Skip to main content
Log in

New correlation of subsonic, supersonic and cryo gas jets validated by highly accurate schlieren measurements

  • Research Article
  • Published:
Experiments in Fluids Aims and scope Submit manuscript

Abstract

High-speed schlieren visualization at 20,000 fps was performed to investigate the transient penetration depth of helium gas jets into air at 8 different pressure ratios. The injection pressure investigated was between 1.5 and 40 bar. The pressure in the mixing chamber was varied between 1.0 and 4.0 bar. The different pressure ratios were chosen to examine subsonic and underexpanded jets. To investigate the density dependence of the process, cryo injections were performed at injection temperatures of 224, 198 and 173 K at different pressure ratios. Using the image processing technique for detecting the jet tip penetration distance, presented in this article, it can be shown that for a given injector the jet penetration behavior is the same for the same pressure ratio. A new self-similar model was developed, to describe the influence of the injection and chamber gas density on the jet penetration behavior more accurately. The model was verified with the experimental data sets presented in this paper and with literature data.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8
Fig. 9
Fig. 10
Fig. 11
Fig. 12
Fig. 13
Fig. 14
Fig. 15
Fig. 16
Fig. 17
Fig. 18
Fig. 19

Similar content being viewed by others

Abbreviations

a :

Unobstructed height of source image (m)

B :

Empirical constant (−)

C D :

Discharge coefficient (−)

C f :

Fraction of centerline velocity (−)

C t :

Scaling constant (−)

D :

Diameter of vortex ball (m)

d :

Nozzle diameter (m)

d e :

Effective diameter (m)

d PMD :

Diameter of the PMD (m)

E BG :

Background illuminance (lux)

\(\Updelta E\) :

Differential illuminance (lux)

f 2 :

Focal length of second mirror (m)

h :

Image height (−)

I :

Jet image (−)

\(\tilde I\) :

Normalized jet image (−)

I BG :

Background image (−)

\(\tilde I_{\rm BG}\) :

Normalized background image (−)

k :

Gladstone-Dale constant (−)

K :

Entrainment constant (−)

l K :

Kolmogorov length scale (m)

l T :

Taylor length scale (m)

M jet :

Momentum of steady-state jet region (kg m/s)

M vortex :

Momentum of jet vortex ball (kg m/s)

M PMD :

Mach number downstream of the PMD (−)

M u,s :

Mach number upstream of normal shock (−)

\(\dot M_{\rm n}\) :

Momentum flux at nozzle exit (kg m/s2)

\(\dot{m}\) :

Massflow (kg/s)

\(\dot{m}_{\rm n}\) :

Massflow at nozzle exit (kg/s)

\(\dot m_{\rm m}\) :

Measured massflow through nozzle (kg/s)

n :

Refractive index (−)

p ch :

Chamber pressure (bar)

p i :

Injection pressure (bar)

p n :

Pressure at nozzle exit (bar)

R :

Empirical constant (−)

R ch :

Specific gas constant of chamber gas (J/kg K)

R n :

Specific gas constant of injected gas (J/kg K)

Re :

Reynolds number (−)

Re T :

Taylor-scale Reynolds number (−)

Re 0 :

Characteristic jet Reynolds number (−)

r :

Radial distance from jet axis (m)

S :

Schlieren sensitivity (−)

T ch :

Chamber temperature (K)

T i :

Injection temperature (K)

T n :

Temperature at nozzle exit (K)

t :

Time (s)

t + :

Characteristic time scale (s)

\(\tilde t\) :

Non-dimensional time scale (−)

\(\tilde{t}_{\rm P}\) :

Normalized time according to Petersen (−)

u′:

r.m.s. velocity (m/s)

U c :

Centerline velocity (m/s)

U c,m :

Centerline mean velocity (m/s)

U n :

Velocity at nozzle exit (m/s)

U PMD :

Velocity downstream of the PMD (m/s)

w :

Image width (−)

x :

Position (m)

x 0 :

Virtual origin (m)

y 0.5 :

Half-width of jet (m)

z :

Position along the optical axis (m)

z + :

Characteristic length scale (m)

Z t :

Penetration depth (m)

\(\tilde{Z}_{\rm t,l}\) :

Normalized Z t (\(s^{\frac{1}{2}}\))

\(\tilde{Z}_{\rm t}\) :

Non-dimensional Z t (−)

\(\tilde{Z}_{\rm t,H}\) :

Normalized Z t according to Hill \((s^{\frac{1}{2}})\)

\(\tilde{Z}_{\rm t,P}\) :

Normalized Z t according to Petersen (−)

\(\epsilon\) :

Dissipation rate (m2/s3)

\(\hat{\epsilon}\) :

Dissipation rate constant (−)

\(\epsilon_y\) :

Light ray deflection in y direction (rad)

\(\Upgamma\) :

Scaling constant (−)

\(\tilde \Upgamma\) :

Scaling constant (−)

γ:

Specific heat ratio (−)

γ n :

Specific heat ratio at nozzle exit (−)

μ :

Mean pixel intensity of a image (−)

ν:

Kinematic viscosity (m2/s)

νn :

Kinematic viscosity at nozzle exit (m2/s)

πi :

Injection pressure ratio (−)

ρ:

Gas density (kg/m3)

ρch :

Chamber gas density (kg/m3)

ρi :

Injection gas density (kg/m3)

ρn :

Gas density at nozzle exit (kg/m3)

ρPMD :

Density downstream of the PMD (kg/m3)

