KIMAT ENGINE

By Dae Sik Kim
Kimat Lab
Newton, MA

KIMAT ENGINE is a new type of internal combustion powerplant (ICP) for a mobile application and is the latest item of my automotive engineering efforts of last seventy years. I invent and solve real engineering problems rather than make more work for full employment, which all societies and Governments want.

Early, the invention and development of Cold Cranking Simulator, USP 3,350,920, taught me the cold starting of an engine, Rheology of multi-grade crankcase oils, a better understanding of lubricating an engine and how U.S. Auto and Oil industry worked in 1964.

In October of 1966, I was asked to formulate a plan for building and to build a low polluting engine by ESSO (presently EXXON-MOBIL) Research & Engineering Company in Linden, New Jersey. The target exhaust emission levels were 45 ppm (parts per million) of HCs (Hydrocarbons), 0.3 % of CO (Carbon Mono-Oxide) and 115 ppm of NOx (Oxides of Nitrogen) by the Composite Seven Mode California Test Cycle. These values corresponded to 1.0 of HC, 7.0 of CO and 0.5 of NOx in grams per mile by the newer Federal Test Cycle. Except comparable performance and durability of 1967 production cars and a reasonable added initial/maintenance cost, no other requirements were asked. The project was funded $6 million for three years. New California Air Resource Board asked for the levels and Detroit refused. We made and sold the gasoline.

Three approaches were selected.
1. A “quick ‘n clean” minimal modification of a production engine to meet the target,
2. An add-on catalytic treatment of the exhaust gas from a production engine, and
3 A new, simpler, cheaper, safer, cleaner, and more responsive powerplant for the future transportation based on the best available technology at that time.

For the first approach, I used a 1967 GM Chevy Impala with a 283 CID (cubic inch displacement) V8-engine for the base car, a rich operation and exhaust gas re-circulation for the NOx control and a synchronized air injected thermal reactors for HC and CO control. The modifications are described in U.S. Patents 3,641,767; 3,643,425; and 3,643,640. The detailed experimental results of Synchro-Thermal Reactor System (STRS) were given in SAE 700147. The test car was built in two months and run 60,000 miles on New Jersey Turnpike without any repair except replacing two thermo–couples. The emission was reduced to 8 % (20% more than the target). The estimated OEM cost was about $100.00. The system was duplicated on 1967 Chrysler Satellites.

In the second approach, a slightly rich operation and catalytic reduction were used for NOx control. For HC and CO, air injection and catalytic oxidation were followed. Variety of catalysts, bed arrangements, and single bed of mixed catalysts were tried. However, slow warm-up, high back pressure, poor durability and too strict fuel induction requirements posed difficulties in meeting the target. The results of this approach were published in SAE 710014 and 730567.

Personally, the impending disaster in New England from the combined effects of the politically invisible Lead Oxide, a potent neurotoxin to children’s brain, from our leaded gasoline and the acidifying surface water by the Sulfur Dioxide from Mid-Western coal powerplants was far more urgent than the visibly annoying smog in LA Basin. Obviously, the exhaust manifold reactors which were provided by DuPont, a Tetraethyl-Lead maker, can

use leaded fuel. Convincing Auto Industry, especially Chrysler who was our partner on the emission control effort, the merits of slow stepwise reductions of emissions with catalysts was not very hard, as we already solved their “unsolvable” problem. We asked the concerned elders of Auto Industry to ask us to remove it and Government banned the leaded gasoline in 1972. Fortunately, the timely developments of Titania Oxygen sensor, Pt catalyst, and on-board computer improved and helped the second approach as you know.

For the last approach, a tiny portion of the saved fund was spent to prove the utter irrationality of the conventional peak-power driven ICE systems. SAVE (Stored Air Vehicle Experiment) was conducted and is described in Report No.RL-6LD-70 PRODUCTS RESEARCH DIVISION, ESSO R & E Co. and USP 3,513,929 and the related six foreign patents.

