Volume I - Section IV - Experimental Work and Verification of CFD Methodology 
Page IV - 1 
4. EXPERIMENTAL WORK AND VERIFICATION OF 
CFD 
METHODOLOGY 
4.1 
Experimental Work 
4.1.1 
Cage Condition 
4.1. 1.1 
Objective 
Several series of experimental scenarios were defined to consider a known mouse cage placed in 
a wind tunnel. The primary objective of the experimental measurements was to create and 
measure various airflow s within the mouse cage in such a manner as to lay the ground work for 
determining the boundary conditions for the computational fluid dynamics (CFD) analysis of the 
cage. In particular, a series of CFD models were constructed to simulate the cage wind tunnel 
experiments. The primary reason for the validation of the CFD model of the cage against 
experimental data were to obtain an appropriate set of boundary conditions to represent the cage 
in the whole room simulations. The two sets of boundary conditions that are of most concern are 
those associated with the transfer mechanisms into and out of the cage, namely the side cracks 
and the top of the cage, that includes the filter media. 
4.1. 1.2 Experimental Apparatus 
The apparatus used in this series of experimental scenarios was kept relatively constant 
throughout, with the main difference being the representation of the mice within the cage. 
The wind tunnel cross section was 0.40 m x 0.50 m (15.75" wide x 20" deep). It was 1.72m (68") 
long with a 0.80m (32") long test section in the center. Room air entered the wind tunnel through 
a furnace filter (0.41m x 0.50m x 2.5e-2m (16” x 20” x 1”); American Air Filter, Louisville, KY) 
then passed through three perforated metal screens (60 percent, 40 percent, then 33 percent open 
area) that acted as a settling means so airflow approaching the test section was uniform. The inlet 
filter was placed 0.10 m (4") from the end of the wind tunnel and the outlet filter was 0.43 m 
(17") from the other end. The first metal screen was 0.10m (4") from the inlet filter and the 
screens were spaced 0.10 m (4") apart. Detailed drawings of the wind tunnel are presented in the 
figures 4.01 to 4.03, while a picture of the wind tunnel with the cage in the parallel orientation is 
shown in figure 4.04. 
The instrumented mouse cage was made from a standard Lab Products, Inc., shoebox mouse 
cage with approximate top dimensions of 0.18m x 0.28m x 0.13 m (7" wide x 11" long x 5" high) 
(see figures 4.05 to 4.1 1). The filter top was the high profile type and the filter was a Reemay 
#2024, 2.1 oz/yd 2 , 12 mils thick. The cage had approximately 1.25e-2m (0.5") of hardwood 
shavings bedding on the floor, a wire rack, water bottle, and simulated feed. 
