Laser Diagnostics in Flows and Combustion

Laser Diagnostics in Flows and Combustion

  • Jonathan Brulatout added an answer:
    Are the assumptions of isothermal and steady injection still reasonable in contemporary injection strategies?
    In view of the contemporary fuel injection strategies, e.g. pulse injection or split injection; could the continuous assumptions of isothermal and steady injection in the modelling of liquid breakup be justified?
    Jonathan Brulatout · École de Technologie Supérieure
    Thank you for this complete answer with which I agree. Indeed, in the literature, CFD studies implying breakup models show that the transient part of the spray development is usually hard to predict accurately, when comparing to experimental data. Of course, CFD implies other problems but this is one of the causes of this discrepency... Also, I spoke with a colleague who made an experimental study on the injection rail and injector for this type of strategies using short injections. In addition to the needle lift problem well presented by L. Postrioti, there is also some pressure waves travelling in the system which can interact with the next injection, in particular with the injection rate. This phenomenon could have also an influence on the breakup rate through the injection velocity. Speaking with an other investigator, he showed me that partial needle lift also appear to have a great influence on the turbulence inside the nozzle. As this turbulence is recognized as one of the causes of first atomization, in my opinion, this should have a significant influence on the droplet breakup.
  • Closed account added an answer:
    CO2-Rayleigh-Calibration for UV-LIF-Measurements at atmospheric pressure plasma
    Hi, I searched by myself, but was not very succesfull in finding satisfying information about CO2-crosssection for Rayleigh-Scattering of UV (245 to 250 nm) at roomtemperature and atmospheric pressure in right angle to the laserpath. Can somebody please help me out? Thanks & good measuring. T. Schumann
    Problem solved. mfG
  • Gregor C. Gebel added an answer:
    accuracy of k(T)
    hi , Do some of you know how accurate the k(T) kinetics constants are? (which are usually measured with shock tubes)
    Gregor C. Gebel · German Aerospace Center (DLR)
    Hi, I do not have any experience with shock tube experiments, but when my collegues from the kinetics department show their results in a presentation, they use a logarithmic scale for k and a linear one for T. Ordinate values usually scatter heavily, so I believe, with respect to the logarithmic scale, the accuracy is not too good, uncertainties of 100 % or more may occur. Here is a paper, which may give you more detailed infromation: http://pubs.acs.org/doi/abs/10.1021/j100469a023 Best wishes, Greg

About Laser Diagnostics in Flows and Combustion

A group for researchers who want to share knowledge and experience in laser measurement techniques

Topic Followers (838) See all