Lung cancer respiratory gas detection system based on Porphyrin sensor arrays（PSAs）is used to detect human respiratory gases qualitatively through the acquisition and processing the information of PSA images

to achieve the purpose of early lung cancer diagnosis.In the detection process

whether PSA chips can bind gas molecules rapidly and uniformly

directly affects the accuracy of detection system.The chamber in which PSA chips reacts with lung cancer respiratory gases as the research object

is produced physically on the basis of the gas theoretical model with FLUENT which is a kind of CFD special software

simulating the gas chamber flow filed and optimizing its structure.The results show that the gas chamber using the optimization options of parabolic chamber cavity

installation of guide plates

reducing the diameter of diversion holes and increasing the tilt angle of diversion holes appropriately

in which the respiratory gases show a laminar flow state and the flow field is more uniform and dense

can achieve the requirements of PSA chips binding with gas molecules rapidly and uniformly.