Simulation and Modelling

From the previous results it is reasonable to propose the following device model for a bulk hetero junction solar cell (Fig. 5.17)  

Distance from Front [m] Distance from Front [m] 

The previous section gave an overview of the transport and junction properties of conjugated materials regarding their importance for photovoltaic devices. In this chapter, the bulk heterojunction device itself will be in the spotlight. Device properties will be discussed and evaluated as for classical inorganic solar cells, concentrating on the short-circuit current /sc, the open-circuit voltage Foc, the fill factor FF, and the spectral sensitivity. 

Generally, the operation of a photovoltaic device may be visualized as taking place in three consecutive fundamental steps  

In the active layer of the device, positive carriers (holes) are transported through the conjugated polymer matrix, and negative carriers (electrons) are transported by hopping between fullerene molecules. Importantly, these two 

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In all these examples, the importance of good simulation and modeling cannot be stressed enough. A variety of methods have been used in this field to simulate the data in the cases studies described above. Blander et al. [4], for example, used a semi-empirical molecular orbital method, MNDO, to calculate the geometries of the free haloaluminate ions and used these as a basis for the modeling of the data by the RPSU model [12]. Badyal et al. [6] used reverse Monte Carlo simulations, whereas Bowron et al. [11] simulated the neutron data from [MMIM]C1 with the Empirical Potential Structure Refinement (EPSR) model [13]. 

A drastic departure from nucleation theory was made by Sadler [44] who proposed that the crystal surface was thermodynamically rough and a barrier term arises from the possible paths a polymer may take before crystallizing in a favourable configuration. His simulation and models have shown that this would give results consistent with experiments. The two-dimensional row model is not far removed from Point s initial nucleation barrier, and is practically identical to a model investigated by Dupire [35]. Further comparison between the two theories would be beneficial. 

Matko, D., Karbar, R. and Zupancic, B. (1992) Simulation and Modeling of Continuous Systems, Prentice-Hall. 

Ceccarelli, M. Marchi, M., Simulation and modeling of the Rhodobacter spaeroides bacterial reaction center, J. Phys. Chem. B 2003,107, 1423-1431... 

Yang, W. C., Margaritis, P. J., and Keaims, D. L., Simulation and Modeling of Startup and Shutdown in a Pilot-Scale Recirculating Fluidized Bed Coal Devolatilizer, AIChE Symp. Ser., 74(176) 87 (1978)... 

Domingo, P. and T. Benazzouz (2000). Direct numerical simulation and modeling of a nonequilibrium turbulent plasma. AIAA Journal 38, 73-78. 

An introduction to single-point closure methodology. In T. B. Gatski, M. Y. Hussaini, and J. L. Lumley (eds.), Simulation and Modeling of Turbulent Flows, chap. 6, pp. 243-310. New York Oxford University Press. 

PEFC) stacks, components and entire systems, in off-grid, and grid-connected configurations, with a capacity of up to 100 kW electrical power output. The facility consists of an automated and computerised fuel cell test station, gas analysers, a multi-axial vibration system which is housed in a walk-in environmental chamber (for controlling temperatures, humidity, shocks and vibrations) and ancillary equipment. The data obtained are complementary to and validate fuel cell simulations and models with reference to operation modes, components and system characteristics 1 ... 

Poinsot, T. J., D. C. Haworth, and G. Bruneaux. 1993. Direct simulation and modeling of flame-wall interaction for premixed turbulent combustion. Combustion Flame 95 118-32. 

Performing mathematical analysis, advanced computational simulation, and modeling of detonation of multicomponent mixtures using real chemistry and molecular mixing. 

Mashayek, F. 1999. Simulation and modeling of two-phase turbulent flows for prediction and control of combustion systems. 12th ONR Propulsion Meeting Proceedings. Eds. G. D. Roy and S. L. Anderson. Salt Lake City, UT. 88-95. 

Due to the superposition of two inversionally related half molecules in Fe3(CO), 2, the determination of the arrangement of the carbonyl groups proved a difficult task. In fact, nearly 17 years elapsed before it was successfully solved by a process of computer simulation and modeling.40... 

The most critical parameter for the Basic Protocol is the yield of analyte at the detector. Simulations and models are the best methods to identify the extent of the problem and to determine correction factors. 

The investigations to obtain high lateral resolutions were accompanied by different simulations and models for LAPS devices. Beside generic electrical representations and SPICE (simulation program with integrated circuit emphasis)-based simulations [45,46],... 

Guenther Harsch, From Dice Games to Natural Laws Simulation and Models in Physical Chemistry, VCH, Weinheim, 1985. 

Cheatham TE, III (2004) Simulation and modeling of nucleic acid structure, dynamics and interactions. Curr. Opin. Struct. Biol. 14 (3) 360-367... 

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