Parshall Flume vs. Cutthroat Flume

In an open channel flow operation, the most important decision you can make is what type of flume you’ll use in your system. While there are a variety of available flumes, all of which have their benefits, two of your best options are the Parshall flume or Cutthroat flume.

Because these two flume types are so useful, it can be hard to choose between them, making it a good idea to examine them a little more closely so that you can pick the right device for your operation. Here is some information about the differences between the Parshall flume and Cutthroat flume that will help you choose the right device for you.

Design Differences

One of the most important factors to consider when choosing between a Cutthroat and Parshall flume is the design of each device. Although they may seem similar at first glance, there are some big differences that you need to keep in mind.

Let’s start by discussing the similarities between these flumes. Both devices, for instance, have an hourglass shape. Also, the discharge walls of each of these flumes flare outwards. Other than these two issues, Parshall flumes and Cutthroat flumes are very different.

One of the biggest differences between these two flumes styles involves the throat section. The Cutthroat flume does not possess a throat. section, whereas as the Parshall flume does offer this feature. Another major difference between these flumes has to do the outlet wall’s angle of divergence. In Cutthroat flumes, this angle is fixed, and in Parshall flumes, the angle can vary from device to device.

Floors, Sidewalls, and Accuracy

We’ve discussed some design differences between these two flumes, but we still need to discuss some of the characteristics of the sidewalls and floors of each device. One of the most distinctive features of the Parshall flume is the drop in floor elevation. Cutthroat flumes do not possess this feature, as the floor of this flume is completely flat.

The sidewalls of these flumes are also very different, although they will be vertical in both flumes. The height of a Parshall flume’s side walls can be different from flume to flume, and will depend on the needs of your operation. On the other hand, the sidewalls of a Cutthroat flume will always a third of the length of the flume.

When it comes to accuracy, both flumes make an excellent choice. Whichever flume you choose, you should be easily able to take accurate flow readings, increasing the success of your operations. In some situations, the Cutthroat flume may be a little more accurate, but not to a significant degree.

Choose Your Flume

Now that you know a little more about Cutthroat flumes and Parshall flumes, you should be able to pick the device that best fits the needs of your system. If you need a little help choosing your flume, however, you should work with the experts at Tracom, FRP.

Tracom offers a variety of fiberglass flumes, including the popular Parshall and Cutthroat styles, and we would be glad to help you choose the device that will work for you. Contact us today for more information about our products.