Alberto Boretti

A new method to warm up lubricating oil to improve the fuel efficiency during cold start

Cold start driving cycles exhibit an increase in friction losses due to the low temperatures of metal and media compared to normal operating engine conditions. These friction losses are responsible for up to 10% penalty in fuel economy over the official drive cycles like the New European Drive Cycle (NEDC), where the temperature of the oil even at the end of the 1180 s of the drive cycle is below the fully warmed up values of between 100°C and 120°C. At engine oil temperatures below 100°C the water from the blow by condensates and dilutes the engine oil in the oil pan which negatively affects engine wear. Therefore engine oil temperatures above 100°C are desirable to minimize engine wear through blow by condensate. The paper presents a new technique to warm up the engine oil that significantly reduces the friction losses and therefore also reduces the fuel economy penalty during a 22°C cold start NEDC. Chassis dynamometer experiments demonstrated fuel economy improvements of over 7% as well as significant emission reductions by rapidly increasing the oil temperature. Oil temperatures were increased by up to 60°C during certain parts of the NEDC. It is shown how a very simple sensitivity analysis can be used to assess the relative size or efficiency of different heat transfer passes and the resulting fuel economy improvement potential of different heat recovery systems system. Due to its simplicity the method is very fast to use and therefore also very cost effective. The method demonstrated a very good correlation for the fuel consumption within ±1% compared to measurements on a vehicle chassis roll.

Improvements of Vehicle Fuel Economy Using Mechanical Regenerative Braking

The paper presents a mixed theoretical and experimental evaluation of the improvements in fuel economy that follow the introduction of a mechanical Kinetic Energy Recovery System (KERS) on a full size passenger car. This system, made up of a high speed storage flywheel and a Constant Variable Transmission (CVT), has a full regenerative cycle overall efficiency about twice the efficiency of battery-based hybrids. With reference to the baseline configuration having a 4L gasoline engine, adoption of a KERS may reduce the fuel consumption covering the NEDC by 25% without downsizing, and by 33% downsizing the engine to 3.3L.

The Inconvenient Truth: Ocean Level Not Rising in Australia

There is a claim that, by the end of this century, Australian coastal communities will experience rising sea levels of up to more than 1 metre because of the anthropogenic carbon dioxide emissions causing global warming. This is the major argument supporting the Australias Carbon Tax set to become law early next year. Under this legislation, 500 large Industrial manufacturers who emit carbon dioxide will be compelled to pay, from profitable income, for every tonne of carbon dioxide. Most of these emitters are electrical power generation and mining companies and heavy industry manufacturers. To compensate households for projected rising costs, due to the increased taxing pricing caused by this Carbon Tax, the government will cut income tax for smaller industries, boost payments to pensioners and offer various lump sum payments to small companies. This Australian scheme covers approximately 60% of Australias emissions, making it the most broad-based scheme presented to the world. This carbon pricing will affectively apply to the 22.6 million Australians (2011) living in a 7,682,300 square kilometres country which is a relatively small number, proportional to the 7 billion people worldwide. The paper shows that locally and globally measured data, collected over short and long time scales, prove that the claim of sea level sharply accelerating is false.

Exploring the Advantages of Atkinson Effects in Variable Compression Ratio Turbo GDI Engines

The Atkinson cycle engine is basically an engine permitting the strokes to be different lengths for improved light loads fuel economies. Variable compression ratio is the technology to adjust internal combustion engine cylinder compression ratio to increase fuel efficiency while under varying loads. The paper presents a new design of a variable compression ratio engine that also permits an expansion ratio that may differ from the compression ratio therefore generating an Atkinson cycle effect. The stroke ratio and the ratio of maximum to minimum in-cylinder volumes may change with load and speed to provide the best fuel conversion efficiency. The variable ratio of maximum to minimum in-cylinder volumes also improves the full load power output of the engine. Results of performance simulations are proposed for a gasoline engine 2 Litres, in-line four, turbocharged and direct injection showings significant fuel savings during light and medium loads operation as well as improvement of full load output and fuel efficiency.

