## 1 _Article_
###### Abstract  
Plasma stimulation is a form of waterless fracturing as it requires that only the wellbore be filled with an aqueous fluid. The technique creates multiple fractures propagating in different directions around the wellbore. The intent of this paper is to present an experimental and numerical investigation of the degree of competitiveness of plasma stimulation with hydraulic fracturing, especially in the case of stimulating tight formation. Several cases were run experimentally. The samples included limestone and sandstone to investigate plasma fracturing in different rock types. In addition, the main goal of the experiments was to study the creation of fracture(s) under confining stresses, the type of rock, the amount of electrical energy used in the experiment, and the length of the wire to generate the plasma reaction. A laboratory plasma equipment was designed and used to accomplish the experimental work. The experiments were then numerically matched using a finite element numerical simulator, HOSS developed by LANL (Los Alamos National Lab). HOSS was developed to simulate high-strain-rate fractures such as those created by plasma stimulation. It accounts for mixed-mode fracture mechanics which are tensile and shear fractures. The simulator governing equations obey the conservation of mass and momentum in a solid-mechanics sense and account for the nonlinear deformation of rock material. The matching of the experiment allowed us to validate the HOSS simulation of the process and showed that the numerical results are in good agreement with the experimental work. Using the HOSS simulator, we also investigated the effect of higher energy levels and/or short release time on a cement rock model. The pressure profile that is developed due to the energy release can vary in the peak pressure and the release time. The results showed that the plasma fracturing technique is an effective stimulation method in sandstone and limestone. Plasma fractures were developed in the rock samples and extended from the sample wellbore to the outer boundaries. The shape of the pressure pulse has an impact on the developed fractures. Moreover, the effect of plasma stimulation on natural fractures was studied numerically. It was found that natural fractures can arrest the plasma-generated fractures that propagate from the wellbore to the outer boundaries. However, new fractures may develop in the rock starting from the natural fracture tips. waterless stimulation; plasma fracturing; experimental study; numerical simulation 2024202024144752024147  
[PERSON] et al. [2] presented a simulation study on the pulsed fractures and a comparison to experimental work. The paper discussed the propagation of plasma features under multiple shockwaves, the effect of outer boundary conditions on the extension of the fractures, and the influence the wellbore casing has on the plasma stimulation process. They found that an efficient fracture network can be developed by an optimized sequence of repetitive shockwaves in the same wellbore. Because of the extremely high pressure generated inside the wellbore relative to the formation stresses, it has been observed that stress anisotropy has a minor impact on the propagation of the fractures. However, the value of confining stresses has a major impact on the length of the developed fractures. They reported a case where 5 MPa of stress isotropy reduced the fractures length to one-third of the length that developed under unconfined conditions. [PERSON] et al. [3] presented experimental and numerical examples of plasma stimulation. They studied the effect of several parameters, including the effect of wire, input energy, confining stress, and rock type on the induced fractures. Measurement of the permeability around the plasma fractures showed that the plasma stimulation increased the rock permeability by more than one or two orders of magnitude. A numerical investigation of the effects of the stimulation technique on production was presented. [PERSON] et al.