Mechanisms of pressure pulse for condensing supersonic steam jet in a rectangular channel

• Published in: Experimental thermal and fluid science Vol. 105; pp. 223 - 233
• Main Authors: Yang, Xiaoping, Fu, Pengfei, Chen, Nana, Liu, Jiping, Wei, Jinjia
• Format: Journal Article
• Language: English
• Published: Philadelphia Elsevier Inc 01.07.2019; Elsevier Science Ltd
• Subjects: Condensation; Confined spaces; Dynamic pressure; High speed photography; Image processing; Industrial areas; Interface stability; Interface wave; Kelvin-Helmholtz instability; Photography; Prediction models; Pressure; Pressure pulse; Propagation; Steam jets; Supersonic steam jet; Transducers; Vapor jets; Wave propagation; Pressure pulse; Supersonic steam jet; Interface wave; Condensation
• ISSN: 0894-1777; 1879-2286
• DOI: 10.1016/j.expthermflusci.2019.04.003

•Growth, propagation, merging and detachment of interface wave was observed.•Interface wave was proved to grow exponentially in axial direction.•Pressure oscillation of supersonic steam jet condensation was induced by interface wave.•A correlation for dominant frequency was proposed based on interface wave propagation. Pressure pulse is a potential risk during the application of condensing supersonic vapor jet in various industrial areas, particularly in a confined space, such as a pipe system. However, the source of pressure pulse remains unknown. In this work, experimental study on the dynamics of condensing supersonic steam jet in a rectangular channel was performed. Interface dynamics were captured by high-speed photography and quantitatively studied via an image-processing technique. The pressure pulse characteristics inside the channel were investigated using dynamic pressure transducers. Results proved that pressure pulse was caused by the growth, propagation, and detachment of interface wave induced by Kelvin-Helmholtz instability for the first time. In addition, the interface wave was proved to grow exponentially by experimental and theoretical methods. The dominant frequency was negative related, whereas its amplitude was positive related to the interface penetration length, which could be explained well by the growth, propagation, and detachment of interface wave. Finally, a prediction model for the dominant frequency was proposed on the basis of the propagation characteristics of interface wave. The proposed model could predict the dominant frequency at a maximum deviation of ±30%.