Advanced Combustion Research. at Stony Brook University: What is the Future for Combustion Engines?

Transcription

1 Advanced Combustion Research at Stony Brook University: What is the Future for Combustion Engines? Benjamin Lawler, Ph.D. Engine Combustion Research Group October 24 th, 2018 Advanced Energy Research and Technology Center (AERTC) LIPA Board Meeting 1

2 Presentation Contents Background of Conventional and Advanced Combustion Modes Modeling and Experimental Capabilities at Stony Brook Current Research Projects Future Vision for Engines and a Renewable Grid 2

3 Background Conventional and Advanced Combustion Modes Spark Ignition (SI) has relatively low efficiencies, but generally low emissions Diesel combustion has high efficiencies, but produces NOx and soot emissions Advanced low-temperature combustion modes are the future of combustion Pair the high efficiencies of diesel combustion with near-zero NOx and soot emissions 1 Intake 2 Compression 3 Expansion 4 Exhaust Spark HCCI Ignition (SI) 3

4 Engine Combustion Research Group (ECRG) Started in faculty, 11 PhD students, 4 MS students Interest in advanced combustion concepts and future renewable fuels Biofuels, Natural Gas, or Electrofuels Capabilities with experimental and computational research methods 4

5 Experimental Capabilities State-of-the-art single-cylinder research engines modeled after production engine geometries Engines are fully instrumented with high-speed cylinder, intake, exhaust, and fuel rail pressure sensors, crank shaft encoders, and high accuracy flow meters Custom, in-house LabView ECU/DAQ Allows complete control over the engine operating condition and performs real-time calculations for engine monitoring Industry-standard exhaust gas emissions analyzers measure the CO, CO 2, O 2, uhc, and NOx 5

6 Modeling and Simulation Capabilities 3-D Computational Fluid Dynamics (CFD) Solves the fluid flow during the engine cycle Also solves the combustion chemistry and emissions formation Utilizing 3 High Performance Computing (HPC) clusters and 3 local, high-end workstations Seamless transition between solid CAD models of experimental engines and CFD models System-Level Modeling Vehicle modeling and drive-cycle simulations Thermodynamic engine modeling 6

7 Example CFD Animation of Intake Flow Streamlines 7

8 Active Research Project #1: Single Fuel RCCI Combustion One of the advanced combustion modes uses two fuels to achieve high efficiencies and low emissions Reactivity Controlled Compression Ignition (RCCI) Major drawback for light-duty vehicle applications: requirement of two fuels Single-Fuel RCCI Enabled by Onboard Fuel Reformation DOE Vehicles Technology Office $1.128M - 3 year project A fuel reformer is a catalyst that chemically reacts the parent fuel, changing its autoignition properties Creates two fuels streams for RCCI from one parent fuel Patent filed in

9 Active Research Project #2: Highly Distributed CHP with an FPLA 9

10 Active Research Project #2: Highly Distributed CHP with an FPLA Combined Heat and Power (CHP) offers significant efficiency benefits by not wasting the rejected heat Works for colleges, hospitals, military bases, where there is a high electrical and heating demand Centralized CHP is a challenge for residential neighborhoods because it s difficult to transport heat over long distances 10

11 Active Research Project #2: Highly Distributed CHP with an FPLA As the generator in a distributed residential CHP system, we proposed a Free Piston Linear Alternator (FPLA) Free piston engines do not have a crankshaft and therefore have significantly lower frictional losses Flexible stroke, compression ratio, fuel utilization, and combustion strategy Challenges associated with control of the piston motion 11

12 Active Research Project #3: Thermally Stratified Compression Ignition (TSCI) We invented a new advanced combustion mode that is enabled by Direct Water Injection called Thermally Stratified Compression Ignition (TSCI) Direct Water Injection provides control over the combustion process of a high efficiency, clean-burning, fuel-flexible combustion mode TSCI is one of the most promising advanced combustion modes due to its: High efficiency Low emissions Enhanced controllability Operating range that is as large as conventional combustion modes 12

13 Active Research Project #4: Integrated SOFC + ICE Integrate a solid oxide fuel cell (SOFC) with an internal combustion engine (ICE) to create a system that can achieve 70% electric power efficiency Use the anode tailgas from the SOFC as fuel for the engine to produce additional power The engine supplements the system power and also serves as balance-ofplant for the stack 13

14 Why Engines? With fuel cells and battery electric vehicles constantly threatening to unseat the internal combustion engine (ICE) Why continue researching engines? Improvements to existing hardware systems can have an immediate impact on vehicle fuel economy without the need for infrastructure changes Systems Engineering Viewpoint: Energy density is the highest priority ~x10 Volume Based Energy Density [MJ/L] Mass Based Energy Density [MJ/kg] ~x100 14

15 What about CO 2 emissions and Fossil Fuel Consumption? Advanced Combustion Research at Stony Brook University What about CO 2 Emissions and Fossil Fuel Consumption? The problem is not the engine The solution is to use a different fuel Gasoline vs. Natural Gas Hydrogen Fuel Cell vs. Hydrogen ICE Renewable and Sustainable Biofuels Gasoline like Molecule C 8 C 18, H to C ratio 2.25 Natural Gas, CH 4 H to C ratio of 4 2H H 2 0 CO 2 Absorbed from Atmosphere CO 2 Returns to Atmosphere H 2 + air H