DI :

Direct injection

LNG :

Liquefied natural gas

PFI :

Port fuel injection

PMD :

Pseudo-Mach disk

References

  • Abraham J (1996) Entrainment characteristics of transient jets. Numer Heat Transf Part A 30:347–364

    Article  Google Scholar 

  • Abramovich S, Solan A (1973) The initial development of a submerged laminar round jet. J Fluid Mech 59:791–801

    Article  Google Scholar 

  • Anderson J (2003) Modern compressible flow: with historical perspective, 3rd edn. McGraw-Hill, New York

    Google Scholar 

  • Antonia RA, Satyaprakash BR, Hussain AKMF (1980) Measurements of dissipation rate and some other characteristics of turbulent plane and circular jets. Phys Fluids 23:695–700

    Article  Google Scholar 

  • Baert R, Klaassen A, Doosje R (2010) Direct injection of high pressure gas: scaling properties of pulsed turbulent jets. SAE-Paper 2010-01-2253

  • Birch AD, Brown DR, Dodson MG, Swaffield F (1984) The structure and concentration decay of high pressure jets of natural gas. Combust Sci Technol 36:249–261

    Article  Google Scholar 

  • Chen CJ, Rodi W (1980) Vertical turbulent buoyant jets: a review of experimental data. Pergamon Press, Oxford

    Google Scholar 

  • Edwards R, LarivT JF, Beziat JC (2011) Well-to-wheels analysis of future automotive fuels and powertrains in the European context. Well-to-Wheels Rep version 3c

  • Ewan BCR, Moodie K (1986) Structure and velocity measurements in underexpanded jets. Combust Sci Technol 45:275–288

    Article  Google Scholar 

  • Gabside JE, Hall AR, Townend DTA (1943) Flow states in emergent gas streams. Nature 748–748

  • Grabner P, Eichlseder H, Gerbig F, Gerke U (2006) Optimization of a hydrogen internal combustion engine with inner mixture formation. In: First international symposium in hydrogen internal combustion engines

  • Heller K, Ellgas S (2006) Optimization of a hydrogen internal combustion engine with cryogenic mixture formation. In: First international symposium in hydrogen internal combustion engines

  • Hill PG, Ouellette P (1999) Transient turbulent gaseous fuel jets for diesel engines. J Fluids Eng 121:93–101

    Article  Google Scholar 

  • Kayser JC, Shambaugh RL (1991) Discharge coefficients for compressible flow through small-diameter orifices and convergent nozzles. Chem Eng Sci 46(7):1697–1711

    Article  Google Scholar 

  • Merzkirch W (1987) Flow visualization, 2nd edn. Academic Press, New York

    Google Scholar 

  • Naber JD, Siebers DL (1996) Effects of gas density and vaporization on penetration and dispersion of diesel sprays. SAE-Paper 960034

  • Ouellette P (1996) Direct injection of natural gas for diesel engine fueling. PhD thesis, University of British Columbia

  • Petersen B (2006) Transient high-pressure hydrogen jet measurements. Master’s thesis, University of Wisconsin-Madison

  • Petersen B, Ghandhi J (2006) Transient high-pressure hydrogen jet measurements. SAE-Paper 2006-01-0652

  • Pope SB (2000) Turbulent flows, 1st edn. Cambridge University Press, Cambridge

    Book  Google Scholar 

  • Ricou FP, Spalding DB (1961) Measurements of entrainment by axisymmetrical turbulent jets. J Fluid Mech 11:21–32

    Article  MATH  Google Scholar 

  • Rizk W (1958) Experimental studies of the mixing processes and flow configurations in two-cycle engine scavenging. Proc Inst Mech Eng 172:417–437

    Article  Google Scholar 

  • Schlichting H (1976) Grenzschicht-Theorie, 5th edn. Springer, Karlsruhe

    Google Scholar 

  • Settles G (2001) Schlieren and shadowgraph techniques. Springer, Berlin

    Book  MATH  Google Scholar 

  • Sutherland W (1893) The viscosity of gases and molecular force. Philosoph Mag Ser 5 36(223):507–531

    Article  MATH  Google Scholar 

  • Turner JS (1962) The ’starting plume’ in neutral surroundings. J Fluid Mech 13:356–368

    Article  MATH  Google Scholar 

  • Vogl P, Zimmermann I, Pfitzner M (2006) Modelling of hydrogen injection and combustion in internal combustion engines. First international symposium in hydrogen internal combustion engines

  • Wakuri Y, Fujii M, Amitani T, Tsuneya R (1960) Studies on the penetration of fuel spray in a diesel engine. Bull JSME 3(9):123–130

    Article  Google Scholar 

  • Williams TC, Shaddix CR (2007) Simultaneous correction of flat field and nonlinearity response of intensified charge-coupled devices. Rev Sci Instrum 78:1–6

    Google Scholar 

  • Witze PO (1980) The impulsively started incompressible turbulent jet. SAND80-8617

Download references

Acknowledgments

The authors would like to thank F. Gerbig from BMW for providing the cryo system for the low temperature injections.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to J. Gerold.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Gerold, J., Vogl, P. & Pfitzner, M. New correlation of subsonic, supersonic and cryo gas jets validated by highly accurate schlieren measurements. Exp Fluids 54, 1542 (2013). https://doi.org/10.1007/s00348-013-1542-2

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • DOI: https://doi.org/10.1007/s00348-013-1542-2

Keywords

Navigation