Investigation of Air Flow Rates Effect in Presence of Heated Obstruction Within Room

摘要

This study reports the results of a numerical investigation of three-dimensional turbulent buoyant recirculating flow within rooms with heated obstruction. The study involves the solution of partial differential equations for the conservation of mass, momentum, energy, concentration, turbulent energy and its dissipation rate. These equations were solved together with algebraic expressions for the turbulent viscosity and heat diffusivity using k-ε turbulence model by performing simulations on FLUENT 6.3. The CFD method was validated via comparing with the available experimental data. A comparison with experimental results shows good agreement. This means that the present computer code has a good capability to simulate 3D airflow and effect of obstruction within room. The present study demonstrates the flow behavior, thermal distribution and CO_2 concentration inside the room in the presence of heat flux obstruction with respect to three values of volume airflow rate. The results show that the efficiency of ventilation (thermal) is less than one hundred percent and become more than one hundred percent when used low ventilation rate. Concentration of CO_2 is very often used as an indicator for the control of air flow rate to the building. The concentration of CO_2 is high above the obstruction in the occupation zone at low volume flow rate and it reduces with increase in the volume flow rate.