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PaoPien
Washington DC
Interests: Solving problems
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The internal combustion engine requires a new operating cycle because existing cycles do not satisfy the law of conservation of energy.
Applying the law of conservation of energy can greatly simplify the improvement of the internal combustion engine. Since p2V2/U2 = p1V1/U1 and p2/p1 = (V1/V2)k, therefore U2/U1 = (V1/V2)k-1. Because U and V are state variables, U2/U1 = (V1/V2)k-1 is an equation of state. For more transparency and better understanding, a state is denoted by two state variables U and V instead of a numerical number. This equation of state ensures that compression work done by the moving piston compresses cylinder volume from V2 to V1 is transformed into equal internal energy U increase and vice versa. For more transparency and better understanding, a state is denoted by two state variables U and V instead of a numerical number. To demonstrate that utilizing this equation of state alone, the thermal efficiency of a GDI engine can be quickly calculated as follow. A compression stroke of a GDI engine begins from state (U1, V1) with U1 = 95.73 (cvT1) BTU, V1 = 15.6 ft3, and p1 = 14.7 psia and ends at state (U2, V2). With a assumed compression ratio of 9.0, V2 = 15.6/9.0 = 1.733 ft3, U2 = U1(V1/V2)0.4 = 230.5 BTU, T2 = T1(V1/V2)0.4 = 749.0o K, and p2 = p1(T2/T1)1.4/0.4 = 318.7 psia. An entire compression stroke increases internal energy only by 134.8 (230.5 – 95.73) BTU. It is desirable to double the cylinder gas density by extending the compression stroke from 1.733 to 0.867 ft3 and adding heat energy Q simultaneously with the extended compression stroke with U3 = U2 + U2(V2/V3)0.4 + Q. As a result, cylinder air density is doubled and the expansion ratio of 18.0 (15.6/0.867) is obtained. For preventing NOx formation, V3 is limited to 650 BTU to limit the combustion temperature to 2112o K. An expansion process from state (U3, V3) to state (U4, V1) reduce U3 to U4 with U4 = U3(V4/V3)0.4 = 204.6 BTU. Indicated thermal efficiency is equal to (U3 - U4)/U3 = 68.5%. Because of very high compression temperature in the combustion chamber, all combustible substances are completely combusted without engine out emissions. By limiting U3 to 650 BTU with T3 (U3/cv) = 21120 K, formation of NOx is prevented. This is an innovative approach to achieve improved efficiency and very-low emissions.
A reciprocating internal combustion engine with a high compression ratio of say 18.0 and burning fuel per cycle before the moving piston reaches the TDC and limiting the combustion temperature below the critical temperature of NOx formation can achieve a indicated fuel conversion efficiency (IFCE) of 68.5% without the need for aftertreatment. Therefore, there is no need for electrification or hybrid engine system.
Existing compression ignition engine can be easily modified to achieve the high performances by stripping all inlet boosting and aftertreatment equipments and injecting all fuel per cycle before the moving piston reaches TDC regardless at what rate the fuel injection takes place. Therefore any automobile manufacturing company can do the modification. The owner of the modified automobile can immediately cut the operating cost to less than one half. Running the vehicle at a fuel equivalence ratio less than 0.30, the modified vehicle could last for decades. Our nation’s automotive industries can be reduced to a small fraction of its current capacity. The new engine can be used to generate electricity locally without the need for it to be transmitted through the electric grid and it can run on fossil fuel, natural gas, bio fuel, or any other fuel that is locally available. The most important of all, the new engine requires no change in nation’s infrastructure.
By stripping all inlet boosting and aftertreatment equipments and injecting all fuel per cycle before the moving piston reaches TDC regardless at what rate the fuel injection takes place. Therefore any automobile manufacturing company can do the modification. The owner of the modified automobile can immediately cut the operating cost to less than one half. Running the vehicle at a fuel equivalence ratio less than 0.30, the modified vehicle could last for decades. Our nation’s automotive industries can be reduced to a small fraction of its current capacity. The new engine can be used to generate electricity locally without the need for it to be transmitted through the electric grid and it can run on fossil fuel, natural gas, bio fuel, or any other fuel that is locally available. The most important of all, the new engine requires no change in nation’s infrastructure. I am already 98 years old and have no means to test the new engine. It is hoped that one of the reader would carry out the engine experiment.
At 0.3 fuel equivalence ratio, the combustion temperature is only 2112 degree K and NOx formation is prevented. High compression ratio is to have high expansion ratio such that a very high indicated fuel conversion efficiency can be obtained. The combustion temperature is only 2112 degree K greatly lower the heat loss. High compression temperature with long combustion duration will completely eliminate engine out emissions including NOx and can operate on any liquid fuel. The new engine has the benefit of low temperature combustion (LTC) throughout its operate range. A BFCE greater than 0.60 is achievable.
Would you please modify your testing engine by removing the inlet boosting and after treatment equipments and change the compression ratio to 18.0 and starting the combustion process at 0.973 ft3 combustion chamber volume before the moving piston reaches TDC. Then run your engine at a load of 0.3 fuel equivalence ratio. Measure and record the fuel consumption and engine out emissions. You could achieve brake fuel conversion efficiency (BFCE) greater than 0.60 with minimal engine out emissions.
Instead of predicting the combustion chemical reaction rate, would it be simpler to increase the combustion time duration? I have developed a new combustion process which lasts one third of compression and expansion strokes. If anybody is interested, I will be more than glad to send you my new combustion process.
Engineer-poet Even through this site is not run by the US department of Energy, it should not prevent us to offer our solution to increase engine fuel efficiency and reduce engine out emissions.
Engineer-poet, My comment was intended to ask DOE to redefining the scope of the final solicitation. If I have troubled you, please accept my apology and favor me with your critical evaluation of my two-stage CVCE combustion process and my CI-CVCE RICE.