Continuous need for the optimum conversion efficiency of polymer electrolyte membrane fuel cell (PEMFC) operation has triggered varieties of advancements, namely in the thermal management engineering scope. Excellent heat dissipation is correlated with higher performance of a fuel cell, thus increasing its conversion efficiency. This study reveals the potential advancement in thermal engineering of a fuel cell cooling system with respect to nanofluid technology. Nanofluids are seen as a potential evolution of nanotechnology hybridization with the fuel cell serving as a cooling medium. The available literature on the thermophysical properties of potential nanofluids, especially on the electrical conductivity property, has been discussed. The lack of electrical conductivity data for various nanofluids in open literature was another challenge in the application of nanofluids in fuel cells. Unlike in any other thermal management system, a nanofluid in a fuel cell is dealt with using a thermoelectrically active environment. The main challenge in nanofluid adoption in fuel cells was the formulation of a suitable nanofluid coolant with heat transfer enhancement, as compared to its base fluid, but still complying with the strict limits of electrical conductivity as low as 2 S/cm and several other restrictions discussed by the researchers. It is concluded that a nanofluid in PEMFC is advantageous in terms of both heat transfer and simplification of the cooling system through radiator size reduction and potential elimination of the deionizer as compared to the current PEMFC cooling system. However, there are challenges that need to be well addressed, especially in the electrical conductivity requirement.

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Improving fuel consumption with lower exhaust emissions give more focused to all car manufactures. A higher engine performance with lower exhaust emissions requires a complete mixing process resulted in ultra-lean high combustion efficiency. Air intake temperature is one of the alternative strategies to improve fuel consumption and reduced exhaust emissions. This is due to the cold air is denser and contain higher oxygen availability. Air intake temperature will affect to the oxygen concentration in the charged air that influence the combustion process through ignition delay and fuel burning rate. The objective of this experiment is to investigate the effects of air intake temperature to the fuel consumption and exhaust emission at variation of engine speeds and constant load by using 1.6L gasoline engine. Air intake temperature was changed from 20 °C to 30 °C. The DaTAQ Pro V2 software was used to measure the engine fuel consumption while gas analyzer (MRU Gas Analyzer) was used to measure the exhaust emission such as Unburned hydrocarbons (UHCs) and carbon monoxide (CO). The results showed that fuel consumption, UHCs and CO emissions increased with the increase of air intake temperature. The increase of air intake temperature resulted in advanced and shorter combustion duration. Higher oxygen concentration at lower air intake temperature leads to the complete mixing process and complete combustion.  Therefore, the experimental results can be concluded that the lower air intake temperature resulted in improved fuel consumption and reduced UHCs and CO emissions.

Nanofluid is an emerging technology in heat transfer study. The effect of nanofluids as a cooling medium in liquid cooled Proton Exchange Membrane Fuel Cell (PEMFC) is studied. Nanofluids with 0.1% and 0.5% volume concentration of Al2O3 are dispersed in base fluid of 50:50 mixture of Ethylene Glycol and water were analyzed experimentally. A rated power of 400 W liquid cooled PEMFC was used to verify the findings. The result showed that insignificant improvement in performance of PEMFC with nanofluids through polarization curve findings, perhaps due to the lower wattage of PEMFC used. The advantage of nanofluids utilization in PEMFC might be visible in higher wattage of PEMFC due to higher working fluid temperature. Higher thermal conductivity of nanofluid at higher temperature is expected to give advantage in terms of polarization curve of a PEMFC. However, the thermal performance is improved through the heat transfer rate increment of 68.5 % and 46 % for both 0.5 % of Al 2 O 3 nanofluid and 0.1 % of Al 2 O 3 nanofluid respectively.

Nanofluid is an emerging technology in heat transfer study. The effect of nanofluids as a cooling medium in Proton Exchange Membrane Fuel Cell (PEMFC) is studied. Nanofluids with 0.1% and 0.5% of Al2O3 dispersed in base fluid of 50:50 mixture of Ethylene Glycol and water were analyzed experimentally. A 400 W liquid cooled PEMFC was used to verify the findings. The result showed that insignificant improvement in performance of PEMFC with nanofluids, perhaps due to the lower wattage of PEMFC used. However, the thermal performance is improved through the heat transfer rate increment of 68.5 % and 46 % for both 0.5 % of Al2O3 nanofluid and 0.1 % of Al2O3 nanofluid respectively.