Ramanujam Sekar

6700662, Mar 2, 2004

Jan 22, 2001

09/767104

Sreenath B. Gupta - Naperville IL
Ramanujam Raj Sekar - Naperville IL

The University of Chicago - Chicago IL

G01N 1502

356336, 356338, 356335

An improved instrument and method are provided for particulate characterization in combustion exhausts. An instrument for measuring particles of combustion exhausts includes a laser for producing a high intensity laser pulse. A sample cell receives a combustion exhaust input and the high intensity laser pulse. At least one detector detects a signal generated by particles in said received combustion exhaust input. The detected signal includes laser induced incandescence (LII). Signal conditioning electronics is coupled to the detector and particle data is displayed during transient operation of a combustion engine. Data related to mass concentration, number density, and particle size of particles in the received combustion exhaust input is measured and displayed.

7114858, Oct 3, 2006

Sep 14, 2004

10/940467

Sreenath Borra Gupta - Naperville IL, US
Ramanujam Raj Sekar - Naperville IL, US
Gregory E. Hillman - Chicago Ridge IL, US

The University of Chicago - Chicago IL

G02B 6/36
F02B 19/00
H01S 3/123

385 88, 385 18, 385 25, 385 12, 385 92, 385147, 372 15, 123143 B

A laser based ignition system for stationary natural gas engines, a distributor system for use with high-powered lasers, and a method of determining a successful ignition event in a laser-based ignition system are provided. The laser based ignition (LBI) system for stationary natural gas engines includes a high power pulsed laser providing a pulsed emission output coupled to a plurality of laser plugs. A respective one of the plurality of laser plugs is provided in an engine cylinder. The laser plug focuses the coherent emission from the pulsed laser to a tiny volume or focal spot and a high electric field gradient at the focal spot leads to photoionization of the combustible mixture resulting in ignition.

7699033, Apr 20, 2010

Nov 27, 2007

11/945714

Bipin Bihari - Woodridge IL, US
Sreenath Borra Gupta - Naperville IL, US
Ramanujam Raj Sekar - Naperville IL, US

UChicago Argonne, LLC - Chicago IL

F02B 1/02

123143B, 123143 R

A method and system to distribute high-power laser pulses to create sparks in individual cylinders of a multi-cylinder engine are provided. A laser provides laser output pulses. A distributor includes a linear array of mirrors with a respective mirror associated with one of the laser plugs. Each mirror is operatively controlled to move into a laser beam path to direct individual laser output pulses the associated laser plug for providing spark generation. The system enables correct cylinder firing order for predefined multi-cylinder firing sequences and allows for individual cylinder timing variation.

56408455, Jun 24, 1997

May 2, 1995

8/433219

Henry K. Ng - Naperville IL
Vincent J. Novick - Downers Grove IL
Ramanujam R. Sekar - Naperville IL

The University of Chicago - Chicago IL

F01N 318

60274

A NO. sub. X control system for an internal combustion engine includes an oxygen enrichment device that produces oxygen and nitrogen enriched air. The nitrogen enriched air contains molecular nitrogen that is provided to a spark plug that is mounted in an exhaust outlet of an internal combustion engine. As the nitrogen enriched air is expelled at the spark gap of the spark plug, the nitrogen enriched air is exposed to a pulsating spark that is generated across the spark gap of the spark plug. The spark gap is elongated so that a sufficient amount of atomic nitrogen is produced and is injected into the exhaust of the internal combustion engine. The injection of the atomic nitrogen into the exhaust of the internal combustion engine causes the oxides of nitrogen to be reduced into nitrogen and oxygen such that the emissions from the engine will have acceptable levels of NO. sub. X. The oxygen enrichment device that produces both the oxygen and nitrogen enriched air can include a selectively permeable membrane.

