Combustion Characteristics of Spray Flames of Diesel and Palm Methyl Ester at Lean Inlet Conditions

Phase Reaction ◽

Fuel Flow ◽

Spray Flames ◽

Reaction Zones ◽

Inlet Conditions ◽

Basic Studies ◽

Emission Index ◽

Palm Methyl Ester (PME) is an attractive alternate fuel to petroleum diesel because it can be produced from a renewable source, is close to being carbon-neutral in the environment, and has many properties similar to those of petroleum fuels. Although a few engine studies have been completed using PME, basic studies on the combustion of PME sprays are limited. Hence, the objective of this investigation was to study the combustion characteristics of spray flames of PME and diesel at three equivalence ratios: 0.4, 0.6 and 0.8. The liquid fuel was atomized and combusted with air in a heated environment; the coflow air temperature was maintained at 65% of the midpoint of the boiling point range of the fuels. The equivalence ratio was changed by altering the fuel flow rate, while maintaining the atomizing and coflow air flow rates constant, thus maintaining the gas velocity field invariant. The PME flames were shorter and less luminous than the diesel flames and had significant near-burner homogeneous-gas-phase reaction zones. The global CO emission index of the PME flames was higher than that of diesel flames at equivalence ratios of 0.4 and 0.6. The NO emission index of the PME flames was almost twice that of the diesel flames. The in-flame concentration profiles highlighted the effects of the significant fuel-bound oxygen content in PME.

Combustion Characteristics of Partially Premixed Prevaporized Palm Methyl Ester and Jet A Fuel Blends

Journal of Energy Resources Technology ◽

10.1115/1.4031966 ◽

2015 ◽

Vol 138 (1) ◽

Cited By ~ 9

Author(s):

A. Balakrishnan ◽

R. N. Parthasarathy ◽

S. R. Gollahalli

Keyword(s):

Methyl Ester ◽

Equivalence Ratio ◽

Volume Concentration ◽

Laminar Flame ◽

Phase Reaction ◽

No Emission ◽

Combustion Properties ◽

Emission Index ◽

Palm methyl ester (PME) is an attractive alternate biofuel produced by the transesterification of palm oil with methanol. This paper is a sequel to our earlier papers on the comparison of the flame structure and emission characteristics of neat PME with those of petroleum-derived fuels (No. 2 diesel and neat Jet A). Blends of prevaporized Jet A fuel and PME (25%, 50%, and 75% by volume) were studied in a laminar flame environment at burner-exit equivalence ratios of 2, 3, and 7. The global combustion characteristics including flame length, CO and NO emission indices, radiative heat fraction, and in-flame profiles of species concentration (CO, CO2, NO, and O2), temperature, and soot volume concentration were measured. The global CO emission index decreased significantly with the PME content in the blend at an equivalence ratio of 7; a 30% reduction was observed with the addition of 25% PME by volume, and a further reduction of 25% was observed with the addition of another 25% PME. The global NO emission index of the neat PME flame was 35% lower than that of the Jet A flame at an equivalence ratio of 2. The near-burner homogeneous gas-phase reaction zone increased in length with the addition of PME at all equivalence ratios. The concentration measurements highlighted the nonmonotonic variation of properties with the volume concentration of PME in the fuel blend. The fuel-bound oxygen and hydrogen of PME affected the combustion properties significantly.

Laminar Flame Characteristics of Partially Premixed Palm Methyl Ester Gas Flames

Volume 6A: Energy ◽

10.1115/imece2013-63005 ◽

2013 ◽

Cited By ~ 3

Author(s):

Diego Romero ◽

Ramkumar N. Parthasarathy ◽

Subramanyam R. Gollahalli

Keyword(s):

Methyl Ester ◽

Flow Rate ◽

Equivalence Ratio ◽

Volume Fraction ◽

Laminar Flame ◽

Soot Volume Fraction ◽

Fuel Flow ◽

Combustion Properties ◽

Emission Index ◽

Palm methyl ester (PME) is a renewable biofuel that is produced by the transesterification of palm oil; it is a popular alternative fuel used in the transportation sector. The objective of this investigation was to study the combustion characteristics of flames of pre-vaporized diesel and PME in a laminar flame environment at initial equivalence ratios of 2, 3 and 7 and to isolate the factors attributable to chemical structure of the fuel. The equivalence ratio was changed by altering the fuel flow rate, while maintaining the air flow rate constant. The global CO emission index of the PME flames was significantly lower than that of the diesel flames; however, the global NO emission index was comparable. The radiative fraction of heat release and the soot volume fraction were lower for the PME flames compared to the diesel flames. The peak temperatures were comparable at an equivalence ratio of 2, but at higher equivalence ratios, the peak temperatures in the PME flames were higher. The measurements highlight the differences in the combustion properties of biofuels and petroleum fuels and the coupling effects of equivalence ratio.

Combustion Characteristics of Spray Flames of Canola Methyl Ester/Diesel Blends in a Furnace

Volume 6A: Energy ◽

10.1115/imece2013-63004 ◽

2013 ◽

Author(s):

Cory D. Morton ◽

Victor H. Tran ◽

Ramkumar N. Parthasarathy ◽

Subramanyam R. Gollahalli

Keyword(s):

Methyl Ester ◽

Heat Release ◽

Volume Fraction ◽

Flame Temperature ◽

Soot Volume Fraction ◽

Spray Flame ◽

Spray Flames ◽

Refractory Bricks ◽

Emission Index

The combustion characteristics of spray flames of canola methyl ester (CME) and blends with diesel fuel within a re-radiating environment were studied. The combustion chamber was lined with refractory bricks that were preheated to about 725 K (1305 °R). The flow rates of the fuels provided a constant heat release rate of about 7.33 kW (25,000 BTU/hr) at atmospheric pressure. Measurements of flame temperature, in-flame concentrations, global emissions, flame radiation and soot volume fraction were taken. The global CO emission index was significantly lower in the biofuel blend spray flames compared to that of the diesel spray flame. The global NO emission index was comparable for all spray flames, which agreed with peak flame temperature and in-flame NO concentration measurements. The radiative fraction of heat release was also comparable for all spray flames.

