Ultrasonic flowmeters use sound waves to determine the velocity of a fluid flowing in a pipe. At no flow conditions, the frequencies of an ultrasonic wave transmitted into a pipe and its reflections from the fluid are the same. Under flowing conditions, the frequency of the reflected wave is different due to the Doppler effect. When the fluid moves faster, the frequency shift increases linearly. The transmitter processes signals from the transmitted wave and its reflections to determine the flow rate. Continue reading “How Ultrasonic Flowmeters Work”

## Measuring Thermal Energy in Hydronic Systems

So you’ve decided to track how much energy your HVAC system consumes in order to increase the system’s energy efficiency — great! But how will you do it? There are multiple methods that can be used to measure thermal energy in hydronic systems. We’ve outlined several methods below to make it easier for you to select the best technology for your application.

Measuring thermal energy requires three components: a fluid flow sensor, two temperature sensors (one for inlet temperature, one for outlet temperature), and a calculator. Although thermal energy can technically be measured without a calculator, doing an energy calculation by hand is very complex and can introduce manual calculation error into the measurement. For that reason, we recommend incorporating a calculator into your system for the most accurate energy measurements. This calculator can be either an independent BTU controller, part of your building management system, or integral to a complete thermal energy system. A complete system includes a flowmeter, temperature sensors, and a calculator that are all calibrated together, eliminating the need for multiple pieces of equipment. Continue reading “Measuring Thermal Energy in Hydronic Systems”