Open AccessEFFECT OF COFLOW ON SONIC JET
Author(s) -
Shalini Rajkumar,
Sanjay Kumar,
Parthasarathy Vasanthakumar
Publication year - 2021
Publication title -
journal of physics. conference series
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.21
H-Index - 85
eISSN - 1742-6596
pISSN - 1742-6588
DOI - 10.1088/1742-6596/2054/1/012079
Subject(s) - shadowgraph , jet (fluid) , nozzle , core (optical fiber) , elongation , overall pressure ratio , materials science , mechanics , aerospace engineering , composite material , physics , ultimate tensile strength , engineering , gas compressor
The sonic coflow effect on the core length of sonic primary jet was experimentally investigated in this research work. A circular convergent nozzle was used for both core and coflow jet studies. The 1mm annular gap was maintained between the coflow and core nozzles. The nozzle pressure ratio (NPR) was varied from 3 to 5, insteps of 1 for both the nozzles. For each primary NPR, the NPR of coflow was varied, and the shadowgraph flow visualization was carried out. From the shadowgraph visualization results it was observed that the sonic primary jet core length increases with increasing pressure ratio without coflow. With sonic coflow, the primary jet core length started to increase further with increasing coflow NPR. That is, the increase of sonic coflow NPR at each sonic primary jet NPR resulted in the elongation of core. Therefore, the introduction of coflow has resulted in core length elongation at all the levels of underexpansion. The primary jet core elongation due to the presence of coflow resulted in the weakening of shock strength in the primary jet core.