Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

A Numerical Simulation Method for Gas Flow Characteristics in a Rare Continuum

A technology of gas flow and characteristic value, which is applied in special data processing applications, complex mathematical operations, design optimization/simulation, etc., and can solve problems such as limitations

Active Publication Date: 2020-05-22
NORTHWESTERN POLYTECHNICAL UNIV
View PDF2 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Due to the strong nonlinear relationship of the nonlinear coupled constitutive relation equation, the traditional finite volume method is limited to solve the flow conservation equation and the nonlinear coupled constitutive relation model

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • A Numerical Simulation Method for Gas Flow Characteristics in a Rare Continuum
  • A Numerical Simulation Method for Gas Flow Characteristics in a Rare Continuum
  • A Numerical Simulation Method for Gas Flow Characteristics in a Rare Continuum

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0068] Now in conjunction with embodiment, accompanying drawing, the present invention will be further described:

[0069] This embodiment is a numerical method for continuous thinning and uniform flow characteristics, which is specifically divided into the following steps:

[0070] Step 1: Combine figure 1 , it can be seen that the mass conservation equation, momentum conservation equation, and energy conservation equation are deduced from the Boltzmann equation, combined with the H theorem and entropy increase, and the closure of the gas dynamics equation is completed.

[0071] Step 2: Combine figure 2 , for the flow conservation equation:

[0072]

[0073]

[0074] Among them, t represents time, U represents a conserved variable, and F inv (U) means non-sticky item, F vis (U) represents a sticky item, Indicates partial derivation, represents the velocity gradient. ρ represents density, u represents fluid velocity, E represents energy, p represents pressure, ...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

The invention relates to a thin continuous uniform air flowing characteristic numerical simulation method. The method comprises the following steps: introducing a spatial derivative directly associated with a conservation variable when solving a conservation equation of a nonlinear coupled constitutive model, and secondly expressing the conservation variable U and an additional variable S into linear expression of one set of primary functions so as to discretize the conservation variable U and the additional variable S; converting conservation quantity under an original unstructured grid to astandard grid, integrating on a control volume, carrying out each step of iteration to obtain initial values of viscous stress and heat conduction items of a constitutive relation equation, introducing the initial values of viscous stress and heat conduction items of the constitutive relation equation into a nonlinear algebraic constitutive equation set converted to a differential equation initialvalue problem, then carrying out iteration to obtain the viscous stress and the heat conduction items, then returning back and substituting into the conservation equation, determining that the calculation is ended after the specific problems meet the error conditions, and outputting the flowing characteristic of the flow field.

Description

technical field [0001] The invention belongs to the numerical simulation algorithm of computational fluid dynamics, and relates to a numerical simulation method of gas flow characteristics of a thin continuum, which is a numerical simulation of gas flow characteristics based on a non-linear coupled constitutive model of gas dynamics in the field of computational fluid dynamics. algorithm. Background technique [0002] Both continuous and rarefied coupled flows are involved in the calculation of flow characteristics of adjacent space and micro-scale flow, and continuous and rarefied regions cannot be strictly distinguished. At this time, the flow properties of the gas change, and the continuity assumption in fluid mechanics no longer applies. Therefore, it is necessary to develop a numerical algorithm for the flow characteristics of continuous rarefaction coupling aerodynamics to solve the technical problems of predicting the aerodynamics of aircraft in near space and the mi...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Patents(China)
IPC IPC(8): G06F30/20G06F17/12
CPCG06F17/12G06F30/20
Inventor 肖洪何其娇
Owner NORTHWESTERN POLYTECHNICAL UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com