REVIEW PAPER Fuel atomization in gas turbines: A review of novel technology Amer Eid Salem Eid Thafnan Alajmi 1 | Nor Mariah Adam 1 | Abdul Aziz Hairuddin 1 | Luqman Chuah Abdullah 2 1 Department of Mechanical and Manufacturing Engineering, Universiti Putra Malaysia, Seri Kembangan, Malaysia 2 Department of Chemical and Environmental Engineering, Universiti Putra Malaysia, Seri Kembangan, Malaysia Correspondence Amer Eid Salem Eid Thafnan Alajmi, Department of Mechanical and Manufacturing Engineering, Universiti Putra Malaysia, Seri Kembangan, Malaysia. Email: amerq880@gmail.com Summary The atomization of fuel is crucial in the combustion and emission of a gas tur- bine, and the fuel atomization is continuous without any cycles or strokes. However, to achieve a desired amount of combustion during this continuous process, fuel must be added and mixed with the high‐pressure air exiting the compressor in proper proportions. To make the engine as small and light- weight as possible is a constraint and requires the fuel injection, mixing, and combustion to occur within the smallest volume possible. In most cases, this is inefficient and less practicable. A major drawback is the requirement of high injection pressure with relatively small increase in flow rate. In recent years, research was conducted to improve fuel atomization in a gas turbine by using different novel approaches that were simpler, more adaptable, and efficient to enhance the atomization. However, most of these studies were in isolation without any comprehensive literature on recent trends. Therefore, this review attempts to give an insight on recent development of fuel atomization in a gas turbine. Particular emphasis was given to air‐, plasma‐, ultrasound‐, and supercritical fluid–assisted atomization techniques. KEYWORDS air‐assisted atomization, combustion, fuel atomization, gas turbines, novel technology, plasma‐ assisted atomization, supercritical fluid–assisted atomization, ultrasound‐assisted atomization 1 | INTRODUCTION Gas turbines are internal combustion engines that are used to generate electricity. A gas turbine consists of an upstream revolving compressor coupled with a down- stream turbine and a combustion chamber. 1 All gas turbines generate thrust by providing a change in momentum to the air that enters and leaves the gas tur- bine. 2-4 The higher the difference in momentum, the greater the thrust that the gas turbine produces. 5 Liquid fuel in the combustor is burnt in large gas tur- bine engines, and it is usually pressure‐atomized with a high‐pressure fuel pump. 6 It is essential to know here that due to reduction in engine dimensions, the high‐ pressure fuel pump does not level with the engine in terms of size or weight; hence, pressure atomization is considered to be detrimental and damaging in small gas turbines that are usually applied in cruise missiles, smart miniature munition systems, business jets, unmanned aerial vehicles, and a number of other turbine engine applications. 6-8 Simultaneously, small turbine engines can function appropriately at higher rotation rates that might approach 100 000 rpm, and this permits the utiliza- tion of rotary centrifugal atomizers so as to work as the fuel spray, substituting the high‐pressure fuel pump. In a way, this technique is beneficial and cost‐effective, Received: 10 August 2018 Revised: 10 December 2018 Accepted: 20 December 2018 DOI: 10.1002/er.4415 Int J Energy Res. 2019;1–16. © 2019 John Wiley & Sons, Ltd. wileyonlinelibrary.com/journal/er 1