[benqing]

hi everybody

Recently ，I have simulationed square duct flow with new turbulence model ，but there are some problem.
the BC in x direction is cyclic ， in yz direction is wall ，it’s very simple. And there is a fixed mean flow velocity in x direction，using pressureGradientExplicitSource in fvoption ,the pressure gradient is calculated automatically
first，the result is reasonable when i run the case with RANS model,

pressure gradient = 0.179097

but pressure gradient become very small when i run the case with new turbulence model

pressure gradient = 0.0903267

the new turbulence model has already been verified in case of channel395，but in present case the pressure gradient pressure gradient ， could anyone help me ？
benqing