Required time response of a variable valve actuator equiping a hybrid pneumatic–combustion engine
Bibliographic record
Abstract
This work is a part of a research program that aims to modify a conventional internal combustion engine and turn it into a hybrid pneumatic–combustion engine. The hybrid pneumatic–combustion engine should be able to convert mechanical energy into compressed air and convert compressed air back into mechanical energy. The potential application for the concept is any use of the internal combustion engine where the load oscillates between a negative and a positive value, such as automobiles and hybrid wind diesel systems for remote area power generation. In the first application, during vehicle decelerations, an excess of power occurs, and a negative load could be applied to the engine, whereas during vehicle accelerations, a positive load is applied. In the second application, if the generated wind power is higher than consumption demand, then the load applied to the engine could be negative, and if the generated wind power is lower than consumption demand, then the load is positive. In previous work, we exposed an optimization followed by a fuel-saving evaluation of a new hybrid pneumatic–combustion engine concept that uses a variable valve actuator system. The optimization of the valve actuation was based on ideal thermodynamic cycle modeling, assuming therefore an instant response of the variable valve actuator system. In the present work, a more realistic analysis of the system is provided by taking into consideration the dynamic response of the variable valve actuator system. Variable valve actuators have been widely studied for optimizing performance and fuel consumption of the internal combustion engine, especially in spark-ignition engines. For these engines, it is possible to reduce the pumping losses and to optimize the engine filling by controlling the intake and exhaust valve opening and closing angles, as well as their lifts. However, the variation of valve actuation crank angles required in a conventional internal combustion engine is significantly smaller than the one required in the hybrid pneumatic–combustion engine. This paper describes, through simulation, how the valve time response affects the performance of the hybrid pneumatic–combustion engine and recommends a required valve time response.
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.001 | 0.000 |
| Insufficient payload (model declined to judge) | 0.004 | 0.001 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".