56495170, Jul 22, 1997

Sep 18, 1996

8/710520

Ramesh B. Poola - Woodridge IL
Ramanujam R. Sekar - Naperville IL
Roger L. Cole - Elmhurst IL

The University of Chicago - Chicago IL

F02B 2300

123585

An air supply control system for selectively supplying ambient air, oxygen enriched air and nitrogen enriched air to an intake of an internal combustion engine includes an air mixing chamber that is in fluid communication with the air intake. At least a portion of the ambient air flowing to the mixing chamber is selectively diverted through a secondary path that includes a selectively permeable air separating membrane device due a differential pressure established across the air separating membrane. The permeable membrane device separates a portion of the nitrogen in the ambient air so that oxygen enriched air (permeate) and nitrogen enriched air (retentate) are produced. The oxygen enriched air and the nitrogen enriched air can be selectively supplied to the mixing chamber or expelled to atmosphere. Alternatively, a portion of the nitrogen enriched air can be supplied through another control valve to a monatomic-nitrogen plasma generator device so that atomic nitrogen produced from the nitrogen enriched air can be then injected into the exhaust of the engine. The oxygen enriched air or the nitrogen enriched air becomes mixed with the ambient air in the mixing chamber and then the mixed air is supplied to the intake of the engine.

60558083, May 2, 2000

Jun 22, 1998

9/102232

Ramesh B. Poola - Woodridge IL
Ramanujam R. Sekar - Naperville IL

The University of Chicago - Chicago IL

F01N 300

60274

An emission control system for reducing total particulates and NO. sub. X emissions from the exhaust of a diesel engine includes an air supply system that supplies oxygen enriched air to an air intake of the engine. The air supply system may include a selectively permeable air separating membrane device for producing the oxygen enriched air. In order to effectively utilize the increase in the concentration level of oxygen in the intake air, the amount of fuel being supplied to the diesel engine also is increased at a minimum in proportion to the increased concentration level of oxygen in the intake air. The increase in the amount of such fuel being supplied to the diesel engine can be adjusted by an electronic fuel injection system used on such diesel engines. In addition, the electronic fuel injection system is used to retard the injection timing of the engine.

56366191, Jun 10, 1997

Feb 7, 1996

8/598029

Ramesh B. Poola - Woodridge IL
Ramanujam R. Sekar - Naperville IL
Kevin C. Stork - Chicago IL

The University of Chicago - Chicago IL

F02B 2300

123585

An oxygen-enriched air intake control system for an internal combustion engine includes air directing apparatus to control the air flow into the intake of the engine. During normal operation of the engine, ambient air flowing from an air filter of the engine flows through the air directing apparatus into the intake of the engine. In order to decrease the amount of carbon monoxide (CO) and hydrocarbon (HC) emissions that tend to be produced by the engine during a short period of time after the engine is started, the air directing apparatus diverts for a short period of time following the start up of the engine at least a portion of the ambient air from the air filter through a secondary path. The secondary path includes a selectively permeable membrane through which the diverted portion of the ambient air flows. The selectively permeable membrane separates nitrogen and oxygen from the diverted air so that oxygen enriched air containing from about 23% to 25% oxygen by volume is supplied to the intake of the engine.

55266410, Jun 18, 1996

Feb 18, 1993

8/019102

Ramanujam R. Sekar - Naperville IL
Lyle O. Hoppie - West Bloomfield MI

The University of Chicago - Chicago IL

F01N 308
B01D 5356
B01D 5392

60274

A method of reducing oxides of nitrogen (NO. sub. X) in the exhaust of an internal combustion engine includes producing oxygen enriched air and nitrogen enriched air by an oxygen enrichment device. The oxygen enriched air may be provided to the intake of the internal combustion engine for mixing with fuel. In order to reduce the amount of NO. sub. X in the exhaust of the internal combustion engine, the molecular nitrogen in the nitrogen enriched air produced by the oxygen enrichment device is subjected to a corona or arc discharge so as to create a plasma and as a result, atomic nitrogen. The resulting atomic nitrogen then is injected into the exhaust of the internal combustion engine causing the oxides of nitrogen in the exhaust to be reduced into nitrogen and oxygen. In one embodiment of the present invention, the oxygen enrichment device that produces both the oxygen and nitrogen enriched air can include a selectively permeable membrane.