This allows for high-resolution modeling in areas of interest (like complex coastlines) while keeping a coarser mesh in open water, which optimizes computational time.

Modeling Accuracy: In comparative flood simulations, MIKE 21 is noted for its ability to handle complex streamflows and unsteady flow conditions with high accuracy.

Broad Application: It is a "one-stop-shop" for everything from coastal defense design (like seawalls) to analyzing the impact of marine sand mining or wave energy converters.

Introduction

DHI Mike 21 is a comprehensive software package used for hydrodynamic modeling and simulation of coastal and estuarine systems. Developed by DHI (Dansk Hydraulik Institut), Mike 21 is widely used by researchers, engineers, and coastal managers to understand and predict the behavior of complex coastal systems. This paper provides an overview of the Mike 21 software, its features, and applications.

Overview of Mike 21

Mike 21 is a 2D hydrodynamic model that simulates the flow of water in rivers, estuaries, and coastal areas. The software uses a finite difference approach to solve the shallow water equations, which describe the motion of water in these systems. Mike 21 is designed to handle complex geometries, including irregular coastlines, islands, and tidal flats.

Key Features of Mike 21

Some of the key features of Mike 21 include:

Applications of Mike 21

Mike 21 has a wide range of applications in coastal engineering, research, and management. Some examples include:

Case Studies

Several case studies have been conducted using Mike 21 to demonstrate its capabilities and applications. For example:

Conclusion

DHI Mike 21 is a powerful software package for hydrodynamic modeling and simulation of coastal and estuarine systems. Its comprehensive features and applications make it a valuable tool for researchers, engineers, and coastal managers. The software has been widely used in various case studies to simulate complex coastal processes and to inform decision-making. As coastal systems continue to face challenges from climate change, human activities, and other stressors, Mike 21 will remain an essential tool for understanding and managing these complex systems.

References

Developers use MIKE 21 to assess tidal currents and wave loads on turbine foundations. It also models sediment scour around monopiles.

This is the foundation of all analyses. The HD module computes water levels and flow velocities. It accounts for:

Using the MIKE Zero Mesh Generator (or third-party tools like SMS), create a computational mesh. For structured grids, use the old MIKE 21 Grid Generator. For FM, ensure triangles have aspect ratios <10 and smooth transitions.

Key data inputs:

Simulates wave generation, propagation, and dissipation from wind. Includes: