Investigation of emission characteristics affected by new cooling system in a diesel engine

Abstract

In a typical cooling system of automotive engine, a mechanical water pump is used to control the flow rate of coolant. However, this traditional cooling system is not suitable for a high efficiency performance in terms of fuel economy and exhaust emission. Therefore, it is necessary to develop a new technology for engine cooling systems. These days, the electronic water pump is spotlighted as the new cooling system of an engine. The new cooling system can provide more flexible control of the coolant flow rate and the engine temperature, which used to be strongly relied on the engine driving conditions such as load and speed. In this study, an engine experiment was carried out on a New European Drive Cycle (NEDC) with a 2.7L diesel engine. The electric water pump operated by BLDC motor and the electronic valve were installed in the cooling system to control the coolant flow rate and temperature. This paper explains that the exhaust emissions were reduced with an increase in the engine temperature and a decrease in the coolant flow. From this experiment, we found that increasing coolant temperature had a significant effect on reducing the emissions (e.g. THC and CO). Decreasing coolant flow also affected the reduction of emissions. In contrast, NOx emission was observed to increase in these conditions.

Analysis of IC Engine Performance Using Nano Fluid as Coolant in Radiator – A Review

“…[4] Nano flu ids were first invented by Heat transfer coefficient of different nano fluid is higher than that of the base liquid and increase with increasing the Reynolds number and particle concentrations. For the pressure drop, it is also shown that the pressure drop of nano fluids was slightly higher than the base fluid and increases with increasing the volume Concentrations.…”

Development and Validation of a Submodel for Thermal Exchanges in the Hydraulic Circuits of a Global Engine Model

“…Improvements of the thermal performance of cooling and lubricating systems promise to deliver a reduction of emissions. Diverse authors have reported reductions of unburned hydrocarbons (HC) [5], nitrogen oxides [6] and carbon monoxide (CO) [7] after optimizing the cooling system. Moreover, emissions of carbon dioxide (CO2) and fuel consumption can be cut through improved cooling and lubrication strategies: optimized cooling by controlling the coolant flow [8], lower friction losses by controlling the lubricant temperature [9] or reduced ancillary losses through electrification [10].…”

Improvement of the air-cooled system on an engine cylinder head and its analysis

“…[3][4][5] For the cooling of the water-cooled engine, the difficulty lies in the efficient allocation of the coolant flow between different regions. In general, water diversion holes and various flow-guided structures are adopted to distribute the coolant flow.…”

“…Heat load is an important factor affecting the reliability and durability of the engine; too high temperature of the engine cylinder head will lead to heating crack, ablation, creep deformation of the cylinder head, a sharp decline in the hardness and strength of the materials and the destruction, coking, and other problems of lubrication oil film, 1,2 and it will also increase fuel consumption, and CO and HC emissions. [3][4][5] For the cooling of the water-cooled engine, the difficulty lies in the efficient allocation of the coolant flow between different regions. In general, water diversion holes and various flow-guided structures are adopted to distribute the coolant flow.…”