College of

Engineering, Architecture and Technology

 

Meet Amjid Khan! Amjid is a 2^nd year PhD student, set to graduate in the Fall of 2025. Amjid enjoys savoring good food, though he will tell you he is not the biggest fan of preparing it. When he has free time at home, you can find him viewing a movie, a Cricket game, or engrossed in a book. Two books that he returns to the most are The Alchemist by Paulo Coelho and The Idea of Pakistan by Stephen P. Cohen.

 

Amjid did an internship at Oregon State University as part of an exchange program while completing his master’s degree. At the time, he was studying the aerodynamic side of compressors, and found himself intrigued by the thermal side of compressor research. He went to his professor, stating he would like to do his PhD in this area. Amjid was recommended to Dr. Bradshaw through a connection his professor had, and now Amjid is an integral part of CIBS, as well as working on other sponsored projects.

For environmental concerns, there is a notable shift towards the adoption of heat pump technology in the HVAC industry. This transition necessitates a deeper understanding of injected compressor technologies, particularly for cold climate heat pumps, which exhibit superior efficiency in extreme weather conditions compared to traditional technologies.

 

Having built a flammable fluids compressor load stand to test 3–10-ton compressors, Amjid is currently collecting experimental data for how flammable refrigerants behave in different vapor-injected compressor technologies. The end goal of this data collection is to develop a high fidelity semi-empirical and refrigerant flexible vapor-injected compressor model. This project is jointly sponsored by Rheem Manufacturing and CIBS. Currently, the load stand is manually controlled, which is a time-consuming process, taking approximately 6-7 hours to gather a single data point. Considering that over 30 data points need to be collected for each compressor, an additional objective of the project is to automate the load stand, thereby incorporating technological advancements.

 

A widely used technique for assessing compressor performance is the 10-coefficient AHRI empirical model. Amjid's black-box vapor-injected compressor model, on the other hand, only requires 6 data points to accurately predict compressor performance. This streamlined approach significantly reduces the time required for evaluating compressor performance and is expected to benefit industrial members of CIBS by minimizing the number of experimental data points needed.

 

His recent publication focuses on comparing the performance of vapor compression cycles using different methods of compressor flooding (Khan and Bradshaw (2022)). The paper presents a quantitative analysis of the performance of these cycles and discusses the findings in relation to compressor flooding techniques. One of Amjid's journal papers is currently under review focusing on different injected compression systems (Khan and Bradshaw (2023)). Additionally, Amjid Khan has two papers that have been accepted for publication in the 13th International Conference on Compressors and their Systems scheduled in September in City, University of London. One of the papers accepted is on development of a residential scale compressor load stand to measure compressor performance using environmentally friendly refrigerants (Khan and Bradshaw 2023)), while the other analyzes the potential of using R454B as a low-GWP alternative to R410A in a vapor-injected compressors (Khan et al. (2023)).

 

In the future, Amjid would like to do experimental work for the entirety of the systems he works with, rather than just one part of the system. Longer-term, Amjid aims to engage in industry research, aspiring to eventually become a professor. He compared the workloads of professors in the US and Pakistan, highlighting the dedication and availability of his US professors, which at first seemed daunting, but now he believes he can someday have success as a professor.