Hollow nanofibers have received a lot of attention due to their applications. One of the methods of producing hollow nanofibers is the use of coaxial electrospinning method, which is both faster and more economical than other methods of producing nanofibers. In the production of hollow nanofibers using coaxial needles, a solution of both internal and external needles is usually used soultion, and the nanofibers are spun in this way, and later, during operations, the core phase is emptied and hollow nanofibers are formed. In the present study, air has been used as the core of the fluid to produce nanofibers in one step and more economically. External fluid glycerol was used to study the electrospinning parameters in the formation of hollow nanofibers. In this case, it was not possible to produce nanofibers due to the nature of glycerol, but the focus of the present work is on the formation of the smallest possible bubble due to the study of electrospinning parameters. In the laboratory experiments section of the present work, a coaxial needle and a frame for coaxial needle placement were designed and manufactured. Next, the coaxial electrospinning phenomenon was photographed by a high-speed camera and image processing was used for greater image resolution. The effective parameters of the shell solution in the electrospinning process such as viscosity and surface tension and the effective parameters of the device such as changing the diameter of the inner needle, changing the diameter of the electrode used and changing the distance of the inner needle from the outer needle and their effect on the bubble diameter are discussed. By changing the viscosity, it was observed that at lower voltages, the higher viscosity of the glycerol solution reduces the bubble diameter. By reducing the surface tension of the glycerol solution, it was observed that the solution with higher surface tension causes bubbles with a larger diameter. The change in the diameter of the inner needle was also examined and it was observed that the smaller the diameter of the inner needle causes the smaller the diameter of the bubble. By changing the diameter of the ring electrode, it was observed that by keeping the outer diameter of the ring electrode constant and using a ring electrode with a smaller inner diameter, the bubble diameter decreases. By changing the distance of the inner needle from the outer needle head, it was observed that when the inner needle is located at a distance farther from the outer needle head, a bubble with a smaller diameter is produced. At the end, the results of the present work will be summarized and suggestions will be given for the development and continuation of the present work. Keywords: Nanofiber, Electrospinning, Coaxial needle, Viscosity, Surface tension, Core phase fluid, Bubble