TECHNOLOGY ENGINES THREE-CYLINDER DIESEL ENGINE IN HYUNDAI GRAND i10 Hyundai Motor Company (HMC) decided to develop the Grand i10, a higher-end version of i10, to cater to the Indian high-end compact car market. Powering the vehicle is the U2 1.1 l three-cylinder diesel engine, which offers significant fuel economy and enjoyable driving experience. It has been mass-produced and sold since 2011, and the performance and fuel efficiency has already been proven in the European market. AUTHORS LEE BYUNG CHUL is Part Manager in the Passenger Car Diesel Engine Engineering Design department at Hyundai Motor Com- pany in Namyang (South Korea). PYO SOON CHAN is Part Manager in the Passenger Car Diesel Engine Test department at Hyundai Motor Company in Namyang (South Korea). INTRODUCTION adapted to terrain and driving condi- tions of India. The U2 1.1 l three-cylinder diesel engine Produced at Hyundai’s engine plant in achieves a class-leading CO2 emission of Chennai, Tamil Nadu, the U2 1.1 l three- CHO SUNG MOON is Part Manager in the Passenger Car 85 g/km. In the development of this cylinder diesel engine delivers a maxi- Diesel Engine Test department at engine, engineers at Hyundai focussed on mum power of 68 hp at 4,000 rpm, better Hyundai Motor Company in Namyang four key areas: than many of its competitors in the mar- (South Korea). :: Better fuel economy, which is offered ket. Torque peaks at about 160 Nm in an by competing models in the same rpm range of 1,500 to 2,750. Injection class; pressure of 1,800 bar and a low compres- :: Power and performance that satisfy the sion ratio of 16:0 optimise combustion user both on urban roads and the stability and cold start performance, 1. highway; :: Competitiveness in terms of mainte- EBRAHIM SHAKIL is Deputy Manager in the Body Mov- nance cost realised through localisa- ENGINE HARDWARE ing Engineering Design at Hyundai tion of major components, and the Motor India Engineering in Hyderabad local production of the engine; and A number of hardware solutions have (India). :: Performance, durability and robustness been applied in the engine to comply with 44 www.autotechreview.com Item Unit U2 1.1 l engine for Grand i10 mised the specifications and tolerances Engine configuration - In-line three-cylinder of important moving parts to reduce fric- Valve train - DOHC 4-valve tion. The tension of the piston rings, in particular, has been optimised allowing Displacement cc 1,120 for maximum combustion pressure and Bore × stroke mm 75 × 84.5 oil consumption. Max. power hp/rpm 68/ 4,000 The timing system of the U2 engine Max. torque Nm/rpm 160/ 1,500 - 2,750 uses a no-maintenance chain system Compression ratio - 16:0 (driven by cams and a high-pressure pump), while the layout of the chain Turbocharger - WGT (Wastegate Turbocharger) has been optimised using a finite ele- Fuel system - Delphi ment method and a multi-body simula- Fuel injection pressure bar 1,800 tion technique. Emission standards - BS IV (Bharat Stage IV) 1 General specifications of the U2 1.1 l three-cylinder diesel engine DESIGN FEATURES BS IV emission norms, and achieve higher ensures sufficient stiffness, resulting in Some important design features were power and NVH performance than those better NVH performance. The use of a implemented to achieve enough potential offered by competitors. The combination gear driven balance shaft, in particular, for minimising CO2 emissions, achieving of a 1,800 bar common rail system and an completely eliminated the levels of pri- BS IV compliance, maximising power out- optimised waste gate turbocharger has mary unbalance, which is inherent to put and reaching a comfortable acoustic ensured sufficient engine power. A water- other three-cylinder designs. A lightweight behaviour. These include the exhaust cooled exhaust gas recirculation (EGR) cylinder block that optimises the structure manifold integrated turbocharger, com- system controlled by electronic solenoid and spoke thickness has been used to mon rail system, balance shaft module, valves lowers the levels of nitrogen oxides reduce engine weight. bed plate type lower crankcase and thin (NOx) in order to satisfy the BS IV regula- The turbocharger turbine housing, on wall cylinder block, 2. tions, while a separate cooling circuit is the other hand, is integrated with the configured for the valve housing to ensure exhaust manifold. This integrated struc- the stable operation of valves in high-tem- ture minimises exhaust power loss, not LOCALISED COMPONENT perature exhaust gases. only enhancing performance and fuel DEVELOPMENT The bedplate structure, tested in previ- efficiency, but also reducing weight and ous four-cylinder ‘U’ engine models, cost. Engineers at Hyundai also opti- Hyundai undertook a major localisation common Rail System Exhaust Manifold Integrated Turbocharger Bed Plate Type Lower Crankcase Thin Balance Shaft Module Wall Cylinder Block 2 Localised development of components