Minor nitpick: fluids are not either liquids or gases, this is particularly true for rocket engines where many of the discussed processes (injection, compression, regenerative coolant flow) actually occur at super- or transcritical conditions.
Also, I don't think you can say the faceplate is heat sink-cooled. Remember that just behind it is the propellant manifold, so it's rather some form of regenerative cooling.
Also, I don't think you can say the faceplate is heat sink-cooled. Remember that just behind it is the propellant manifold, so it's rather some form of regenerative cooling.