In combustion processes, optimization and numerical simulation of combustion of liquid fuels are very important. Considering complications of combustion process, one of the main problems in simulations of it, is time consuming calculations. Consequently one of the effective methods for optimizing these processes is to reduce time of calculations without accuracy changing. For this propose soft sensing methods are developed. One of these methods is Artificial Neural Network. In this research, particles equations in combustions flows, which their consumption fuel is light, have been solved by Artificial Neural Network. Then based on this algorithm we attempt to solve particles equations in Nano dimensions. At first, a computer code is developed in MATLAB software and a neural network is designed. Then number of neurons in hidden layer and number of layer is optimized. In the next step, using weights and biases of neural network a subprogram is written and this subprogram attached to main program. In final step, this program is used for three combustions, evaporation and isothermal cases and conclusions are discussed.