used in the U2 1.1 l diesel engine autotechreview February 2014 Volume 3 | Issue 2 45 TECHNOLOGY ENGINES of sub-components that contributed to the enhancement of fuel efficiency and performance. For the demand of further weight EGR Valve reduction, it was also decided to change the material for the vanes from steel to plastic. Vanes play an important role in generating vacuum. The decision to move to plastics resulted in weight reduction and improved precision – fac- tors that affect driveline torque, allowing for the enhancement of pump perfor- mance and fuel efficiency. Most of all, the primary focus of local- ised component development was to ensure a level of quality that surpasses that of any other mass-produced engines. The achievement of this quality goal was EGR Cooler due to the well-organised collaboration 3 Water-Cooled EGR system among local suppliers, the development and quality control departments of Hyun- initiative with the new U2 1.1 l diesel pressure control for proportional pressure dai Motors India and its research organi- engine, leading to the localisation of 50 control. The constant pressure control sys- sation. A great number of HMC research- different components. This was done not tem uses the pressure from the compres- ers, in particular, were set apart since the just to ensure the technological compe- sor to control the actuator and offers cost early stage of the development to directly tence of local suppliers in India, but to and weight advantages by eliminating the support and cooperate with suppliers. ensure efficient supply of parts and reduc- need for solenoid valves and other com- tion of parts so as to minimise customer’s ponents, required for proportional pres- maintenance cost. sure control. Its compact structure also FUEL INJECTION SYSTEM The localised development efforts have provides better durability. enlisted a broad array of prominent auto- The vacuum pump, playing an The U2 1.1 l engine uses a Delphi com- motive parts manufacturers. important role in generating brake mon rail fuel injection system, offering Hinduja (India) replaced Daedong Met- booster pressure, has been locally devel- the maximum injection pressure of 1,800 als (Korea) in the development of the oped by UCAL of material for the cylinder block, the main India replacing 180 60 structural component of the engine. Hon- Kamtec of Korea. It eywell of India replaced Keyyang Preci- was not only the sion of Korea in the development of the replacement of the turbocharger, the key component deter- supplier, but also the 160 50 mining the performance of the engine. optimisation of the Honeywell also substituted the constant material and structure 140 40 ) rque (Nm) Power (kw To 120 30 Turbocharger 100 20 DOC 80 10 1000 2000 3000 4000 Rotational frequency (rpm) 4 The after treatment system used in the U2 engine 5 Full load power and torque 46 www.autotechreview.com TECHNOLOGY ENGINES bar. The high injection pressure of 1,800 AFTER TREATMENT SYSTEM reducing NVH. A structural analysis was bar has resulted in the reduction of the performed to determine the effects of the durations of fuel injection, boosting per- The exhaust purifier employs DOC (die- shape and location of the ribs on noise formance. A total of eight injector nozzle sel oxidation catalyst) to meet the BS IV characteristics, allowing engineers to find holes have been used to minimise hole emission regulations. The exhaust puri- the optimal shape of the oil sump. cross sections. The optimised injector fier is installed right after the turbo- The bell housing shape in the match- nozzle hole design has further atomised charger, as shown in 4, reducing cata- ing parts between the engine and trans- injected fuel and improved air mixing, lyst light-off time and catalyst size as mission has been determined by measur- contributing to stable performance and well as minimising carbon monoxide ing the levels of sound pressure in the the reduction of toxicants in exhaust and hydrocarbon emissions. passenger compartment, which, com- gases. Despite the minimised cross sec- bined with the use of the bedplate and tions of nozzle holes, the optimised length the noise characteristics of the previously of the holes has also added robustness ENGINE PERFORMANCE mentioned chain system, the oil sump against choking. and other components has resulted in These changes have made possible Yet another development focus was the excellent NVH performance. precision control even with smaller balance between the low-speed torque injections of fuel as well as shorter and maximum power, which determines intervals with multi-point injection. The the drivability of cars. As such, efforts VEHICLE PERFORMANCE AND FUEL optimisation of engine control variables have been made to ensure the maximum EFFICIENCY coupled with the optimal combination torque of 160 Nm over a broad range from of single and double pilot injection has 1,500 to 2,750 rpm, 5.