Hi Alia, please, see my following papers (available on research gate):

Srebric, J. and Chen, Q. 2002. "An Example of Verification, Validation, and Reporting of Indoor Environment CFD Analyses," ASHRAE Transactions, 108(2): 185-194.

Srebric, J. and Chen, Q. 2002. "Simplified Numerical Models for Complex Air Supply Diffusers," Int. J. of HVAC&R Research, 8(3): 277-294.

Srebric, J. and Chen, Q. 2001. "A Method of Test to Obtain Diffuser Data for CFD Modeling of Room Airflow," ASHRAE Transactions, 107(2): 108-116.

Srebric, J., Chen, Q., and Glicksman, L.R. 1999. "Validation of a Zero-equation Turbulence Model for Complex Indoor Airflows," ASHRAE Transactions, 105(2): 414-427.

All my papers work with stead-state condition in an environmental chamber (similar to a single room). If you indoor thermal conditions are not dramatically changing with time, you can assume quasi steady-state conditions, so you can work with averaged values of measured parameters. I hope this helps. I'll be happy to answer follow up questions, if you any.

Good luck with your work, Jelena Srebric

Thank you very much Dr Jelena...the papers were very useful, especially the first one.

i really appreciate it 

Alia

Hi Alia

if you want to measure very low velocity you read the following article

Lorenzini, G. 2006. Experimental Analysis of the air flow field over a hot flat plate.

International Journal of Thermal Science. 45: 774 - 781.

It is very hard to validate reading when you have very low velocity.