Date of Award

Fall 2017

Document Type


Degree Name

Doctor of Philosophy in Mechanical Engineering - (Ph.D.)


Mechanical and Industrial Engineering

First Advisor

Chao Zhu

Second Advisor

Zhiming Ji

Third Advisor

Chao-Hsin Lin

Fourth Advisor

I. Joga Rao

Fifth Advisor

Eon Soo Lee


Expiratory droplets from human coughing in an air-conditioned environment have always been considered to be potential carriers of pathogens, responsible for respiratory disease transmission. The air movement/circulation and ambient conditions such as pressure and temperature are all key factors of aerosol transport. To study the transmission of disease by human coughing in a depressurized air-conditioned chamber, there are many technical challenges, including the following: 1) the study of simulating human coughing; 2) the collection of aerosol generated by coughing; 3) the CFD simulation of coughing-induced aerosol transport in an air-conditioned chamber; 4) the validation of such a CFD simulation by experiment; 5) the depressurization of the air-conditioned chamber and 6) the mechanistic study of droplet evaporation. Accordingly, this work provides the following to study the aerosol transmission in a depressurized chamber: a transient repeatable bimodal cough simulator is designed and built; a chamber with air-conditioning and circulation is built; a breathing simulator is designed and built as well as measurement validation is done; a full field three dimensional CFD simulation of the aerosol transport in the air-conditioned chamber is established; a droplet evaporation model is built as well as the technology of depressurization for an open flow system.