Experimental study of some parameters to enhance efficiency of evaporative cooler: Technical notes

Furqan Haider Mohammed Ali, Zahraa Haider Mohammed Ali, Mustafa Naozad Taifor , Hussein Hayder Mohammed Ali
Abstract

As an alternative to conventional vapour-compression air conditioning systems, which significantly increase peak electrical demand and energy consumption, this study investigates methods to enhance the performance and energy efficiency of evaporative cooling systems. A hybrid dual cooling configuration integrating a vapour-compression refrigeration unit with an evaporative cooler was experimentally developed and evaluated. The study focused on key modifications, including the replacement of conventional wood dust pads with padding cartoon material, the use of an auxiliary submersible pump to increase water circulation, and the combined operation of both pad materials. The experimental results demonstrated a substantial improvement in system performance due to these modifications. In particular, the hybrid system operating with a combined wood dust and padding cartoon medium achieved the highest cooling efficiency of 89%, indicating a significant enhancement in heat and mass transfer processes. The integration of increased water flow further contributed to improved wettability of the pads and more effective evaporative cooling. In terms of energy performance, the hybrid system exhibited an energy efficiency ratio (EER) of 8.3, which is markedly higher than that of the standalone vapour-compression system (EER = 1.95). Additionally, the independent evaporative cooling system achieved a maximum EER of 14.8 with a cooling efficiency of 71%, confirming its superior energy-saving potential under suitable operating conditions. The results also revealed that optimising pad material characteristics and water distribution plays a critical role in enhancing cooling efficiency while minimising energy input. These findings confirmed that the integration of evaporative cooling with conventional systems, along with appropriate material selection and hydraulic enhancement, can significantly reduce overall energy consumption while maintaining satisfactory thermal comfort levels. From a practical perspective, the proposed hybrid cooling system is a cost-effective, energy-efficient, and sustainable solution for hot, dry climates, utilising low-cost local materials and simple modifications to reduce energy demand and emissions while improving and guiding future cooling technologies

Keywords

hybrid air conditioning; thermodynamic analysis; wood dust; cardboard padding; energy efficiency

Suggested citation
Ali, F.H.M. , Ali, Z.H.M. , Taifor , M.N. , & Ali, H.H.M. (2026). Experimental study of some parameters to enhance efficiency of evaporative cooler: Technical notes. Machinery & Energetics, 17(1), 73-81. https://doi.org/10.31548/machinery/1.2026.73
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