Thermal Management Opportunity on Lubricant Oil to Reduce Fuel Consumption and Emissions of a Light-Duty Diesel Engine

Abstract

The high viscosity of the lubricant oil in internal combustion engines at cold starts is responsible for poor friction reduction and inadequate thermal stabilization of metallic masses and represents a major bottleneck in the efforts to reduce specific fuel consumption and pollutant emissions. Consequently, the possibility of integrating techniques for proper thermal management of the lubricant oil on internal combustion engines is of utmost importance to both homologation and daily on-road operation. Main options for reducing the warm-up time for the engine lubricant are the upgrade of the engine cooling and lubricating circuits, dedicated heating, different flow management of the oil/coolant heat exchanger, a renewed design of the oil sump or a thermal storage section to increase the oil temperature in the early phases of the warm up. The paper presents a new opportunity, using a hot storage medium to heat up the oil in the early phase of a driving cycle. A certain quantity of hot water, so, is stored in a tank, which can be used to warm up the lubricating oil when the engine is started up. The heating of this service water can be done by using exhaust gas heat, which is always wasted in the atmosphere. The activity is realized on an IVECO 3.0 L light-duty diesel engine, during a transient cycle (NEDC) on a dynamometric test bench. The benefits in terms of both fuel consumption and CO2 emissions reduction. The characterization of the backpressure associated with an eventual additional heat exchangers and the more complex layout of the oil circuit is assessed, as well as the transient effects produced by the faster oil warm-up and oil-coolant interaction on the engine thermal stabilization.

Emission Reduction from a Light-Duty Diesel Vehicle over Two Driving Cycles through Dynamic Correction Calibration

“…Di Battista et al 15 studied that shortening the rising time of the oil temperature could reduce fuel consumption in the new European driving cycle (NEDC) by 1.7%. Therefore, to eliminate the influence of the oil on the test results, the same types of oil and oil filter were replaced before the test.…”

Comparative Analysis of Soft Computing Models for Predicting Viscosity in Diesel Engine Lubricants: An Alternative Approach to Condition Monitoring

“…Lubricants play a critical role in diesel engines, contributing to the reduction of friction, heat management, improvement of fuel efficiency, and reduction of emissions. − Friction reduction among the moving components of an engine, crucial for preventing wear and tear that could compromise performance and potentially lead to engine failure, is facilitated by lubricants. , The utilization of poor-quality lubricant in diesel engines can result in various adverse consequences, including increased wear, reduced component longevity, decreased fuel efficiency, and heightened emissions . Several adverse effects on diesel engine lubrication are influenced by the lubricant viscosity.…”

Model Parameterized Assessment of a Thermal Storage Unit for Engine Oil Warm-up Improvement

“…Widely considered for a thermoelectric generation [26,27], on board thermal storage usually involves phase change materials as the storage medium [28,29] or innovative layouts featuring nanostructured materials [30]. Way less attention has been tributed to its potential for direct feeding of thermal energy to the lubricant, even if preliminary numerical analysis [31] and experimental activities [32] invite to investigate that possibility. Furthermore, on board thermal storage provides the additional appealing advantage of decoupling the warm-up of the oil from the engine one, since the thermal energy would be readily available for transfer.…”

“…Therefore, the figure for fuel consumption and related CO2 emissions reduction expected can be evaluated in an experimental way. According to previous experimental works [23,25,32], it is expected about 2-3%, but a specific experimental setup and testing activity will be done in next future.…”