Abstract: A system for refrigerant leakage detection includes one or more sensors configured to detect one or more parameters of a building system including a refrigerant. The system further includes one or more storage devices storing instructions thereon that, when executed by one or more processors, cause the one or more processors to receive sensor data from the one or more sensors; apply the sensor data to a long short-term memory (LSTM) model to generate predicted sensor data corresponding to the one or more sensors; receive subsequent sensor data from the one or more sensors; compare the predicted sensor data to the subsequent sensor data; determine that the building system has a refrigerant leakage based on the comparison of the predicted sensor data to the subsequent sensor data; and, responsive to determining that the building system has the refrigerant leakage, take an action to address the refrigerant leakage.

Abstract: The disclosure provides a three-way structure, including a straight tube and a branch tube perpendicular to and connected with the straight tube, is characterized in that the inner surface of the straight tube is provided with a hollow structure surrounding the straight tube. The three-way structure of the disclosure can both attenuate the noise and simplify the pipeline arrangement of the unit.