At the laboratory, we have used an ac power supply to generate atmospheric DBD. However, I have come across some papers about the use of the DC power supply for its generation. What significant behavior is there in terms of discharge phenomena apart from the fact that dielectrics block dc?
I really need help with this.
Thank you so much Mohamed Azab for your response!
Is the convenient availability the only option to use AC power supply for the plasma generation? Which one is a more stable AC power supply or DC power supply? Can you please help me with this?
First of all, as said Mohamed Azab its availability. Second, AC discharge physical properties are very different from DC discharge. Natural atmospheric DBD using only DC discharge. Using AC discharge lifetime of plazma is very long (ms or tens even hundreds of ms). Very difficult to create discharge using AC PS during a few microseconds. DC discharge system used DC PS only for charging the HV capacitor. Depend on discharge time electrohydraulic shock can be soft, middle, and hard. It`s mean the instant pressure and temperature level (up to 10000 atm and 5000K based on experimental measurements). We have some experiments for algae cell destruction using soft or middle electrohydraulic shock (underwater HV DC discharge during a few microseconds). In this case, power density is very high.
Thank you so much Professor Sergejus Borodinas for your illustration. I really appreciate it!
if we use DC power supply, we will have a discharge. but after that, the charge carriers will get trap by the dielectric. then they will make a field in the opposite direction of the external field that we had from our power supply. finally, this situation will kill discharge. but when we use AC or pulse DC, when the external field changes its direction, the internal filed that are made by charge carriers will make a discharge. and this behavior will happen again and again by any direction change of the external field.