Units of forces and average kinetic energy

For the example code generalExternalFlow, I wanted to know what the units of forces on surface and the average kinetic energy are. If I give all the inputs in SI units, are these in Newton and Joule respectively?

I am performing a large eddy simulation. Also, instead of manually specifying the time step, I use:

uMaxLb = 0.1;
Re = 5000; //Reynolds number
uMaxPhys = //maximum velocity in the fluid due to the moving object
dt = dx * uMaxLb / uMaxPhys;
T nu_LB = resolution * uMaxLb / Re;

The velocity in the external domain is zero.
The problem is if I increase the value of Reynolds number and reduce grid size even by small amounts, I see a significant change in the output forces and kinetic energy. Is this normal? what is the reason for this?