Saad A. Jajja

My background is in traditional thermal-fluid sciences with a focus on empirical heat transfer characterization of different working fluids. My doctoral work was focused on experimental and analytical characterization of turbulent heat transfer of supercritical carbon dioxide in the proximity of the pseudo-critical point. At ORNL, my work is focused on the following topics:

1. High frequency transient heat load thermal management
2. Multiphase heat and mass transport fundamentals in emerging refrigerants.
3. Thermal-hydraulic characterization of ceramic heat exchangers for high temperature (~ 800 C ) applications.

In addition to the above core expertise areas, I have experience in conducting thermodynamic analysis (1st and 2nd Law) for various energy conversion systems. This allows me to identify areas/components which require research attention.

My representative publications are as follows:

1. Jajja, S.A., Nawaz, Kashif, and Fricke, B.A (2022), “In Tube Condensation Heat Transfer and Pressure Drop for R454B andR32 – Potential Replacements for R410A” , International Journal of Refrigeration, doi.org/10.1016/j.ijrefrig.2022.07.019
2. Jajja, S.A., Randle, Lindsey, and Fronk, B.M (2022), “A Modeling Approach to Account for Unstable Stratification, Flow Acceleration, and Variable Thermophysical Properties for Supercritical Carbon Dioxide”, International Journal of Heat and Mass Transfer, 187, 122537.
3. Jajja, S.A. and Fronk, B.M (2021), “Investigation of Near-Critical Heat Transfer in Rectangular Microchannels with Single Wall Heating Using Infrared Thermography”, International Journal of Heat and Mass Transfer,177, 121470.
4. Jajja, S.A., Sequeira, J.M, Fronk, B.M (2020), “Geometry and Orientation Effects in Non-Uniformly Heated Microchannel Heat Exchangers Using Supercritical Carbon Dioxide”, Experimental Thermal and Fluid Science, 112. DOI: doi.org/10.1016/j.expthermflusci.2019.109979
5. Jajja, S. A., Zada, K. R., Fronk, B. M. (2019), “Experimental Investigation of Supercritical Carbon Dioxide in Horizontal Microchannels with Non-Uniform Heat Flux Boundary Conditions”, International Journal of Heat and Mass Transfer, 130, pp 304-319. DOI: doi.org/10.1016/j.ijheatmasstransfer.2018.10.02

Awards:

     1. Awarded the School of Mechanical Industrial and Manufacturing Engineering Teaching Fellowship at Oregon State University (2019).
     2. Awarded the Fulbright Scholarship by the J. William Fulbright Foreign Scholarship Board (FFSB) (2014 – 2016).
     3. Best Undergraduate Senior thesis of the year 2013 at University of Engineering
         and Technology Taxila, Pakistan (2013).

Projects Led:

Thus far, I have successfully secured funding and led the following projects as a PI:

1. Increasing GPU Reliability by Predicting and Damping High Frequency Thermal Oscillations (ORNL LDRD Seed Grant – $240K)
2. Increasing the Condensate Recovery in ORNL Steam Plant to Reduce Primary Fuel Consumption and the Associated Emissions (Sustainable ORNL Initiative – $150K)