1. A system for optimizing and controlling properties of nanoparticles, wherein the properties comprises a mean particle size and a specific surface area of the nanoparticles for a scale up of nanoparticle production, the system comprises: an aerosol flame reactor; process instruments; a memory; and a processor coupled to the flame reactor and to the process instruments, the processor executes programmed instructions stored in the memory for performing the steps of: determining a) operating data for physical process parameters of a precursor or a reactant from the process instruments; b) mixing characteristics of the precursor or the reactant at a particular concentration and a stream input fed to a burner of the aerosol flame reactor; c) a flame temperature, different species mass-fractions, particle size and specific surface area throughout the aerosol flame reactor using a flame dynamics model coupled to a continuous particle population balance model, wherein the coupling between the flame dynamics model and the continuous particle population balance model is achieved by solving particle population balance equations in each and every cell of a computational domain using the outputs from flame dynamics model; d) data for showing influence of the burner and a design of the aerosol flame reactor on the properties of the nanoparticles; feeding the operating data, burner design parameters, a burner configuration, properties data; physical process parameters to a simulation tool with programmed instructions to obtain simulated flame dynamics data; feeding the simulated flame dynamics data from flame dynamics model to the continuous population balance model to obtain the mean particle size and the specific surface area of the nanoparticles by the solving particle population balance equations in each and every cell of the computational domain; and processing the mean particle size and the specific surface area of the nanoparticles for optimizing and controlling the mean particle size and the specific surface area and for scale up of the nanoparticle production in the aerosol flame reactor by dynamically changing any one or more of the operating data, the burner design parameters and/or the burner configuration.