@article{ahmadi_cesarano_nawaz_ninos_bigham_2023, title={A high-performance lung-inspired ceramic 3D-printed heat exchanger for high-temperature energy-efficient systems}, volume={219}, ISSN={["1873-5606"]}, DOI={10.1016/j.applthermaleng.2022.119378}, abstractNote={The thermal-to-electric conversion efficiency of next-generation supercritical carbon dioxide and concentrated solar power plants is significantly augmented by operating at temperatures exceeding 1000 °C if durable, compact, high-temperature heat exchangers (HXs) are developed. Whereas metal 3D-printed HXs fail to operate under extreme temperature conditions, ceramic 3D-printed HXs are deemed promising candidates for high-temperature, highly oxidizing environments. Ceramic 3D-printed HXs, however, exhibit a high gas permeability issue through hot and cold separating walls due to an excessive non-volatile photopolymer content utilized. Here, a novel leak-free lung-inspired ceramic 3D-printed HX employing a highly complex heat transfer topology is introduced for high-temperature energy-efficient systems. The high permeability issue of ceramic 3D-printed HXs is fully eliminated through a uniform zinc-based coating. It was determined that the effective thermal conductivity of the sintered ceramic heat exchangers is affected by the coated layer. The high-temperature thermal and hydraulic characteristics of the lung-inspired ceramic 3D-printed HX are comprehensively examined and compared against a millichannel 3D-printed HX module. Experimental results indicated that the lung-inspired 3D-printed ceramic HX significantly outperforms its millichannel counterpart. The lung-inspired HX shows a volume-based power density of 8.2 MW/m3 at a hot-side inlet air temperature of 700 °C, a 71 % improvement compared with that of the millichannel HX. More importantly, the higher thermal duty of the lung-inspired 3D-printed HX is realized at a lower normalized pressure drop penalty of 510 Pa/W, 22 % lower than that of the millichannel ceramic HX. This study accelerates the advancement of high-performance ceramic 3D-printed HXs with complex topologies for high-temperature energy-efficient systems and/or corrosive environments.}, journal={APPLIED THERMAL ENGINEERING}, author={Ahmadi, Behzad and Cesarano, Joseph and Nawaz, Kashif and Ninos, Nikolas and Bigham, Sajjad}, year={2023}, month={Jan} }
 @article{fathi_heyhat_targhi_bigham_2023, title={Bifurcated divergent microchannel heat sinks for enhanced micro-electronic cooling}, volume={146}, ISSN={["1879-0178"]}, DOI={10.1016/j.icheatmasstransfer.2023.106868}, abstractNote={The thermal performance of microchannel heat sinks (MHSs) can be enhanced by utilizing extended surfaces such as pin fins, ribs, and bifurcation plates. Extended surfaces, however, adversely affect the hydraulic performance of the MHSs. Divergent microchannels, on the other hand, offer higher hydraulic performances but lower thermal performances than parallel microchannels. Here, bifurcated divergent MHSs are studied to examine the opposing effects of bifurcation and divergence on the thermo-hydraulic performance. Bifurcation plates with constant cross-section, variable width, and variable height are considered. Results showed that the pressure drop penalty and average heat transfer coefficient of bifurcated divergent MHSs are lower than the parallel MHSs. Considering the performance index (PI) defined as the ratio of heat transfer coefficient to pressure drop penalty, the bifurcated divergent microchannels outperform the parallel MHSs. Results also revealed that increasing the width of the bifurcation plate in the flow direction decreases the overall performance of the bifurcated divergent microchannels. The divergent bifurcation microchannels with a variable height bifurcation plate outperform the ones with a constant cross-section bifurcation plate. This study confirms the advantage of bifurcated divergent microchannels for increasing the cooling performance of the MHSs.}, journal={INTERNATIONAL COMMUNICATIONS IN HEAT AND MASS TRANSFER}, author={Fathi, Mostafa and Heyhat, Mohammad Mahdi and Targhi, Mohammad Zabetian and Bigham, Sajjad}, year={2023}, month={Jul} }
 @misc{mohammed_ahmadi_ma_bigham_2023, title={Desiccants enabling energy-efficient buildings: A review}, volume={183}, ISSN={["1879-0690"]}, DOI={10.1016/j.rser.2023.113418}, abstractNote={Buildings account for about 39% of the total energy consumption in the United States. Developing highly energy-efficient and environmentally friendly systems that are either actively or passively integrated into buildings plays a crucial role in decarbonizing the building sector. Among various technologies, desiccant-based energy systems have received particular attention in recent years due to their unique advantages, such as being thermally driven using low-grade waste or solar energies and being reliable over a wide range of operating ranges. Extensive research efforts have been exerted on desiccant-enabled technologies at both material and system levels aiming to increase their performance and achieve high technological readiness levels. The present review paper comprehensively discusses research works made at the system level. It overviews desiccant-based air conditioning systems, desiccant-based humidity