Journal of Advanced Research in Fluid Mechanics and Thermal Sciences 45, Issue 1 (2018) 73-81 73 Journal of Advanced Research in Fluid Mechanics and Thermal Sciences Journal homepage: www.akademiabaru.com/arfmts.html ISSN: 2289-7879 Impact of Gasoline RON on Engine Vibration, Knock and Sound Level in a Single-Cylinder SI Engine Heoy Geok How 1,* , Yew Heng Teoh 2 , Kok Hwa Yu 2 , Hun Guan Chuah 1 , Kai Wen Samson Lim 1 1 Department of Engineering, School of Engineering, Computing and Built Environment, KDU Penang University College, 32, Jalan Anson, 10400 Georgetown, Penang, Malaysia 2 School of Mechanical Engineering, Universiti Sains Malaysia, Engineering Campus, 14300 Nibong Tebal, Penang, Malaysia ARTICLE INFO ABSTRACT Article history: Received 20 April 2018 Received in revised form 15 May 2018 Accepted 16 May 2018 Available online 17 May 2018 Engine vibration is critical toward overall engine performance, engine lifespan and passenger comfort. Engine sound level is critical toward the environment by increasing the noise polution. An experimental investigation on cylinder block vibration of engine, knock intensity and sound level with research octane number (RON) 95, 97 and 100 was carried out on a spark ignition (SI) engine under different engine speeds (1600, 2000, 2400, 2800 and 3200 RPM). The experiment was conducted in a proper experimental setup with all the equipment and materials. Multiple sensors were used in this experiment to obtain the following data such as accelerometer sensor, knock sensor and microphone. This experiment proved that cylinder block vibration and knock intensity with RON 100 had the lowest reading data compare to RON 95 and RON 97. The sound level (Pa) for RON 100 is the highest compared with RON 95 and RON 97 due to this fuel is able to produce more power and this affected the sound level of RON 100. In conclusion, RON 100 is better in every aspect and suitable for car’s engine which are able to draw out all the fuel performance. Keywords: Vibration, RON, knock Copyright © 2018 PENERBIT AKADEMIA BARU - All rights reserved 1. Introduction Vehicles are mobile bodies that carry and transport people or goods. There are few categories for vehicles such submarines, space vehicles, trains, airplanes, and others. Every vehicle that moves on the road will have an engine build into it. Once the engine starts to operate, it will create sound and movements in the whole vehicle. Vibration is the vehicle’s engine in operation and the vehicle or a part of it perform oscillatory motion [1, 2]. The sound is the adjacent air which exhibits vibration. An operating engine will produce a pinging or knocking sound. This process is called engine knocking. Vehicle sound includes wanted and unwanted sounds. Therefore, the unwanted sound is noise. Vibration and noise can affect passenger discomfort and can be harmful to the customer’s perception of vehicle quality [3]. Comfort of riding, driving stability and drivability are important factors in the performance of a vehicle and are affected by the engine vibrations [4, 5]. Vibration and sound quality * Corresponding author. E-mail address: heoygeok@gmail.com (Heoy Geok How) Penerbit Akademia Baru Open Access