Journal of Scientific & Industrial Research Vol. 78, July 2019, pp. 466-472 Designing of a Carburettor Body for Ethanol Blended Fuel by using CFD Analysis tool and 3D Scanning Technology P Gupta 1 , A Haleem 2 and M Javaid 3 * < 1 Mechanical Engineering, Jamia Millia Islamia, New Delhi 2, 3 Department of Mechanical Engineering, Jamia Millia Islamia, New Delhi Received 29 December 2017; revised 15 October 2018; accepted 15 March 2019 Carburettor plays a significant role in mixing air and fuel during suction for spark ignition (SI) engines. Some important factors which can affect the fuel consumption are design of carburettor, throttle valve angle and its position as well as the composition of ethanol in gasoline. Nowadays the carburettor is used only for bikes/motorcycles/generators. The design of carburettor is essential in maintaining the correct air-fuel ratio during running conditions. So, the carburettor design is improved in such a way that it can optimize the required air-fuel ratio by considering the current atmospheric temperature, mixing ethanol in high proportion with gasoline fuel to reduce the adverse effects on the environment. The purpose of this paper is to study the effects of throttle plate angle and its position on the volumetric efficiency of the engine and the impact on mass flow rate, pressure variation and temperature by mixing ethanol in fuel. Scanning of a working carburettor is done through COMET L3D Scanner and modelled it in SOLIDWORKS software by installing two throttle plates at the outlet of the carburettor venturi. Analysis of computational fluid dynamics for variation in mass flow rate and pressure distribution is performed by using ANSYS (CFX Tool) software. The paper finds the volumetric efficiency of the engine at different angles of the throttle plate and indicates the effects of the current atmospheric condition using ethanol-blended gasoline. The contribution of this paper lies in achieving a better fuel (gasoline & ethanol) economy by modelling the carburettor design by using split throttle plate. Keywords: Carburettor, CFX tool, Ethanol, Throttle plate, Solid works, Venture Introduction SI engines use volatile liquid fuels, here Air-Fuel mixture is prepared outside the engine cylinder 15 . The process of forming a combustible air-fuel mixture is called carburetion and the mechanical device which performs this action is called as Carburettor 1,2 . The carburettor constitutes a complex set of passage 7 , i.e. venturi section, throttle plate, choke valve, fuel metering jet etc. and the compressible flow varies from laminar to fully turbulent due to rapid changes in operating conditions as well as changes in pressure drop at the throat and atmospheric temperature. The 3D scanner is used to capture the object shape in digital form and manufactured prototype with the support of AM system 8, 11, 12 . 3D scanners capture accurately part image in a three-dimensional format and produce point cloud data from which extracts surface details in few seconds. The digital data so generated is compatible with available designing, testing and inspection software 13,14 . Spark ignition (SI) engine fuels Spark ignition (SI) engines use gasoline which is highly volatile and hydrocarbons emissions from SI engines like CO2, NOx, CO, etc. are emitted as particulate matter 19 . According to UNFCCC India has to limit its carbon footprint; thus an alternative fuel like ethanol is blended in various proportions with the gasoline 9 . Ethanol is a bio-based renewable resource and is oxygenated, which reduces the particulate emission from SI engine. Ethanol has a composition of 95 percent alcohol and five percent water, but it has a nature of absorbing moisture from the atmosphere. The most available ethanol contains 5% to 20% of water which is known as aqueous ethanol 3 . The chemical properties of the ethanol used in the experimentation are given below;  Boiling point of ethanol 15 –78.15ᵒC  Specific gravity of ethanol 15 – 0.79  Specific gravity of gasoline 15 – 0.75  Viscosity 15 – 0.15*10^ (-6) m^2/s at 20ᵒC —————— * Author for Correspondence E-mail: ahaleem@jmi.ac.in