A5086364049- Advanced Combustion Engine Technologies
- Combustion and flame dynamics
- Vehicle emissions and performance
- Heat Transfer and Boiling Studies
- Biodiesel Production and Applications
- Spectroscopy and Laser Applications
- Catalytic Processes in Materials Science
- Combustion and Detonation Processes
- Heat Transfer and Optimization
- Refrigeration and Air Conditioning Technologies
- Advanced Sensor Technologies Research
- Modular Robots and Swarm Intelligence
- Heat transfer and supercritical fluids
- Fluid Dynamics and Mixing
- Image Retrieval and Classification Techniques
- Spacecraft and Cryogenic Technologies
- Advanced Image and Video Retrieval Techniques
- Scientific Computing and Data Management
- Experimental and Theoretical Physics Studies
- Vehicle Noise and Vibration Control
- Cyclone Separators and Fluid Dynamics
- Single-cell and spatial transcriptomics
- Color Science and Applications
- Hydraulic and Pneumatic Systems
- Radiative Heat Transfer Studies
Middlebury College
2024
Argonne National Laboratory
2023
University of Oxford
2000-2019
Brunel University of London
1985-2014
Science Oxford
1999-2001
Engineering Systems (United States)
1987-1993
Instantaneous heat flux measurements have shown that, in the expansion stroke, can flow from wall into combustion chamber, even though bulk gas temperature is higher than temperature. This unexpected result has been explained by modelling of unsteady flows and conduction within side thermal boundary layer. that these effects change phasing flux, compared with which would be predicted a simple convective correlation based on properties. Twelve fast response thermocouples installed throughout...
A review of cycle-by-cycle variations in combustion and early flame histories is used to discuss the origins cyclic spark ignition engines. The hypothesis that are caused by displacement kernel, tested means a phenomenological turbulent entrainment model. model results compared with experimental data, from range operating conditions covers changes in: fuel, air fuel mixture, timing throttle setting. characterized indicated mean effective pressure, maximum rate pressure rise, burn speed....
The influence of swirl on combustion in diesel and spark ignition engines is reviewed briefly, this leads to a resume the measuring techniques. numerous ways analysing data are summarised relations between different parameters presented. Experimental results presented from engine which flow has been measured by hot wire anemometer, paddle wheel torquemeter. performance measurement techniques compared. Further (from engine) illustrate inlet port, manifold entry conditions measurements....
Advances in robotic automation, high-performance computing, and artificial intelligence encourage us to propose large, general-purpose science factories with the scale needed tackle large discovery problems support thousands of scientists.
This work examines the possibility of detecting misfires via measurements angular acceleration engine block. Measurements were taken on a production 4-cylinder which was modeled as single degree freedom torsional oscillator. The torque waveform estimated and compared to calculated cylinder pressure measurements. Further analysis conducted in frequency domain. Results indicate that metrics based low information most reliable, but this is impractical for vehicular applications. accuracy high...
Calculations of the mass fraction burnt as a function time in spark ignition engine have been made by two methods. The simple method assumes that is proportion to total pressure rise due combustion. complex two-zone combustion model, and computes required give observed for each 1° crank angle increment. model allows dissociation, variable gas properties heat transfer from unburnt gases. Notwithstanding substantial differences between models, results are surprisingly close agreement. This can...
This paper investigates a number of new approaches to mass fraction burned analysis for application spark ignition engine combustion processes. The rationale these is retain the simplicity and computational efficiency technique Rassweiler Withrow, but overcome some limitations inherent in standard methods. investigated include use two-zone model determine information about unburned gas temperatures modification Withrow expression incorporate polytropic indices compression expansion....
We have investigated a particular type of fast-response surface thermocouple to determine if it is appropriate use one-dimensional transient heat conduction model derive the flux from measurements temperature. With these sensors, low thermal inertia junctions are formed near by abrasive wear. Using laser excitation, we obtained impulse response commercially available devices. The sensors can vary new created Furthermore, was found deviate substantially and varied sensor sensor. simulated...