pumps, desiccant-based thermal energy storage systems, and desiccant-based appliances. The study identifies challenges and opportunities to accelerate the commercialization of desiccant-enabled technologies. It is found that desiccant materials offer great promise to improve energy efficiency and functionality of future buildings through decoupling the latent and sensible cooling loads in air conditioning systems, humidity pumps integrated into building facades, and next-generation appliances. However, commercial viability and widespread acceptance of desiccant-based systems have been hampered by several major obstacles, including liquid and air flow mal-distribution and inferior thermo-physical properties of desiccant materials resulting in low ab/adsorption and regeneration rates and bulky/costly systems.}, journal={RENEWABLE & SUSTAINABLE ENERGY REVIEWS}, author={Mohammed, Ramy H. and Ahmadi, Masoud and Ma, Hongbin and Bigham, Sajjad}, year={2023}, month={Sep} }
 @article{fathi_heyhat_targhi_bigham_2023, title={Porous-fin microchannel heat sinks for future micro-electronics cooling}, volume={202}, ISSN={["1879-2189"]}, DOI={10.1016/j.ijheatmasstransfer.2022.123662}, abstractNote={Porous-fin microchannel heat sinks offering high solid-fluid interfacial areas have the potential to be an integral part of future microelectronic cooling systems. Replacing solid with porous fins reduces the pressure drop penalty of the straight plate-fin microchannel heat sinks. However, prior research has shown that in some cases porous fins adversely affect the thermal performance of the microchannel heat sinks. The reduced effective thermal conductivity of the porous fins compared to the solid ones has been considered the main reason for the reduced thermal performance of porous-fin microchannels. In this work, a detailed study is conducted to assess the feasibility of using porous fins to simultaneously improve the thermal and hydraulic performances of the straight plate-fin microchannel heat sinks. Results revealed that the porous-fin microchannels outperform the solid-fin microchannels at small channel heights. However, at high channel heights, the low effective thermal conductivity of porous fins results in a weak vertical thermal diffusion. Consequently, replacing solid with porous fins degrades the thermal performance of the microchannel at high channel heights. Additionally, the porous-fin microchannels exhibit better thermal performance than the solid-fin microchannels at fin to fluid width ratios above 0.25. The increased coolant mass flow penetrated the porous fin section is the main reason for the enhanced heat transfer rate of the porous-fin microchannels at higher width ratios. Moreover, the porous-fin microchannels offer a lower pressure drop penalty than the solid-fin microchannels under all examined operating conditions. This research confirms the potential of substituting solid with porous fins to simultaneously improve the thermal and hydraulic performances of the straight plate-fin microchannel heat sinks.}, journal={INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER}, author={Fathi, Mostafa and Heyhat, Mohammad Mahdi and Targhi, Mohammad Zabetian and Bigham, Sajjad}, year={2023}, month={Mar} }
 @misc{jafarinejad_hernandez_bigham_beckingham_2023, title={The Intertwined Renewable Energy-Water-Environment (REWE) Nexus Challenges and Opportunities: A Case Study of California}, volume={15}, ISSN={["2071-1050"]}, DOI={10.3390/su151310672}, abstractNote={In our built environment, societal production of energy and clean water is inextricably linked to the natural resources from which they are derived. Acknowledgement and consideration of the coupling of energy, water, and the environment (the energy–water–environment nexus) will be critical to a sustainable future. This is particularly true as we transition away from historical energy sources (e.g., coal, petroleum, natural gas) and into the widespread adaptation of renewable energy (RE) sources (e.g., solar, wind, geothermal, hydro, bioenergy) as a strategy to decrease greenhouse gas emissions and consequently slow global climate change. This transition is fraught with both challenges and opportunities at the county, state, national, and international levels, as addressing future societal needs with respect to energy and water, and the environment requires recognition of their interdependence and development of new technologies and societal practices. In this study, the focus is on the RE–water–environment (REWE) nexus. In California, the REWE nexus is becoming increasingly important in achieving 100% clean electricity from eligible RE and zero-carbon resources by 2045 and in the face of climate change and population and economic growth. In this context, California’s RE deployment and renewable electrical generation, its RE legislative information, REWE nexus, and intertwined REWE nexus challenges and opportunities in California (e.g., administrative–legal, technology development, digitalization, and end-of-life RE waste) are comprehensively discussed to identify the knowledge gaps in this nexus and solutions.}, number={13}, journal={SUSTAINABILITY}, author={Jafarinejad, Shahryar and Hernandez, Rebecca R. and Bigham, Sajjad and Beckingham, Bryan S.}, year={2023}, month={Jul} }