Coaxial Injection under Supercritical Conditions
Abstract
This work reports on findings from the initial phase of a coaxial injection process under both subcritical and supercritical conditions. The results presented here are part of a systematic investigation of common rocket engine injectors, such as impinging and coaxial designs. Liquid nitrogen (LN2) is injected through a large length-to-diameter ratio circular hole and exposed at the exit to an annular jet of different gases including nitrogen, helium, and argon. The length-to-diameter ratio is sufficiently large to ensure fully-developed turbulent pipe flow at the exit plane. The behavior of the central LN2 jet has already been analyzed extensively and reported in our earlier published works, for example, Cheliroudi et al. 1, 2. Experiments were conducted by injecting LN2 into a room temperature, high-pressure chamber with full optical access from four directions. The stainless steel chamber can withstand pressures and temperatures of up to 13.6 MPa and 473 K, respectively. Liquid nitrogen is used to cool and/or liquefy the gaseous nitrogen passing through the cryogenic cooler prior to injection. The mass flow rate of the injectant is measured and regulated by way of a mass flowmeter, and a precision micrometer valve. A model K2 Infinity long distance microscope is used to form images of the injected jets on a high resolution CCD camera by the Cooke Corporation.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 2003
- Accession Number
- ADA410921
Entities
People
- Bruce Chehroudi
- Doug Talley