ANALISIS AERODINAMIKA KENDARAAN TIPE URBAN SRIWIJAYA ECO DENGAN METODE COMPUTATIONAL FLUID DYNAMICS (CFD)

Kontes Mobil Hemat Energi (KMHE) is an annual competition in the automotive prototype and urban concept categories. Participants must design, build, and compete for unique vehicles that can achieve maximum fuel efficiency in this event. Regulatory standards are the primary reference in designing vehicle models that will take part in the competition. Sriwijaya University has a Semi-Autonomous Body engaged in automotive research, namely Sriwijaya Eco. The Sriwijaya Eco team has participated in an annual international competition called the Shell Eco-Marathon (SEM) in the battery-electric prototype concept category. However, for the urban class, the new Sriwijaya Eco concept has competed on a national scale, namely Kontes Mobil Hemat Energi (KMHE) from the first year participating in the competition, Sriwijaya Eco has never gotten the best results, this is caused by various factors including the aerodynamic analysis factor that not maximized. Therefore, an aerodynamic analysis was carried out on the Sriwijaya Eco urban concept vehicle in this scientific research paper by following Kontes Mobil Hemat Energi (KMHE).This study aims to determine the characteristics of the airflow around the vehicle body and get the coefficient of drag from the Sriwijaya Eco urban. Thus, further development of the body design can be carried out to reduce the drag that occurs on the vehicle surface. The tools used in this research are a laptop (MSI GF63 Thin 9RCX) and two pieces of software, namely Solidworks 2020 and ANSYS 2020 R1. The simulation process begins with modeling the solid-body urban Sriwijaya Eco vehicle. If it complies with regulatory standards, it will import the solid body's geometry into ANSYS Spaceclaim to create a simulation domain. After that, the following process is to set up the input parameters to be simulated. When finished doing the simulation, the results obtained at a speed of 20 km/h the coefficient of drag is 0.3971, and the coefficient of lift is 0.7658, while at a rate of 40 km/h, the coefficient of drag is 0.3888, and the coefficient of lift is 0.732. The aerodynamic simulation of the Sriwijaya Eco urban vehicle made modifications to the body design to get a smaller cd value. The modification process was carried out once and called a coefficient of drag value of 0.1502 (Revision 1) at a speed of 20 km/h and 0.1392 (Revision 1) at a rate of 40 km/h. At the same time, the coefficient of lift is 0.0048 (Revision 1) at a speed of 20 km/h and -0.015 (Revision 1) at a rate of 40 km/h. So it can conclude that the smallest coefficient of drag is found in the Sriwijaya Eco Revision one urban modification design and can still be developed the Sriwijaya Eco urban body design further.