Sankey diagrams are a visual tool widely used in engineering, science, and other disciplines to represent the flow of energy or materials in a process. They provide a clear and concise way to interpret complex data, making it easy to understand the key aspects of a system’s efficiency and structure. This guide will help you master the creation and interpretation of Sankey diagrams for material analysis in engineering and science. By the end of this article, you’ll be equipped with the knowledge and skills needed to effectively use Sankey diagrams in your work.
### Understanding Sankey Diagrams
#### Definition and Structure
A Sankey diagram is a type of flow diagram where the width of an arrow represents the quantity of material or energy being transferred. Typically, Sankey diagrams display a process from start to finish, with arrows flowing between different components and representing the flow of material or energy.
#### Components of a Sanky Diagram
1. **Arrow width**: Indicates the amount of material or energy.
2. **Flow direction**: Shows the path of material or energy.
3. **System boundaries**: Outline the process or system being analyzed.
4. **Processes**: Represent the steps in the process, where arrows connect them.
5. **External inputs and outputs**: Show matter or energy entering or leaving the system.
6. **Intermediate exchanges**: Represent the material or energy exchanges between processes.
### Creating Sankey Diagrams
#### Choosing Software
Selecting a tool to create Sankey diagrams is crucial for your work. Several tools are available, ranging from free open-source software to proprietary applications. Examples include:
– **Open Energy Modeller (OEM)**
– **Process Simulate (Siemens)**
– **Sankey Tool**
– **Excel with Sankey plugin**
#### Step-by-Step Guide
1. **Define the process**: Outline the steps and components involved in your material or energy analysis.
2. **Determine the arrow sizes**: Decide the flow rates for each step and scale them appropriately in the software.
3. **Establish connections**: Connect the processes with arrows indicating the flow of material or energy.
4. **Adjust aesthetics**: Tailor the colors, fonts, and other visual elements to best convey the information.
5. **Finalize and review**: Ensure the diagram is clear and accurately represents the material or energy flow.
### Interpreting Sankey Diagrams
#### Analyzing the Diagram
1. **Identify bottlenecks**: Look for areas where the arrow width narrows, indicating a decrease in flow. These bottlenecks might be the most critical areas to address for improved efficiency.
2. **Evaluate energy/flow balance**: Examine how external inputs and outputs are distributed throughout the system.
3. **Highlight energy loss**: Note the arrows entering or leaving as a result of inefficiencies, such as heat loss or material waste.
#### Best Practices
– **Be consistent**: Apply a consistent scale and units to keep the interpretation straightforward.
– **Zoom in on key sections**: If necessary, create sub-diagrams to focus on critical aspects of the process.
– **Use annotations**: Clarify information with annotations, particularly in complex diagrams.
### Conclusion
Sankey diagrams are an invaluable tool for engineers and scientists looking to analyze the flow of material and energy. By following this guide, you can effectively create and interpret Sankey diagrams, leading to better understanding and optimization of your system or process. As you practice and refine your skills, you’ll find that Sankey diagrams become an indispensable part of your analytical toolkit.
