Best Of
Re: Natural Convection in enclosed container with EDEM particles
Hi Rajani,
Please follow the below steps to access the tutorial using EDEM+ Simlab
1) Click on File--> Help-->Learning Centre , you will navigate to below page
2) Expand Multiphysics and select the below tutorial
Hope this helps to you.
Thanks,
Prasad A
積層厚肉シェル要素で、積層材の破壊指数を出力する方法
はじめに
本記事では、積層厚肉シェル要素 (要素は CHEXA, CPENTA の六面体もしくは三角柱要素、プロパティは PCOMPLS) を使う場合に、破壊指数の出力 (IO 要求カードの CFAILURE) を行う方法を示します。
本記事は、PCOMPLS と MAT9OR を使った積層厚肉シェルモデルの作成ができることが前提で、その後の部分のみお話します。
注)破壊指数と言っても、本当に破壊の計算をするわけではなく、線形静解析の結果に対して、基準値のどれくらいの値になっているかを示すための物なので、破壊指数という名称とは関係なく設計指標など自由に利用できます。
BULK セクション (モデル作り) で必要なこと
厚肉シェル要素で使う MAT9OR には破壊基準値を入力できません。
https://help.altair.com/hwsolvers/os/topics/solvers/os/mat9ort_bulk_r.htm
そこで MAT9OR に MATF を組み合わせて使います。
https://help.altair.com/hwsolvers/os/topics/solvers/os/matf_bulk_r.htm
最低限必要な項目は以下の通りです。材料 ID MID を MAT9OR と同じにしますが、HyperMesh で作業する場合、次のように MAT9OR に MATF を追加するような形になるので、自動的に同じになります。
CRITERIA は基準値の評価方法です。単純な応力、ひずみの他に Hashin などの複合材でよく使われる手法も選択できます。
V1 ~ V9 は、ソリッドですので応力またはひずみの 9成分の評価基準を入力します。選択する評価方法 CRITERIA 次第では、さらに多くのパラメータが必要になります。
I/Oセクション (出力要求)
CFAILURE は破壊指数そのものです。全く応力、ひずみのない状態で 0、基準到達で 1.0 です。CSTRESS, CSTRAIN は積層材向けの応力とひずみの出力要求です。破壊指数が応力系なら CSTRESS, ひずみ系なら CSTRAIN を要求しておくと便利だと思います。
CFAILURE(H3D)=ALL CSTRESS(H3D)=ALL CSTRAIN(H3D)=ALL
例題モデル
UD 材をイメージした、３方向の引張試験モデルを作りました。
材料はこのような特性です。単純な応力成分ごとの基準としました。
破壊基準値はこのようになりました。
0度と 90度は手計算でも行けます。0 度は 方向 1に 100MPa の引張応力なので、呼応する基準値は V0=1000MPa。100/1000=0.1 です。90度は方向 2に 100MPa ですので、V3=50MPa を適用すると、100/50=2 です。
45度の試験では σ12 に 50MPa が出ています。したがって V7=100MPa を適用すると 0.5 となります。
この例題のダウンロードはこちらです。
スーパーエレメントのチュートリアル
概要
本チュートリアルではスーパーエレメントの静的縮退と動的縮退の方法について取り扱います。
スーパーエレメントを使用することで解析時間の削減、構造/形状の秘匿、解析の効率化が可能です。
静的縮退のチュートリアル
- 静的縮退は代数的な代入を通して、線形マトリックス方程式を構造のインターフェース自由度に縮退。さらに、荷重ベクトルもインターフェース自由度に縮退します。これには、点や圧力荷重だけでなく加速度による分布荷重（GRAVとRLOAD）からの荷重ベクトルも含まれます。
- OptiStructで静的縮退を行う方法はDASETとPARAM,EXTOUTを定義します。
- 静解析にのみ使用します。静的縮退では縮退質量マトリックスが近似されるため、動解析は非推奨となります。
静的縮退のモデルを用いた最適化
動的縮退(CMS法)のチュートリアル
- 本手法は、弾性体の有限要素モデルをインターフェース自由度と一組の固有モードに縮退するために用います。
- 結果をマルチボディダイナミクス解析で弾性体として、または有限要素解析でスーパーエレメントのアセンブリを表す外部マトリックスとして使用できます。
- 近似法ですが、質量マトリックスを正しく捉えることができるので動解析で使用されます。
- CMSスーパーエレメント作成時に荷重ベクトルは縮退されません。
テキストとモデルのダウンロード
チュートリアルのモデルとテキストをダウンロードできます。
airframe_section_TUTORIAL_STATIC.hm
airframe_section_OPTIMIZATION.hm
Altair Compose: What’s New in Compose 2023.1
We are thrilled to announce the launch of the latest version of our Altair Compose, expanding the supported libraries in Communication protocols, enhancing existing capabilities and user experience.