Briefly, a fully equipped 1967 Oldsmobile Tornado gave about 9 miles per gallon for repeated 7 mode California Test Cycles. When the power train and rear/side seats are replaced with a TURBONIQUE impulse turbine on rear wheel drive and a small V-6 engine with an air compressor and tanks, the same runs gave about 15 mpg. SAVE was an air-hybrid turbine driven car. When the Director mangled the rear axle, both half shafts, on the Clayton dynamometer, SAVE was terminated. Without a slippage of the wheels on the drum, the stall torque of the turbine was too much.

SAVE was a simple stored energy driven car built with “off the shelf” hardware but was totally unfit for a vehicular use. The use of the air as the second working fluid for the energy storage required a completely new set of hardware and the heat loss. It required a large storage volume, which the structural members of a vehicle can not provide. Also, the pollution from the compressor lubricant was a problem. However, SAVE have shown us the real problems of the ICEs as the dominant powerplant and that they are not fit to run on the road in a real traffic.

After inheriting all rights to this system and its future improvements from Esso R&D Co. in April of 1971, it was disclosed to Chrysler Corp. in September of 1971. Similarly, it was disclosed to the US Government, National Academy of Engineering, GM, Ford, and others in Auto industry. The defective patent USP 3,672,160 was issued in 1972. Finally, it was proposed at Conference on Basic Research for Automotive Technology in Boston on Feb. 13 and 14, 1979. An effort was made to improve the new engine component, capacitive heat storage and HEAT SYPHON which was discovered during my dissertation work at the Ohio State University. For their wider uses, three related devices, USP 5,560,350; 5,547,640 and 5,632,210, are patented and developed.

THE ENGINEERING PROBLEMS TO SOLVE

All engines need starting, which ranges from an operator’s pull to another smaller engine with its own starter. Also, it needs a physically or chemically stored energy, hardware, and a working medium. Usually, the engine’s shaft-work is converted into the stored energy with an added equipment and the unavoidable conversion loss as heat. When a starter is a part of the engine for restarts, it becomes a dead weight in a mobile application. An electric motor with a charged battery or an air motor with a compressed air in a tank are used for cars and trucks. Sometimes, these stored energies are used for other vehicular needs, such as lights and brakes.

All physically stored energy, such as in a wound spring, spinning wheel, pumped up water, or compressed gas in

a tank loses its potential, the driving force, as it is used. Unlike them, a chemical energy keeps its potential to the last molecular reaction. Unlike the exhaust gas (safe for the Biosphere) from combustion of HCs (the best packaged Hydrogen), use of electrons from a charged battery for transportation has four fundamental strikes.
1. Electro-chemical reaction occurs in the two-dimensional electrodes/electrolyte interphases and the rates of ion and mass transports to and from the surfaces are finite/limited.
2. Electron flow needs metal conductor and magnetic flux needs metal core to push or pull.
3. Battery must carry all reactants, reaction products, electrodes, and electrolyte in a safe container. These dead weights replace paid cargo and passengers, especially in an air travel.
4. Battery must be recharged or replaced in few minutes with the electricity from a truly sustainable power source, such as a Batch Thermo-Nuclear Reaction, which I proposed in 1960.

To avoid the wasteful restarts, an engine and the attached rotating parts are idled (rotated at a slower speed) by throttling (intentionally choking) while no traction work is needed. The Idling and the effort to get to the operating speed waste fuel/energy as engines are very inefficient at low rpm. A flywheel with its stored energy helps to sustain a smooth idling but is a dead weight.

In a conventional directly driven peak power system, the engine must convert the portable energy (fuel) into the large peak shaft power every time, rather than use a peak size prime mover. The engine and the transmission must be large enough to meet the peak transient requirements and the loss on the road and in traffic. Since the operational range (speed and torque) of an engine differ from those of the vehicle in traffic require, an interface which modify and transmits the power is needed. Although modern automatic transmissions with a torque converter eliminated the shifting and clutching by an operator and improved traction of the vehicle, the rapid transients of the engine during ac/deceleration were not eliminated. Conversions of the rotational power into viscous fluid power and the viscous flow waste energy.

