scholarly journals A Study on the Efficient Method for the Solution of the Saha Equation in the Numerical Simulation of Capillary Discharge

2017 ◽  
Vol 2017 ◽  
pp. 1-9 ◽  
Author(s):  
Hengzhu Liu ◽  
Cheng Wu ◽  
Fengjiang An ◽  
Shasha Liao

In the numerical simulation of capillary discharge for the Electrothermal (ET) or ET-chemical (ETC) launch system, one needs to solve the Saha equation to determine the composition of plasma for the transport coefficients. This would cause a relatively longer simulation runtime compared with conventional computational fluid dynamics problems. In this paper, the relatively difficult multidimensional problem of solving the Saha equation is transformed into a one-dimensional problem in the simulation of capillary discharge by constructing an iteration equation about temperature. A coefficient is introduced to ensure the convergence of this iteration equation. In order to improve the computational efficiency, this coefficient is further optimized and the methods of setting the iteration initial value dynamically are introduced. Several simulation tests are conducted to study the performance of these two methods. The results show that the simulation runtime could be significantly reduced with the methods presented in this paper.

Author(s):  
Mayank Rakesh ◽  
Paritosh Kumar Rakesh ◽  
Brajesh Kumar ◽  
Satajit Chowdhury ◽  
Atul Kumar Patidar

2012 ◽  
Vol 3 ◽  
pp. 366-374
Author(s):  
Jarosław Wasilewski ◽  
Kryspin Mirota ◽  
Sylwia Peryt-Stawiarska ◽  
Andrzej Nowakowski ◽  
Lech Poloński ◽  
...  

2000 ◽  
Vol 8 (4) ◽  
pp. 211-230 ◽  
Author(s):  
Philip W. Grant ◽  
Magne Haveraaen ◽  
Michael F. Webster

It has long been acknowledged that the development of scientific applications is in need of better software engineering practices. Here we contrast the difference between conventional software development of CFD codes with a method based on coordinate free mathematics. The former approach leads to programs where different aspects, such as the discretisation technique and the coordinate systems, can get entangled with the solver algorithm. The latter approach yields programs that segregate these concerns into fully independent software modules. Such considerations are important for the construction of numerical codes for practical problems. The two approaches are illustrated on the coating problem: the simulation of coating a wire with a polymer.


2014 ◽  
Vol 687-691 ◽  
pp. 679-683 ◽  
Author(s):  
Jun Zhang ◽  
Yong Wu ◽  
Hong Mei Tang ◽  
Chun Ren Tang ◽  
Xian Hua Li

The oil spill will directly affect the measuring accuracy of the gear flowmeter, so use the computational fluid dynamics software to calculate the leakage regulation of the internal gear flowmeter is one of the important things. Based on Pumplinx, when the end clearances of the gear flowmeter were 0um, 10um, 20um, 30um, 40um and 50um, the corresponding numerical analysis of spillage was carried out. From the results of numerical analysis, with the increase of the end clearance, the leakage amplification will also increase. In practical work, we should control the end clearance of gear flowmeter strictly while the gear works normally.


2018 ◽  
Vol 20 (4) ◽  
pp. 393-404 ◽  
Author(s):  
José Galindo ◽  
Roberto Navarro ◽  
Luis Miguel García-Cuevas ◽  
Daniel Tarí ◽  
Hadi Tartoussi ◽  
...  

Zero-dimensional/one-dimensional computational fluid dynamics codes are used to simulate the performance of complete internal combustion engines. In such codes, the operation of a turbocharger compressor is usually addressed employing its performance map. However, simulation of engine transients may drive the compressor to work at operating conditions outside the region provided by the manufacturer map. Therefore, a method is required to extrapolate the performance map to extended off-design conditions. This work examines several extrapolating methods at the different off-design regions, namely, low-pressure ratio zone, low-speed zone and high-speed zone. The accuracy of the methods is assessed with the aid of compressor extreme off-design measurements. In this way, the best method is selected for each region and the manufacturer map is used in design conditions, resulting in a zonal extrapolating approach aiming to preserve accuracy. The transitions between extrapolated zones are corrected, avoiding discontinuities and instabilities.


Sign in / Sign up

Export Citation Format

Share Document