Here are some of many highlights of our latest version of Altair compose. for entire list, please visit Compose_2023.1 ReleaseNotes
Communication Library
As part of the Communication library, we now support RestAPI, TCP/IP, UDP protocols in Altair Compose.
REST API’s
REST, or Representational State Transfer, is an architectural style for designing networked applications for communication between client and server in a web-based environment.
Compose’s REST API library provides a standardized way for different systems to interact with each other over the internet via resource-based URL’s and exchange the data in a simple, lightweight, and stateless manner. REST API’s enables clients to interact with server side with standard HTTP methods – GET, POST, PATCH, PUT and DELETE using easy to use OML commands webread, webwrite, weboptions.
The library contains the following commands.
- webread – Read content from URL of web service.
- webwrite – Write content to the specified URL of web service.
- weboptions – various configuration options to set for reading and writing from/to URL.
TCP/IP & UDP
Network protocols like TCP/IP & UDP are now supported to create client & server applications with Read, Write operations.
Supported commands.
- tcpclient – creates a TCP client object
- tcpserver – creates a TCP server object
- udpport – opens a udp port to communicate via udp protocol.
JSON library
JSOM library in Compose OML provides functions to encode and decode JSON data to OML datatypes.
- jsonencode
- jsondecode
*Table describing mapping of JSON with OML datatypes
Enhancements
Plot Assistant
Starting 2023.1, users can use plot assistant for subplots and also specify link axes property between plots.
Along with new subplot capabilities, now Plot commands window is made consistent with the editor, which brings declarative features like color code to identify inbuilt oml commands.
Signal Processing
List of supported signal processing commands was increased in the categories of Generate, Filter, math operations on signals.
PSIM
Along with an ability to run PSIM simulations both Synchronously and Asynchronously, starting 2023.1 users can leverage OML commands to run their Hyperspice and LT spice models.
Commands to Simulate hyper and LT spice models
- PsimSimulate_Hyperspice
- PsimSimulate_LTSpice
OML commands to Create, read, write PSIM Schematic file operations are now supported.
Commands for Schematic File operations
- PsimCreateNewElement
- PsimFileClose
- PsimFileOpen
- PsimFileSave
- PsimGetElementList
- PsimSetElmValue
GUI widgets and Properties
OML has extensive support for creating widgets which includes uitable objects. starting 2023.1, users can leverage uitable object to
- Insert Icons/images in cell widgets.
- ‘columnformat’ property to specify what format does entire column would have.
- char – datatype, left justified
- logical – datatype, center justified for checkboxes
- numeric – datatype, right justified
- cell – datatype, popupmenus with items specified by the cell
- ‘headerformat’ property to specify what format does entire column would have.
- char – datatype, left justified
- logical – datatype, center justified for checkboxes
- numeric – datatype, right justified
- ‘showgrid’ – to specify grid for the uitable object.
Re: How is the drag coefficient determined?
Hi Shinichiro
Please check https://help.altair.com/edem/Bibliography.htm. If you scroll down to 'Lift and Drag Models', there are references of where the equations are taken.