Finally, for all tools, its size must match that of its task to be efficient. A mismatch and complexity cause inefficiency. In the past hundred years, however, automotive engineers kept increasing the size of engine just to boost its peak power to improve the acceleration performance of a directly driven car as four-stroke gasoline engines have high HP/weight and are very easy to scale-up. This mismatch caused more severe transients in the combustion reaction, more emission, more wasteful part throttle operation, more frictional loss, and more dead weight. To improve the performance, some mechanical and operational modifications, such as multiple valves, complex valve timings, and super charging are added for a little effect. Recent regulatory requirements added even more hardware and operational complexity to an engine.

In my USP 3,672,160, some solutions to the above cited prior arts are proposed. However, the FIG. 2 has a major defect which makes the engine inoperable. A carrier gear which is missing should drive the wheel gear 51. In general, the proposed system is mechanically too complex and requires too high Octane to be practical.

Before we rush into EVs which are as irrational as directly driven peak systems are, we should solve the real problems. We live on the surface of the Earth like any other animals who exhale CO2. We have only 92 available elements and HCs are the best proven packaged Hydrogen. Engineering is not a Religion but makes tools which help to solve societal problems. Let’s give more time to US, HUMAN, to find better tools to govern ourselves and relate to others. We recycle CO2 with fast-growing plants everywhere and make the whole EARTH greener as the NATURE have done before.

SOLUTIONS

KIMAT ENGINE is a planetary gear based and a stored exhaust gas assisted internal combustion powerplant (ICP) for a mobile application. Mechanically, the sun gear of the planetary gear system is connected to and driven by a variable torque drive turbine, the prime mover, its ring gear is connected to and turns an air compressor, the power sink, and its carrier gear turns the wheels, the output. This simple arrangement of the three functional components frees its planetary gears, provides a degree of freedom between the turbine and the compressor, and allows capacitive storages of the compressed air before and the hot pressurized exhaust gas after the internal combustion process in a staged combustor. KIMAT ENGINE eliminates many old parts (starter, transmission, torque converter, intake/exhaust systems, valve train, and accessories), processes (combustion in the cylinders, idling and throttling), and the entropic losses (cooling, pumping and viscous dissipation) and improves the control, mileage, emission, safety, and performance of the vehicle with fewer moving parts, less weight and least costs.

In KIMAT ENGINE, the ambient air is compressed by a multi-cylinder piston compressor and heated in a staged substantially homogeneous combustion. The hot exhaust gas turns the drive turbine by expanding or is cooled and stored in the tubular structural frame and the semi-flexible functional parts such as a front bumper, a hinged canard, or a wing. The gas to the storage heats a ceramic honeycomb with a very large surface area to the high temperature near the entrance, the hot end. It drops to the ambient temperature at the cool end before exits to the tank(s). On its return trip to the turbine, it reheats itself to the original high temperature and maintains S-shaped temperature profile across the honeycomb. As the gas accumulates in the tank(s), the pressure rises, and the heat accumulates in the ceramic. The profile shifts towards the cool end, vice versa. This is the most efficient way to store / recover energy for repeated short runs. Obviously, after a prolonged rest, like an overnight parking, some/most heat in the ceramic will dissipate but the cool gas can power many starts or move the vehicle as the expanding gas picks up some of the dissipated heat from the ambient. A new start and the following warm-up restore the profile. An over-heating at the cool end is prevented by sending some compressed air to the tank(s) from the crankcase/compressed air tank. The condensed water at the cool end returns with the returning exhaust gas or is used for drinking or making up.

