Browse Publications Technical Papers 2001-01-3682
2001-09-24

Effect of Reduced Boost Air Temperature on Knock Limited Brake Mean Effective Pressure (BMEP) 2001-01-3682

The effect of low temperature intake air on the knock limited brake mean effective pressure (BMEP) in a spark ignited natural gas engine is described in this paper. This work was conducted to demonstrate the feasibility of using the vaporization of liquefied natural gas (LNG) to reduce the intake air temperature of engines operating on LNG fuel. The effect on steady-state emissions and transient response are also reported. Three different intake air temperatures were tested and evaluated as to their impact upon engine performance and gaseous emissions output. The results of these tests are as follows. The reduced intake air temperature allowed for a 30.7% (501 kPa) increase in the knock-limited BMEP (comparing the 10°C (50°F) intake air results with the 54.4°C (130°F) results). Exhaust emissions were recorded at constant BMEP for varying intake air temperatures. The raw BSNOx emissions were reduced by 0.6% (0.1 g/kW-hr, not a significant change) due to the chilled air, but the corrected BSNOx emissions were reduced by 17.8% (3.4 g/kW-hr). The BSHC emissions were reduced by 39.9% (0.5 g/kW-hr). The BSCO emissions, however, were increased by 7.5% (0.2 g/kW-hr). Transient engine response revealed that the use of reduced temperature intake air provided a 15.3% (1.43 second) improvement in the time required to obtain an engine speed of 1600 rpm. Similarly, the chilled intake air reduced the time required to reach a set manifold air pressure of 212.4 kPa (30.8 psia) by 11.5% (1.21 seconds).

SAE MOBILUS

Subscribers can view annotate, and download all of SAE's content. Learn More »

Access SAE MOBILUS »

Members save up to 18% off list price.
Login to see discount.
Special Offer: Download multiple Technical Papers each year? TechSelect is a cost-effective subscription option to select and download 12-100 full-text Technical Papers per year. Find more information here.
We also recommend:
TECHNICAL PAPER

Air -Fuel Ratio Calculation for a Natural Gas Fuelled Spark Ignition Engine

2004-01-0640

View Details

TECHNICAL PAPER

Particle Emission Measurements in a SI CNG Engine Using Oils with Controlled Ash Content

2019-01-0053

View Details

TECHNICAL PAPER

Instantaneous In-Cylinder Hydrocarbon Concentration Measurement during the Post-Flame Period in an SI Engine

1999-01-3577

View Details

X