To give a constant drag coefficient, you will have to use API within EDEM to do it. You can take a look at this reference, and modify it a bit to use constant drag: https://community.altair.com/community/en/edem-api-particle-body-force-field-data-coupling-choice-of-drag-models-with?id=kb_article&sysparm_article=KB0122101
Hope this helps.
Thanks,
Jerrin Job
Re: How to use volumetric flow (m^3/s) - outlet boundary condition
First - you shouldn't be using mildly compressible or compressible, unless you expect transonic or supersonic flows. The standard N-S solver will be used, but with variable density like ideal gas. This will work to Mach 0.7 or so, and probable even higher if there are no shocks. What maximum Mach number do you expect?
This tutorial is a good starting point:
https://help.altair.com/hwcfdsolvers/acusolve/topics/tutorials/acu/acu_4400_intro_sl_r.htm
There might be too many unknowns in your system description. What is the physical real-world situation you are trying to model? Can you describe that in detail - including any images?
acupro
Re: How to use volumetric flow (m^3/s) - outlet boundary condition
Thank you for the response, Acupro. It seems quite helpful!
I will pen down my approach to the problem as of now:
1. I am using AcuSolve (HW CFD as pre-processor) and Mach No. is expected to be well below 0.7. Based on your recommendation, I will use the 'incompressible' option (that is what I assume you mean by the standard Navier Stokes solver?) with variable density.
2. The physical system is sort of a ventilation problem wherein an (air-)gas (toxic/flammable/harmful) mixture is being diluted by supplying fresh air and is being cleared out of the system via the outlet.
Therefore, the listed (in the original post):
Inlet 1 - represents the supply of fresh air from the fan (at a specific temperature and pressure)
Inlet 2 - represents the inlet of the toxic air-gas mixture (at a specific temperature and pressure)
Outlet - represents the diluted outlet to the environment (a certain level of dilution needs to be achieved before it is safe to release in the environment)
To start with a simple system (without baffles or moving parts to aid mixing/dilution), the schematics of the system is attached with two inlets at the bottom and one outlet at the top
Boundary conditions:
1. Volumetric flow rate at inlet 2 (fresh air) is available along with pressure and temperature data. I can either use this directly (m3/s) or convert it into mass flow rate (kg/s)
2. Volumetric flow rate at Outlet: is available along with the volume fraction of the gas (based on dilution needs). I am not sure if this flow rate can be used as an outlet boundary condition (any thoughts?). I am thinking of using pressure (atm) as the boundary constraint. I can try to convert it into the mass flow rate (kg/s) based on the combined density of the mixture (not sure if it is a homogenous mixture - assumption) and use it to compute the mass flow rate at inlet 2 (outlet - inlet 1)
3. Computed mass flow rate at Inlet 1
If you have any other example of gas transport or air-gas mixing in Acusolve or Simlab (pre-pro), it'll be helpful.
Thanks
I didn't see any attachment.
I think you'll have better success if you consider the two inlets as the knowns - using a standard outflow BC at the outlet. Then adjust the flow rate and concentration at inlet two (over various runs) to get your desired behavior at the outlet.
If you know the flow rate at inlet 1 and the flow rate at the outlet - that gives you the flow rate at inlet 2 - then you're just left with the concentration as the unknown at inlet 2, which you can vary over several runs to see what happens at the outlet.
acupro
Re: How to encrypt TCL Script?
Hello all,
I have used TCLPro setup to convert .tcl file to .tbc.
And it's working good in HM 2022.3
Yes, TclPro now is in https://sourceforge.net/projects/tclpro/
Re: Check symmetry
Hi Nancy,
To check symmetry, you can use the tool "Find Symmetry", below are images showing the steps to guide you along. It will be easier if you start initially by creating a node in the center of your surface as shown below:
Then, create a vector for your plane normal as shown:
Now, you can use the search tool to find "Find Symmetry" tool and follow the steps below:
The link below also explains how the tool works:
https://2023.help.altair.com/2023/hwdesktop/hwx/topics/pre_processing/geometry/symmetry_find_t.htm
Hope this helps!
Thanks,
TL Dorji
TL Dorji