Discharge simulation

The solutions sought in the discharge simulation are time periodic and match the normal stable operating conditions in the discharge. Time periodicity in die solutions is driven by the time-varying voltage at die powered electrode. The time periodicity condition is expressed as... 

Figure 2.1. The Urey-Miller Experiment. An electric discharge (simulating lightning) passed through an atmosphere of CH4, NH3, H2O, and H2 leads to the generation of key organic compounds such as amino acids.

Experiments have been performed in which the simple compounds of the early atmosphere were allowed to react under the varied sets of conditions that might have been present on the early Earth. The results of such experiments indicate that these simple compounds react abiotically or, as the word indicates (a, not, and bios, life ), in the absence of life, to give rise to biologically important compounds such as the components of proteins and nucleic acids. Of historic interest is the well-known Miller-Urey experiment, shown schematically in Eigure 1.4. In each trial, an electric discharge, simulating lightning, is... 

Fig. 2. Comparison of gas temperature determined by using the emission of N2(C-B, 0-0) (left) and the emission of CN(B-X, 0-0) (right) from the same emission sp>ectrum measured during the discharge. Simulated spectra are shifted for clarity.

Review of Cooling Water Discharge Simulations Models... 

Industrial cooling water discharge simulations in the Arabian Gulf are frequently carried out with tools such as Cormix [1], GEMSS [2], Mike 21 [3], and 3D SMART [4]. Discharges of cooling water into receiving water bodies are an environmental concern... 

Fig. 8. Effect of temperature on relative discharge performance of a fresh "D"-si2e battery for service on simulated ratio use, 25- Q 4-h/d test for (a) an alkaline—manganese battery undergoing 260 h of service, and (b) a carbon—2inc battery undergoing 70 h of service (22).

This program helps calculate the rate of methanol formation in mol/m s at any specified temperature, and at different hydrogen, carbon monoxide and methanol concentrations. This simulates the working of a perfectly mixed CSTR specified at discharge condition, which is the same as these conditions are inside the reactor at steady-state operation. Corresponding feed compositions and volumetric rates can be calculated from simple material balances. 

Cyclic tests can be perfonned in just a few months to simulate years of fill and discharge cycles. The adsorbent filled ANG tank is repeatedly charged with natural gas to a preset pressure, then discharged through a flow meter to determine the quantity of gas delivered from each cycle. 

In the case of gaseous contaminants, the tracer gas is selected to simu late as well as possible the properties (density, temperature) and momentum of the real contaminant. It is essential to ensure that the tracers arc nontoxic, chemically nonreactive, nonadsorptive on indoor surfaces, and inexpensive. The mixing of the tracer with the actual gaseous contaminant before its release or the release of the tracer with a density near that of the air will improve the validity of the simulation. With tracers, the most difficult task in practice is the relationship of the discharge between the tracer and the real contaminant. Case-by-case techniques to release the tracer are necessary in practice. With tracer gases, the procedure for capture efficiency is described in detail in the European Standard. - The tracer gas concentrations are measured in the exhaust duct for two release locations as illustrated in Fig. 10.108. 

Figure 12-23 shows simulation of time-of-flighl photocurrenl transients at variable temperature for a system containing 0.25 eV traps at a concentration c=3xl0. This translates into orjj= 0.080 eV. The current decays monotonously by several orders of magnitude to finally merge into a plateau followed by a rapid fall-off that reflects discharge of the carriers at the exit contact. This is in accord with experiment [74],... 

Wesolowski EA (1999) Simulation of effects of wastewater discharges on Sand Creek and lower Caddo Creek near Ardmore, Oklahoma. Investigations Report 99-4022. US Geological Survey, Denver, Colorado... 

The simulated FBAC consists of an acrylic main reactor (0.5m-H x 0.5m-W x l.Om-L), an air distributor system, particles feeding system including a feed hopper, a discharging sampler, a bag filter for capture of the elutriated fine particles and, pressure and flow rate measurement systems (Fig. 1). The air distributor system has ten air headers. An individual air header is connected with 5 air nozzles and can regulate the airflow rate. The opening ratio of the distributor is 2.1% and each nozzle has four holes for uniform air supply. To measure the pressure fluctuation at an individual air header, high frequency pressure transmitters were mounted at the approach and the exit headers of the FBAC. 

Liquid flows from an upstream source, at pressure Pi, via a fixed position valve into the tank, at pressure P2. The liquid in the tank discharges via a second fixed position valve to a downstream pressure P3. The tank can be open to atmosphere, closed off to the atmosphere and can work either under isothermal or adiabatic temperature conditions. The detailed derivation of this problem is discussed both by Franks (1972) and Ramirez (1976, 1989). Data values in the problem are similar to those of Ramirez, who also made simulations of this problem. 

As a first attempt to modify the code to be able to run simulations on SiH4-H2 discharges, a hybrid PlC/MC-fluid code was developed [264, 265]. It turned out in the simulations of the silane-hydrogen discharge that the PIC/MC method is computationally too expensive to allow for extensive parameter scans. The hybrid code combines the PIC/MC method and the fluid method. The electrons in the discharge were handled by the fluid method, and the ions by the PIC/MC method. In this way a large gain in computational effort is achieved, whereas kinetic information of the ions is still obtained. 

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