In other view, KIMAT ENGINE is a drive turbine engine, an advanced free turbine engine for auto. This new arrangement with the capacitively stored hot pressurized exhaust gas, the single drive turbine, the planetary gear system, and the piston type compressor solves all shortcomings (the hesitation, high-speed idling, poor milage, low pressure ratio, high NOx, and high temperature metals) of the Chrysler free turbine cars. KIMAT ENGINE takes a short block, piston rods, crankshaft, and a new flat cylinder cover/head and flat top pistons with new disk valves for a new compressor. All other parts of the old engine/power train are discarded. The new output Brake HP is nearly proportional to the rpm and is more than doubled that of a four stroke. As in typical small Diesel engines, the single stage piston can easily provide over 20 bar of compression (4-5 bar in Chrysler) for a wider speed range and is an ideal power sink. The drive turbine with high stall torque responds faster than any known prime mover. No hesitation. No idling.

KIMAT ENGINE needs no separate working medium for the energy storage as the air in SAVE nor converts its energy five times to store as the electro-chemical energy in a battery of hybrid EV. The stored hot gas provides a larger peak power for acceleration of a car or take-off of a plane. Simply, injecting more fuel before or/and after the turbine boosts the peak power/thrust even more but it requires a high temperature metals for the turbine and causes very high emissions.

The cool stored exhaust gas and/or the compressed air inflates safety air bags without exploding Azide, steers, brakes, air–conditions by a simple expansion, and concentrates Oxygen by pressure swings (ad/de-sorption cycle) high in the sky without costly hardware nor idle loss. The optimum size compressor prevents a sustained over-speeding. The flexible front bumper prevents or minimizes the damage in a head-on collision on the ground. On a utility, service, or construction truck, KIMAT ENGINE powers simple and efficient air tools. A

big vehicle provides proportionately larger structural and bumper storage volume without added (dead) weight.

The planetary gear system gives a simple automatic transmission, regenerative braking, and the speed reduction between the high-speed turbine and the low-speed compressor. Unlike in Brayton cycle engines, where the injected fuel controls the turbine inlet temperature and the output power, in KIMAT ENGINE, the driver controls the torque of the turbine directly based on the driver’s sensory feedback. A portion of the torque automatically powers the compressor and maintains the full storage/operating pressure. The compressor rests when the tanks are full. The inlet turbine temperature is set to 2K-degree F. to avoid NOx formation and high temperature metals. The pressure is the operating variable for the storage and is optimized by an on-board computer based on the speeds of the turbine, the compressor, the wheels, the ambient, and the road condition. The distributed storage tank(s) is partitioned for an emergency reserve set-aside or for a finer control of the engine and vehicle dynamics by changing the capacitance. For a car, storage of 5 – 10 cubic foot (5 -10 HP-min) lets the driver slow down or stop the vehicle abruptly with a little effect on the compressor or the combustion reaction as in a human/animal locomotion system.

For the emission control, the staged-combustion processes of a vaporized fuel keep the top local temperature near that of the turbine inlet and avoid the formations of particulates or NOx. A perforated ceramic tube reactor can hold static mixing vanes or catalysts, if needed. KIMAT ENGINE can burn any vaporized fuel and has no Octane nor Cetane requirements. The Synchro Thermal Reactor System already proved that the two-stage combustion can meet any reasonable future targets in g/mile except ZERO which is an abstract reference point not physically real. Pine trees in LA basin emit HCs and lightening and decaying organics emit NOx. Unlike EVs, KIMAT ENGINE cleans the polluted ambient air as the STRS cleaned the air in the ESSO’s garage to <8 ppm HC.

KIMAT ENGINE provides a very high fuel efficiency, higher than Diesel Engines can, by the high turbine inlet pressure and the resulting low exit gas temperature and by the reductions of the entropic losses, cooling, and dead weight. KIMAT ENGINE needs no new material. Except the capacitive storage of hot exhaust gas, every component of KIMAT ENGINE were known and used in the mobility industry for the last sixty years and more.

Finally, KIMAT ENGINE is the third approach and is a partial but a real solution to Global Warming.

A Toyota Prius under modification should shed a half of its weight and give 100 mpg, 0-60 mph in 5 seconds. KIMAT ENGINE (1+HP/Pound) powered FLYING CARS should reduce the traffic and commuting problem with a minor modification of the existing highway.

NOTE

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