The lean burn direct-injection jet-ignition flexi gas fuel LPG/CNG engine

This paper explores through engine simulations the use of LPG and CNG gas fuels in a 1.5 liter Spark Ignition (SI) four cylinder gasoline engine with double over head camshafts, four valves per cylinder equipped with a novel mixture preparation and ignition system comprising centrally located Direct Injection (DI) injector and Jet Ignition (JI) nozzles. With DI technology, the fuel may be introduced within the cylinder after completion of the valve events. DI of fuel reduces the embedded air displacement effects of gaseous fuels and lowers the charge temperature. DI also allows lean stratified bulk combustion with enhanced rate of combustion and reduced heat transfer to the cylinder walls creating a bulk lean stratified mixture. Bulk combustion is started by a Jet Ignition (JI) system introducing in the main chamber multiple jets of reacting gases for enhanced rate of combustion, initiating main chamber burning in multiple regions with reduced sensitivity to mixture state and composition. Coupling of JI and DI allows the development of a lean burn engine making possible operation up to main chamber overall fuel-to-air equivalence ratios reducing almost to zero and throttle-less load control by quantity of fuel injected as in the diesel engine. Results are presented in terms of maps of brake specific fuel consumption (BSFC) and efficiency and maximum power densities. Load variations are obtained by varying the air to fuel equivalence ratio from ?=1 up to ?=6.6. Maximum power densities running ?=1 are 80 hp/liter (60 kW/liter) with CNG and almost 90 hp/liter (67 kW/liter) with LPG. BSFCs are as low as 200 and 190 g/kWh and brake efficiencies are up to 39 and 37% respectively with LPG and CNG running lean ?=1.65. Low BSFCs and high brake efficiencies are possible from 25 to 100% of engine load.

CNG Fueling Strategies for Commercial Vehicles Engines-A Literature Review

The paper presents a survey of the opportunities to convert compression ignition heavy duty truck engines to work on single or dual fuel modes with CNG. In one popular option, the compression ignition engine is converted to spark ignition with throttle load control and port injection of the CNG. In another option of increasing popularity, the LNG is directly injected and ignited by direct injection of pilot Diesel. This latter option with direct injection of natural gas and diesel through separate injectors that are fully independent in their operation is determined to be the most promising, as it is expected to deliver better power density and similar part load fuel economy to Diesel.

Novel Crankshaft Mechanism and Regenerative Braking System to Improve the Fuel Economy of Passenger Cars

Improvements of vehicle fuel economy may be achieved by the introduction of advanced internal combustion engines (ICE) improving the fuel conversion efficiency of the engine and of advanced power trains (PWT) reducing the amount of fuel energy needed to power the vehicle. The paper presents a novel design of a variable compression ratio advanced spark ignition engine that also permits an expansion ratio that may differ from the compression ratio hence generating an Atkinson cycle effect. The stroke ratio and the ratio of maximum to minimum in-cylinder volumes may change with load and speed to provide the best fuel conversion efficiency. The variable ratio of maximum to minimum in-cylinder volumes also improves the full load torque output of the engine. The paper also presents an evolved mechanical kinetic energy recovery system delivering better round trip efficiencies with a design tailored to store a smaller quantity of energy over a reduced time frame with a non-driveline configuration. Simulations show an improvement of full load torque output and fuel conversion efficiency. Brake specific fuel consumption maps are computed for a gasoline engine 2 litres, in-line four, turbocharged and directly fuel injected showings significant fuel savings during light and medium loads operation. Results of vehicle driving cycle simulations are presented for a full size car equipped with the 2 L turbo GDI engine and a compact car with a downsized 1 L turbo GDI engine. These results show dramatic improvements of fuel economies for similar to Diesel fuel energy usage and CO2 production. The turbo GDI engines with the alternative crank trains offer better than hybrids fuel economies if the vehicles are also equipped with the novel mechanical kinetic energy recovery system (KERS) recovering the braking energy to reduce the thermal energy supply in the following acceleration of a driving cycle.

100% LPG Long Haul Truck Conversion - Economy and Environmental Benefits

Advanced Vehicle Technologies (AVT), a Ballarat Australia based company, has developed the Worlds first diesel to 100% LPG conversion for heavy haul trucks. There is no diesel required or utilized on the trucks. The engine is converted with minimal changes into a spark ignition engine with equivalent power and torque of the diesel. The patented technology is now deployed in 2 Mercedes Actros trucks. The power output in engine dynamometer testing exceeds that of the diesel (in excess of 370 kW power and 2700 Nm torque). In on-road application the power curve is matched to the diesel specifications to avoid potential downstream power-train stress. Testing at the Department of Transport Energy & Infrastructure, Regency Park, SA have shown the Euro 3 truck converted to LPG is between Euro 4 and Euro 5 NOx levels, CO2 levels 10% better than diesel on DT80 test and about even with diesel on CUEDC tests. The average fuel ratio of LPG tests versus diesel tests over 7 points from 80 kW to 180 kW is 1.67:1. The conversion is already operational in fleets. The conversion to LPG permits a better economy, a better environment and a better energy security. The truck conversion permits lower operating cost and significantly reduced fuel cost. The LPG has a lower fuel cost per unit energy. The savings are almost

Design of Rankine Cycle Systems to Deliver Fuel Economy Benefits over Cold Start Driving Cycles

300 per 1000 km. These fuel costs are based on an average wholesale price including rebates over the past 6 months of

Exploring the Advantages of Variable Compression Ratio in Internal Combustion Engines by Using Engine Performance Simulations

0.51/L LPG and