Laminar Flame Characteristics of Partially Premixed Prevaporized Palm Methyl Ester and Diesel Flames

Journal of Energy Resources Technology ◽

10.1115/1.4027406 ◽

2014 ◽

Vol 136 (3) ◽

Cited By ~ 11

Author(s):

D. Romero ◽

R. N. Parthasarathy ◽

S. R. Gollahalli

Keyword(s):

Methyl Ester ◽

Flow Rate ◽

Equivalence Ratio ◽

Volume Fraction ◽

Laminar Flame ◽

Soot Volume Fraction ◽

Fuel Flow ◽

Combustion Properties ◽

Emission Index ◽

Palm methyl ester (PME) is a renewable biofuel that is produced by the transesterification of palm oil and is a popular alternative fuel used in the transportation sector, particularly in Asia. The objective of this investigation was to study the combustion characteristics of flames of prevaporized number 2 diesel and PME in a laminar flame environment at initial equivalence ratios of 2, 3, and 7 and to isolate the factors attributable to chemical structure of the fuel. The equivalence ratio was changed by altering the fuel flow rate, while maintaining the air flow rate constant. The global CO emission index of the PME flames was significantly lower than that of the diesel flames; however, the global NO emission index was comparable. The radiative fraction of heat release and the soot volume fraction were lower for the PME flames compared to those in the diesel flames. The peak temperatures were comparable in both flames at an equivalence ratio of 2, but at higher equivalence ratios, the peak temperatures in the PME flames were higher. The measurements highlight the differences in the combustion properties of biofuels and petroleum fuels and the coupling effects of equivalence ratio.

Volume 4: Energy Systems Analysis, Thermodynamics and Sustainability; Combustion Science and Engineering; Nanoengineering for Energy, Parts A and B ◽

Combustion Properties of Spray Flames of Canola Methyl Ester and Diesel Blends

10.1115/imece2011-63597 ◽

2011 ◽

Author(s):

Cristian Aldana ◽

Ramkumar N. Parthasarathy ◽

Subramanyam R. Gollahalli

Keyword(s):

Methyl Ester ◽

Flame Temperature ◽

Combustion Products ◽

Phase Reaction ◽

Fuel Blend ◽

Fuel Blends ◽

No Formation ◽

Spray Flames ◽

Combustion Properties ◽

No Emissions

Canola methyl ester (CME) is a biofuel that is produced by the transesterification of canola oil; it is renewable, carbon-neutral and low in sulfur content. The objective of this study was to document the combustion characteristics of spray flames of CME and No 2 diesel (petroleum fuel) blends. Three blends with 25%, 50% and 75% volume concentration of CME were studied. The fuel was atomized and mixed with air in a heated environment at a supply equivalence ratio of 0.62. Measurements of global CO and NO emissions, inflame temperature and in-flame concentrations of combustion products were made. The near-injector homogeneous gas-phase reaction zone increased in size with the addition of CME. The global CO and NO emissions decreased with the increase in CME content in the fuel blend. The in-flame NO concentration profiles and flame temperature profiles followed similar trends, suggesting that the thermal mechanism of NO formation was dominant in these flames.

49th AIAA Aerospace Sciences Meeting including the New Horizons Forum and Aerospace Exposition ◽

Combustion Characteristics of Spray Flames of Soy Methyl Ester and Diesel Blends

10.2514/6.2011-618 ◽

2011 ◽

Author(s):

Cristian Aldana ◽

Subramanyam Gollahalli ◽

Ramkumar Parthasarathy

Keyword(s):

Methyl Ester ◽

Spray Flames ◽

Soy Methyl Ester

Laminar Partially Premixed Flames of Blends of Pre-Vaporized Jet-A Fuel and Palm Methyl Ester

Volume 6A: Energy ◽

10.1115/imece2014-36930 ◽

2014 ◽

Cited By ~ 1

Author(s):

Arun Balakrishnan ◽

Ramkumar N. Parthasarathy ◽

Subramanyam R. Gollahalli

Keyword(s):

Methyl Ester ◽

Flow Rate ◽

Volume Fraction ◽

Air Flow ◽

Soot Volume Fraction ◽

Flame Length ◽

Phase Reaction ◽

Combustion Properties ◽

Partially Premixed ◽

Biofuels, such as palm methyl ester (PME), are attractive alternates to petroleum fuels. In order to isolate the effects of fuel chemistry on the combustion properties, laminar partially premixed pre-vaporized flames of blends of Jet-A and PME (volume concentrations of 25%, 50%, 75% PME) were studied. A stainless steel circular tube (ID of 9.5 mm) served as the burner. The liquid fuel was supplied with a syringe pump into a high temperature (390°C) air flow to vaporize it completely without coking. The fuel flow rate was maintained constant and the air flow rate adjusted to obtain burner-exit equivalence ratios of 2, 3 and 7. The global flame properties including flame length, CO and NO emission indices, radiative heat fraction and in-flame properties including gas concentration (CO, CO2, NO, O2), temperature and soot volume fraction were measured. The near-burner homogeneous gas-phase reaction zone increased in length with the addition of PME at all equivalence ratios. The concentration and global emission measurements highlight the non-monotonic variation of properties with the volume concentration of PME in the fuel. The fuel-bound oxygen of PME affected the combustion properties significantly.