Classical Venturi flowmeters have been used for decades to measure gas and liquid flow rates. They are based on the principle of fluid mechanics, where a fluid's velocity increases as it passes through a narrow section of the pipe, and the pressure decreases. This decrease in pressure is proportional to the flow rate, and by measuring the pressure difference across the Venturi section, flow rate can be determined.
One of the key advantages of classical Venturi flowmeters is their accuracy, with typical errors ranging from 0.5% to 2%. They are also relatively insensitive to viscosity and density changes, making them suitable for a wide range of applications. However, their installation cost can be higher compared to other flow meters, and they require straight pipe runs upstream and downstream of the Venturi section to maintain accuracy.
In terms of cost, classical Venturi flowmeters can range from several hundred to several thousand dollars, depending on the size and material of construction. However, the long-term benefits of their accuracy and low maintenance costs make them a cost-effective solution for many applications.
Overall, classical Venturi flowmeters remain a popular choice for gas and liquid flow measurement due to their accuracy and reliability. For those interested in implementing a classical Venturi flowmeter, it is important to consider both the initial installation cost and long-term benefits to make an informed decision.