How to increase the Re number in a jet flow comput

Novice

Hi, i'm doing some DNS/LES computations of a jet flow. The code used a fourth order dinite difference scheme on a cartesian grid. Artificial non reflecting boundary conditions are used at all boundary. A velocity profile is prescribed at the inflow and the computations are started with the same condition in the whole domain. Density profile are also prescribed. Pressure is uniform and the flow is isothermal.

The non dimensionalization of the equations are made and several paremeters are to be specified, namely the Re number which depends on the nozzle exit diameter.

My question is, how to increase the re number of the computed flow? do i need simply to change the numerical value of the Re number i specify for the initialisations (keeping constant all the other values) or should i change also the diameter of the jet to increase the reynolds number? Thanks