Setting Up a Flow Bench Simulation in SolidWorks: A Step-by-Step Guide

Welcome back to the CFD Simulation Using SolidWorks series! In this blog, we’ll walk you through the process of setting up a flow bench simulation in SolidWorks. Flow benches are widely used to design and test intake ports in engines, giving insight into the flow characteristics and pressure losses. This tutorial is perfect for anyone learning computational fluid dynamics basics and looking to apply their knowledge in a real-world scenario. 

What Is a Flow Bench? 

A flow bench is a device used to test and analyze the performance of an intake port. It simulates the conditions inside an engine without the need for exhaust gases. The goal is to understand how the intake port affects flow behavior, particularly pressure losses and mass flow rates. In this example, we’ll use a simplified port with an open valve to illustrate the process. 

If you’re following this as part of a computational fluid dynamics course, this project will be both educational and practical, helps developing CFD basics for mechanical engineers. 

Step 1: Understanding the Geometry 

The geometry in this simulation is simplified, with the valve open at an arbitrary value. In practice, you would conduct a valve lift study to analyze how different valve lifts affect the flow. The idea is to simulate the flow through the chamber and determine the pressure loss across the intake port. A well-designed port should minimize pressure loss, as excessive pressure loss increases the pumping cost. 

For this project, you’ll need to create your own geometry. Feel free to experiment with different port shapes, such as a helical port, which is commonly used in diesel engines to promote swirl (the fluid’s rotation about a vertical axis). If you decide to try a helical port, it would be interesting to compare results. 

Step 2: Setting Up the CFD Simulation 

For the simulation, we’ll be using steady-state analysis in CFD with SolidWorks. Here’s a brief overview of how to set it up: 

1. Inlet and Outlet: Define the inlet and outlet conditions. In this case, we have a simple inlet and outlet configuration, with the flow designed to move around the valve. 

2. Mesh Refinement: Use a refined mesh to capture the flow details around the valve. Depending on your computer's processing power, you may not be able to achieve extremely fine meshes, but try to refine the mesh as much as possible. Local refinements around the valve are important to accurately simulate the flow behavior. 

In my simulation, I’ve applied a local refinement with a refinement level of 5 around the valve. This ensures that the cells in contact with the valve are smaller, capturing the finer details of the flow. 

1. Running the Simulation: Once the setup is complete, run the simulation. In this example, I already have results after 0.4 seconds of simulation time. 

2. 
   

Step 3: Visualizing the Results 

After running the simulation, it’s time to visualize and interpret the results. 

1. Cut Plot: Start by generating a cut plot to view the flow through the intake port. Hide the engine geometry to focus on the flow field. In this case, the peak velocity is around 280 m/s, which you can observe in the plot. This helps you understand how the flow moves through the intake port and around the valve. 

2. Flow Trajectories: Next, use flow trajectories to visualize the complex flow structures generated in the intake port. For instance, you can start by selecting 20 points to get a rough idea, then refine the plot by increasing the number of points (e.g., to 150 points) for a more detailed view. This gives you a clear picture of the flow dynamics, including velocity patterns and flow separation points. 

By hiding the surface plot, you can observe the detailed flow structures that develop in the intake port. The flow paths look visually striking and offer valuable insights into the airflow’s behavior. 

Step 4: Analyzing Mass Flow Rate and Pressure Loss 

Apart from the cool visuals, the main goal is to analyze the mass flow rate and pressure loss. Here's what you need to focus on: 

1. Mass Flow Rate: Measure the mass flow rate through the intake port at different valve lifts. This is critical to understanding how efficiently air moves through the port. You’ll also need to create a plot showing how the mass flow rate changes with varying valve lift analyze the results in your project. 

2. Pressure Loss: Determine the pressure loss across the intake port, as minimizing pressure loss is a key factor in intake port design. A well-designed port will have minimal pressure loss, which improves the overall engine performance by reducing pumping costs. 

Step 5: Advanced Flow Bench Applications 

This project is an excellent introduction to flow bench simulations, but it has real-world applications in industries like automotive design. Companies such as General Motors and the Automotive Research Association of India (ARAI) use flow benches to test and improve intake port designs. They evaluate parameters like swirl to optimize engine performance. 

Intake port simulations are critical in optimizing engine design, and mastering these skills will set you apart in the job market. 

Conclusion 

In this blog, we explored how to set up and run a flow bench simulation in SolidWorks, focusing on visualizing flow patterns, measuring mass flow rate, and calculating pressure loss. This hands-on project offers a great way to apply CFD basics for mechanical engineers and is an essential part of learning CFD using SolidWorks. 

Hope this guide gives you the confidence to tackle your flow bench project. Best of luck, and feel free to share your results! 

Happy simulating! 

 This blog is part of our ongoing series on CFD Simulations using SolidWorks.   

If you missed the previous posts, check them out here.  

Would you like to have a more interactive demonstration of the above concepts? 

Skill-Lync has released a FREE comprehensive course covering CFD Simulations using SolidWorks in detail! Check it out here. 

Right from the user interface's fundamentals, menus and options, this course covers most aspects of the tool from a practical perspective. It even includes a certificate to add to your resume after completion! 

Check out our hands-on course today and add SolidWorks to your list of skills!  

Let’s get #IndustryReady together, one skill at a time! 

Start Course Now