emergency:reference values in Fluent

avesta

Dear all All books on heat transfer tell me the Nusselt number of the fully-developed laminar flow in a pipes is a constant;if the wall temperature is constant,the Nu=3.66;if the heat flux is constant,the Nu will be 4.36. but when i simulate this ,Nu in constant wall temperature will be 2.59 and it do not limit to 3.66 in fully developed laminar flow. i do not know what reference values put in meno of reference valuen in report>reference values...

what reference values do you recommand?

i want to simulate laminar flow in a pipe as non-dimentional by Fluent.

inflow: U=1,T=1 WALL: U=0, T=1

Density=1, Cp=1, Thermal Conductivity(K)=1/(Re.Pr), Viscosity=1/Re

guide me

best regard

Avesta