Timothy Murray

Massachusetts Institute of Technology

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Mark Jeunnette

University of Auckland

Victor Lesniewski

Massachusetts Institute of Technology

Alison S Greenlee

IIT@MIT

James W. Fleming

The Francis Crick Institute

James R. Warner

Ford Motor Company (United States)

Clarence Whitehurst

United States Naval Research Laboratory

Zachary Burger

Johns Hopkins Medicine

V Amos G. Winter

Massachusetts Institute of Technology

James Pakko

Ford Motor Company (United States)

Bradley A. Williams

United States Naval Research Laboratory

Cooperative Institutions

Massachusetts Institute of Technology

United States Naval Research Laboratory

Ford Motor Company (United States)

Naval Research Laboratory Chemistry Division

Ford Motor Company (France)

IIT@MIT

United States Department of the Navy

The Francis Crick Institute

Nova Research Company (United States)

Heidelberg University

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The Effect of Ash Accumulation on Gasoline Particulate Filters: A Comparison Between Laboratory and Field Aged Samples

James H. Jorgensen Timothy Murray Alexander Sappok Victor Wong Christoph Börensen

Stringent regulations worldwide will limit the level of particulate matter (PM) and particle number (PN) emitted from gasoline engines. Gasoline particulate filters (GPFs) present one strategy for meeting PM and PN limits over the full operating range of the engine. Over time these filters accumulate incombustible ash, increasing system pressure drop and adversely effecting engine performance. The effect of aging as a result of ash accumulation is examined over the full lifetime of gasoline particulate filters, using a novel accelerated aging system. This system utilizes a gasoline combustion chamber into which lubricating oil is injected simulating combustion in the cylinder — the primary source of ash. This report details the construction and validation of this system.

Gasoline direct injection

10.1115/icef2014-5473

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The effect of lubricant derived ash on the catalytic activity of diesel particulate filters

Timothy Murray

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Extinguishment and Burnback Tests of Fluorinated and Fluorine-free Firefighting Foams with and without Film Formation

Bradley A. Williams Timothy Murray Chris Butterworth Zachary Burger James W. Fleming

The fire extinguishment and burnback performance of three foams were tested on four low flash point fuels: gasoline, commercial grade heptane, iso-octane (2,2,4-trimethylpentane), and methylcyclohexane. The final three fuels have flash points in a range between -9°C and - 4°C, compared to gasoline which has a typical flash point of -40°C. Gasoline and heptane represent, respectively, the current and the possible future fuels for the MilSpec qualification test for AFFF. Iso-octane and methylcyclohexane were chosen because they have similar flash points but different surface tensions; AFFFs have difficulty forming film on iso-octane but can easily form film on methylcyclohexane. We observed that the AFFFs had diminished fire extinguishment performance with fire extinction times of 5 to 12 seconds longer in cases where they could not form film. The non-fluorinated foam performed as good as or better than the AFFFs on iso-octane. Significant differences were found between fuels in burnback performance (the time for fire to spread across a foam-covered pool). These fuel differences in burnback were consistent for all three foams studied, and did not correlate with fuel flash point or film formation. Other properties of the fuels, and their interaction with foam components, must be responsible for the differences in fire suppression performance. The rate of fuel passage through the foam layer measured in laboratory studies correlates with burnback performance.

Flash point

Extinguishment

Flammable liquid

Methylcyclohexane

Octane rating

Heptane

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Design and Testing of a Low-Cost and Low-Maintenance Drip Irrigation Filtration System for Micro-Irrigation in Developing Countries

Alison S Greenlee Timothy Murray Victor Lesniewski Mark Jeunnette Amos G. Winter

The cylindrical filters presently used in <1000 m2 drip irrigation systems are frequently clogged, increasing pressure loss and lowering the flow rate through the filters. This work investigates the mechanisms for this clogging and proposes an alternative filtration design that would enable both more reliable and lower maintenance filtering. This proposed system is compatible with existing drip irrigation systems and could be made inexpensively with plastic bottle manufacturing equipment. To compare the proposed design to off-the-shelf options, a drip irrigation test setup was built to measure the pressure loss across different filters as particles accumulated. These experiments confirmed that pleated cartridge filters, with high effective surface area, incurred lower pressure losses than cylindrical filters. These tests revealed that the greatest reason for clogged performance was that filtered particles (not the cartridge filter itself) eventually restricted the flow of water through the system. This inspired the redesign of the filter housing such that the housing extended far below the filter, providing a catch basin away from the filter for the particles to settle. Fixing the filter independently of the bottom casing significantly improved the overall performance of the filtration system, reduced the maintenance requirement necessary from the user, and would enable inexpensive manufacturing via blow molding. This paper experimentally demonstrates that the cartridge filter inside the redesigned housing can filter out over 2 kg of sand while maintaining less than a .03 bar pressure drop across the filter at a flow rate of 25 l/s.

Clogging

Cartridge

Filtration (mathematics)

Pressure head

Hydraulic head

10.1115/detc2014-35351

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DELIVERING A LOW-COST, RELIABLE DRIP IRRIGATION FILTRATION SYSTEM FOR MICRO-IRRIGATION IN DEVELOPING COUNTRIES

Alison S Greenlee Timothy Murray Victor Lesniewski Mark Jeunnette V Amos G. Winter

The cylindrical filters presently used in drip irrigation systems frequently clog, increasing pressure loss and lowering the flow rate through the filters. This work investigates alternative filtration strategies that increase the reliability of, and are compatible with, existing systems. To test different filtration strategies, a drip irrigation test setup was built to measure the pressure loss across different filters as particles accumulated. These experiments found that pleated cartridge filters, with high effective surface area, incurred the lowest pressure losses. More significantly, it was observed during these tests that the filtered out particles settled to the bottom of the filter housing when flow through the filter ceased. This inspired the redesign of the filter housing such that the housing extended far below the filter, providing a catch basin away from the filter for the particles to settle. Fixing the filter independently of the bottom casing significantly improves the overall performance of the filtration system and can be inexpensively manufactured via blow molding. This paper experimentally demonstrates that the cartridge filter inside the redesigned housing can filter out over 2 kg of sand while maintaining less than a .03 bar pressure drop across the filter at a flow rate of 25 l/s.

Cartridge

Filtration (mathematics)

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