A publication is forthcoming on the topic of injection pressure and oxygen concentration effects when using simultaneous schlieren and formaldehyde/PAH laser-induced fluorescence.

Simultaneous schlieren (100 kHz) and formaldeyhde/PAH planar LIF (50 kHz) were performed to characterize the low- and high-temperature ignition events. Conditions are for n-dodecane Spray A-3 flames (0.094 mm orifice) into 899* K, 22.8 kg/m3, 6 MPa environment. The default fuel injection pressure and temperature are 150 MPa and 363 K, respectively, with the following variations:

Ambient oxygen volume percent	Injection Pressure	Movie
13%	150 MPa	Schlieren_LIF_13percent
15%	150 MPa	Schlieren_LIF_15percent
21%	150 MPa	Schlieren_LIF_21percent
15%	50 MPa	Schlieren_LIF_50MPa
15%	100 MPa	Schlieren_LIF_100MPa

See links to other Spray A-3 movies at this condition at Sim et al. PROCI 2020 Pulse-burst formaldehyde