16 Naphthenic Biofuels on Mixing Controlled Combustion Part of an initiative at the Department of Energy to co-optimize engines and fuels Stony Brook will collaborate with RTI International RTI will produce naphthenic biofuel mixtures from loblolly pines SBU will test various surrogate fuel blends and RTI s naphthenic blend in mixing controlled combustion Aromatics Olefins Paraffins DOE Bioenergy Technologies Office (BETO), 3 year $1.48M Started 9/2018 Naphthenes 16

17 Thermally Stratified Compression Ignition Enabled by Wet Ethanol The major drawback of the previous version of TSCI is that it requires a separate direct water injection system (added cost and complexity) TSCI can be enabled by a split injection of Wet Ethanol from a single injection system Completely production hardware for a modern diesel of gasoline engine Wet ethanol is a mixture of water and ethanol Presents the opportunity to save between 8% - 33% of the energy and cost to produce ethanol Pairs a high-efficiency, clean combustion concept that is possible on production hardware with energy savings during the production of a renewable biofuel Provisional Patent filed in

18 What about Electric Vehicles? Hybrid Electric Vehicles (HEVs) allow the engine to operate much more efficiently HEVs are the future! Electric Vehicles (EVs) also have their place in today s society and the future However, EVs are being marketed as a new, clean, and efficient silver bullet for transportation applications, by people who have a financial interest in EVs Are they new? EVs predate engine powered vehicles by 50 years (1835 vs. 1885) Are they clean? The vehicle itself has no emissions after its produced. But the production of electricity has associated emissions, and manufacturing of the battery generates CO 2 emissions that are equivalent to years worth of driving an enginepowered vehicle Are they efficient? The average efficiency of EVs is about ~70%. But EVs get their electricity from the grid, which has a national average efficiency of 33.6%, bringing the well-to-wheel efficiency around 23.5% (70% x 33.6%) How does this compare to an engine-powered vehicle? 18

19 The Efficiency of Internal Combustion Engines The most efficient engine can achieve efficiencies of ~55% Large bore, low speed (90 RPM) marine 4-stroke diesel engine But the type/size engine in a light duty vehicle has a peak efficiency of ~40% However, the average engine efficiency in a conventional vehicle is ~15% Clearly, if the peak is 40% and the average is 15%, then we re not using the engine intelligently The average engine efficiency in some HEVs is ~32% because the electric component allow the engine operate more efficiently 19

20 What about Electric Vehicles? Hybrid Electric Vehicles (HEVs) allow the engine to operate much more efficiently HEVs are the future! Electric Vehicles (EVs) also have their place in today s society and the future However, EVs are being marketed as a new, clean, and efficient silver bullet for transportation applications, by people who have a financial interest in EVs Are they new? EVs date to the late 1800s; they are as old as engine-powered vehicles Are they clean? The vehicle itself has no emissions after its produced. But the production of electricity has associated emissions, and manufacturing of the battery generates CO 2 and particulate emissions that are equivalent to years worth of driving an engine-powered vehicle Are they efficient? The average efficiency of EVs is about ~70%. But EVs get their electricity from the grid, which has a national average efficiency of 33.6%, bringing the well-to-wheel efficiency around 23.5% (70%*33.6%) What if a larger percent of the grid was from renewable energy sources? 20

21 Are there any challenges with Renewable Energy Sources? Intermittency! Solar, Wind, Hydro-electric, Tidal Production might not align with demand There are times when we have more renewable electricity than we can use, and other times when we do not have enough We ll still need controllable load-following and peaking power plants to meet demand We need grid-scale energy storage Batteries not a good option due to cost, reliability and lifetime, and the energy consumed during manufacturing Pumped water/hydroelectric/rail good option if the geography supports it, although the energy density is not great Are there any other grid scale energy storage strategies? 21

22 Fuels Produced from Renewable Electricity Power-to-gas and similar strategies Use renewable electricity directly to produce either gaseous, or liquid fuels Biofuels Use renewable electricity in the fermentation and distillation of starches and sugars Electrofuels Renewable electricity can stimulate microorganisms in microbial electrosynthesis Regenerative Fuel Cell or Reverse Fuel Cell (RFC) Operate a fuel cell in reverse, supplying renewable electricity to produce fuels Can produce all types of methanol, ethanol, butanol, biodiesel, hydrogen, methane, and ammonia in a renewable, sustainable, and potentially carbon-neutral way Potentially use the same distribution and refueling infrastructure we already have A combustion engine operating on a renewable fuel offers an efficient, clean, and sustainable future solution for transportation or power generation An EV would still have the issue of manufacturing and disposal of the battery 22

23 Summary The Engine Combustion Research Group at Stony Brook University was established in 2015 to investigate high efficiency, clean combustion concepts and unique and alternative engine designs Although the public opinion is that engines are antiquated and will not be a part of the future, engines still have room for improvement and will continue to be used to meet the transportation needs of society in the future Projections to 2040 show that 99% of highway vehicles will still have an engine Biofuels (ethanol, biodiesel, biogas, etc.) and fuels produced from renewable electricity (electrofuels, hydrogen, methane, or methanol) provide a future path towards a completely renewable, sustainable, and cost-effective engine-based platform for future transportation solutions 23

24 Thank you Questions? 24