Charge Compression Ignition Research Articles

Mesofractal Modeling of Biosystems & Organic Spintronics

Mesoscopic modeling of complex systems involves thermodynamic nonequilibrium of discrete scaling. Further from quantum correlation on a chip retrieved quantum nonlinear optics with single photons enabled by strongly interacting atoms. Accompanied by mesofractals as the development of meso & micro size fractal structures is required to mimic various biological systems for various functions. Showed through fluorapatite in gelatin‐based nanocomposite, fractal in DNA knots driven by balance of fission & fusion in mtDNA/mitochondrial DNA mechanism, for optical engines for light energy detection described the proportional integral derivative [PI(D)]‐controller set in microbial cells to HCCI/Homogeneous Charge Compression Ignition.

Strong knocking characteristics under compression ignition conditions with high pressures

ABSTRACTKnocking combustion has been extensively studied in internal combustion engines in order to achieve higher thermal efficiency. However, the inherent mechanism for knocking combustion under homogenous charge compression ignition (CI) conditions has not been fully understood. In this study, the strong knocking characteristics under CI conditions were parametrically investigated through theoretical analysis and rapid compression machine (RCM) experiments, with addressing knocking intensity (KI) limits and autoignition (AI) modes. The characteristic time and energy release concerned with AI were firstly numerically obtained through constant-volume adiabatic conditions. It is found that despite longer ignition delay time within milliseconds and excitation time within microseconds, iso-octane shows almost the same level of maximum explosive pressure and obvious higher energy density compared with n-heptane with low octane rating, indicating the potential of strong knocking occurrence. Then, knocking characteristics were investigated through RCM experiments operated under different thermodynamic conditions for the different octane rating fuels. It shows that strong knocking combustion characterizing super-knock events is observed for both n-heptane and iso-octane. Meanwhile, initial pressure showed greater impact on knocking combustion, manifesting significant increases in KI at high pressures. The influence from initial temperature becomes more obvious for iso-octane fuel at low pressures with long ignition delay time. Finally, the AI modes for different knocking scenarios were qualitatively assessed through Bradley’s diagram, allowing for the uncertainties of hot-spot sizes and temperature gradients. It shows that most AI modes of strong knocking combustion were located in the developing detonation regime, illustrating the possibility of super-knock under CI conditions with high thermodynamic conditions.

Not Even the Kitchen Sink

This article focuses on the increasing commercial application of capillary force vaporization. Possibilities range from fuel oil burners to the sophisticated kerosene heaters that are popular in Japan. A new stove will introduce capillary force vaporizing as a way of atomizing fuel, stepping away from cartridge and metal-tank stoves that dominate the market. Researchers in the United States are also exploring the technology’s suitability to diesel and homogeneous charge compression (HCCI) ignition and engines. A capillary force vaporizer’s ability to vaporize low-volatility diesel fuel at atmospheric temperatures and pressures gives the technology an edge over air-assist or other methods that produce small droplets. A capillary force vaporizer could be applied to a Heel engine in the manifold between turbocharger and intake valves or a vaporizer could be installed in the combustion chamber itself. Jetboil Inc. of Guild, N.H., integrated a pot, burner, heat exchanger, canister, and insulator into a single unit to promote efficient fuel use. As a result, the stove uses less fuel in the field, which is about half that of a conventional pot-and-stove setup that lacks an engineered interface.