This paper investigates a technique of calculating the completeness combustion on cycle- by-cycle basis. The introduces normalized pressure rise due to parameter, ψ describe combustion. parameter is based Rassweiler-Withrow method mass fraction burned and derived from pressure-crank angle record engine. Experimental data were obtained Rover K4 optical access engine analysed with analysis package. A computer simulation was then used model cycle-by-cycle basis, both without parameter....
A phenomenological model of turbulent combustion has been developed and validated against data from wide ranging tests on a Ricardo E6 engine. Most used iso-octane, with range air fuel ratios ignition timings, for at full throttle (with without knock) part throttle. Some were also conducted methanol toluene. The engine performance was characterized by mean coefficient variation (CoV) of: the peak pressure, maximum rate pressure rise, IMEP, burn flame speed measurements. results have to argue...
The three-colour method has been developed in order to turn chromatic information charge coupled device (CCD) camera images of combustion into flame temperature and soot concentration measurements. showed the following advantages over two-colour from which it is derived: only one needed; no further calibration required once response curve known; does not rely on light intensity but ratios between colour components, making easy adapt different operating points with name brightness. results...
Abstract Premixed laminar combustion in closed vessels has been widely used for the determination of burning velocities. A novel multiple burnt gas zone model developed to describe different aspects premixed a spherical vessel. The mixture is divided into and unburnt gases with flame front as discontinuity. Unburnt are assumed be frozen chemical state. However, number zones. For methane–air determine temperature distribution within gas, relationship between pressure rise mass fraction burnt,...
A study of the engine combustion, instantaneous heat transfer and exhaust emissions during warm-up stage has been carried out on a Rover K16 four-cylinder four-valve spark ignition engine. The obtained by an unsteady two-dimensional analysis surface temperature measurements. effect wall these parameters investigated under different load speed conditions. simplified single-zone model used to stage. experimental results show that increasing impact burn duration, in-cylinder transfer,...
This paper first presents an exposition of the theory relevant to quantitative planar laser-induced fluorescence measurements in engine, at a level commensurate with expertise specialist engineer. It is intended provide grounding technique, its theoretical basis, and source references. Second, this design multi-component fuel tracer set that may be used for fluoroscence (PLIF) where time crank-angle resolved knowledge vaporization different fractions required. Such presented shown exceed...
Advances in robotic automation, high-performance computing (HPC), and artificial intelligence (AI) encourage us to conceive of science factories: large, general-purpose computation- AI-enabled self-driving laboratories (SDLs) with the generality scale needed both tackle large discovery problems support thousands scientists. Science factories require modular hardware software that can be replicated for (re)configured many applications. To this end, we propose a prototype factory architecture...
An experimental and theoretical investigation has been undertaken on a viscous flowmeter, with both steady unsteady flow. The flow analysis quantifies the nonlinear effects of entry exit losses, development length compressibility effects. experiments show that pressure drop quadratic response to flowrate, but for practical applications linear approximation will lead an error less than 1%. unsteadyflow it is necessary integrate instantaneous over whole number cycles, in order obtain reliable...
Experimental data were obtained from a Rover K4 optical access engine and analysed with combustion analysis package. Cyclic NO values calculated by mass averaging the measurements fast analyser. The modelled results compared experimental on plots of versus peak cylinder pressure, P max . model achieves its cyclic variability through input experimentally derived burn rates completeness parameter. This is based Rassweiler Withrow method for calculating fraction burned pressure—crank angle...
Heat flux measurement and pressure-based heat release analysis have been performed on a spray-guided direct-injection spark-ignition single-cylinder research engine. A two-dimensional model of the sensor has used to calculate from measured surface temperature. The effects ignition timing, air-fuel ratio, mixture preparation engine investigated at specific operating condition. An thermodynamic simulation code predict gas-to-wall transfer using different correlations. It was found that both...