leader discharge occurs in lightning discharges and the breakdown of gas insulated apparatuses. The generation of electrons in leader channel is dominated by associate ionization, whose reaction rate is closely related to gas temperature. The quantitative schlieren method has advantages of non-intrusive and continuously time-resolved properties, which has the potential in capturing the spatial-temporal evolution of gas temperature in leader channel. In this paper, a numerical model for the imaging process of quantitative schlieren system is established based on the ray theory of light. Aiming to design a quantitative schlieren system for the gas temperature of leader discharge in a 3 meters rod-plate gap, key parameters including temporal and spatial resolution that affect the measurement accuracy are simulated and the procedure to determine them is discussed. Finally, the simulated results are compared with measured ones, which verify the validation of the proposed design procedure.

Quantitative schlieren system simulation,leader dicharge,Spatial-temporal resolution