In an open channel flow operation, there are several issues that can interfere with the normal functioning of your system, including submergence. While submergence should be a concern for almost every open channel flow system, few people understand the ins and outs of this type of flow conditions. Here are a few important facts about submergence that you should keep in mind so that nothing interferes with the normal functioning of your flow management operation.
What is Submergence?
When we talk about submergence, we’re basically discussing the downstream conditions in your system. Submergence occurs when the downstream water level rises to the point that it interferes with the flow exiting your flume. If downstream conditions prevent flow from freely flowing out of your flume, the water level in your flume will increase.
At a certain point, the flow in your system may back up to the point that your flume is completely covered, or submerged. Although most flumes can still operate under submerged flow conditions, your operators will need to perform advanced calculations to continue accurately measuring the flow in your system. If your operators are inexperienced with submergence, the success of your organization will be limited when these conditions are present.
Flumes that Are Affected
One of the most important facts about submergence that you need to understand is every flume you could install in your operation will be vulnerable to these conditions. While some flumes are more resistant to submergence than others, all flumes can experience submerged flow conditions if you’re not careful.
Fortunately, several flume styles can be corrected for submergence, including popular options such as the Cutthroat flume and Parshall flume. Some flumes, unfortunately, cannot be corrected for submergence, including the RBC flume and Palmer-Bowlus flume.
Is Correcting for Submergence the Right Choice?
As mentioned in the previous section, many of the most popular flumes in the world can be corrected to prevent submergence. The question, however, is if correcting for submergence is actually a good idea.
In general, correcting for submergence is not the best idea for most operations. For one, correcting for submergence can be expensive. So, if you’re looking to control your installation costs, it’s better to install your flume for free-flow conditions. Correcting for submergence can also make your operators job more difficult, as they will need to take measurements in two different locations.
Submergence and Flow Rate
When trying to determine your risk for submergence, remember the flow rate in your system has no influence. With submergence, only the downstream conditions matter. Even systems with low flows are at risk for submergence if the downstream conditions are right. If you want to know if you should be wary of submerged flow conditions, closely examine the channel downstream of your flume.
Purchase the Right Flume
Now that you know a few crucial facts about submergence, you can prevent these conditions in your system by purchasing the right flume from Tracom, FRP. We are proud to offer a wide range of quality flumes, including styles resistant to submerged flow conditions. Request a quote from Tracom today so that you can install a dependable flume in your open channel flow operation.
