r********o
发帖数: 1423 | 1 I am interested in this topic. Anyone can help to recommend a good entry-
level book on this area?
Thanks | s********r
发帖数: 257 | 2 FEA of composite is based on laminate theory. So usually we use shell to
model the fiber reinforced composite panel.
There are many failure criterion for composite:
Tsai-Wu,Tsai-Hill..., Hasin's 3D criterion (Recommend)is comprehensive,
including:
1. Fiber tension failure
2. Fiber compressive failure
3. Matrix tensile failure
4. Matrix compressive failure
5. Delamination
You can go through "Analysis and performance of fiber composite" for entry
lever, or you can go "Failure Criteria in Fiber rei | r********o
发帖数: 1423 | 3 Thanks. But what I am really interested in is the damage tolerance analysis.
It's the scenario of some damage (crack, delamination, disbond, core shear
buckle, dent) has been created to the laminate, and then what type of
analysis can help to predict the crack growth, further delamination or
disbond. Your suggestion is for analysis that "to prove the damage will not
occur"
【在 s********r 的大作中提到】
: FEA of composite is based on laminate theory. So usually we use shell to
: model the fiber reinforced composite panel.
: There are many failure criterion for composite:
: Tsai-Wu,Tsai-Hill..., Hasin's 3D criterion (Recommend)is comprehensive,
: including:
: 1. Fiber tension failure
: 2. Fiber compressive failure
: 3. Matrix tensile failure
: 4. Matrix compressive failure
: 5. Delamination
| s********r
发帖数: 257 | 4 About the damage tolerance, I did some composite struction analysis before.
I decrease the modulus of the element to a very small value when the damage
occur at that element. For instance, when matrix fails, I take E2=0, G23=0.
If fiber breaks, E1=0, G12=0, G13=0....
As I know, it seems your interest is on the micro scale analysis of the
composite (not macro :-) ), Crack analysis of composite is very complicated.
Take cross-ply composite for example, the crack may happens in the
longitudinal-ply
【在 r********o 的大作中提到】
: Thanks. But what I am really interested in is the damage tolerance analysis.
: It's the scenario of some damage (crack, delamination, disbond, core shear
: buckle, dent) has been created to the laminate, and then what type of
: analysis can help to predict the crack growth, further delamination or
: disbond. Your suggestion is for analysis that "to prove the damage will not
: occur"
| r********o
发帖数: 1423 | 5 呵呵,俺想学习的就是后者啊
FAA新规定，对复合材料的弱项，damage tolerance的应用，必须对所有飞机做damage
tolerance的强度校核。简单说就是，如果机身上一块sandiwich panel有crack/delam/
disbond了，FAA要知道飞机局部/总体在这种condition下，外载荷不变接着飞能撑多久。
这是一个新的requirement。有心的可以多留意，一旦入了这行优势无穷哦，呵呵
.
damage
.
complicated.
delamination
【在 s********r 的大作中提到】
: About the damage tolerance, I did some composite struction analysis before.
: I decrease the modulus of the element to a very small value when the damage
: occur at that element. For instance, when matrix fails, I take E2=0, G23=0.
: If fiber breaks, E1=0, G12=0, G13=0....
: As I know, it seems your interest is on the micro scale analysis of the
: composite (not macro :-) ), Crack analysis of composite is very complicated.
: Take cross-ply composite for example, the crack may happens in the
: longitudinal-ply
| f*****s
发帖数: 3868 | 6 益个头, 没绿卡都是扯淡
我老板是这方面的绝对大牛,
我6年phd就做这个了
外国学生找工作斗难得很
我找了一年才找到了别的行业的
damage
delam/
久。
【在 r********o 的大作中提到】
: 呵呵,俺想学习的就是后者啊
: FAA新规定，对复合材料的弱项，damage tolerance的应用，必须对所有飞机做damage
: tolerance的强度校核。简单说就是，如果机身上一块sandiwich panel有crack/delam/
: disbond了，FAA要知道飞机局部/总体在这种condition下，外载荷不变接着飞能撑多久。
: 这是一个新的requirement。有心的可以多留意，一旦入了这行优势无穷哦，呵呵
:
: .
: damage
: .
: complicated.
| r********o
发帖数: 1423 | 7 you will get GC eventually.
Do you have any recommendations on related books/publications?
【在 f*****s 的大作中提到】
: 益个头, 没绿卡都是扯淡
: 我老板是这方面的绝对大牛,
: 我6年phd就做这个了
: 外国学生找工作斗难得很
: 我找了一年才找到了别的行业的
:
: damage
: delam/
: 久。
| f*****s
发帖数: 3868 | 8 等我熬到绿卡, 多了几年非航空工业的经验
再想回去就难了
不过也无所谓, 我现在这份工也还可以
只是可惜了我当年航空的梦想, 呵呵
【在 r********o 的大作中提到】
: you will get GC eventually.
: Do you have any recommendations on related books/publications?
| r********o
发帖数: 1423 | 9 good for you...but you still don't answer my questions yet...
【在 f*****s 的大作中提到】
: 等我熬到绿卡, 多了几年非航空工业的经验
: 再想回去就难了
: 不过也无所谓, 我现在这份工也还可以
: 只是可惜了我当年航空的梦想, 呵呵
| m****n
发帖数: 293 | 10 Please google "Continuum Damage Mechanics", I think this will help you find
a solution. I have a lot of papers in the field at hand. Please let me
know if you need them.
damage
delam/
久。
【在 r********o 的大作中提到】
: 呵呵,俺想学习的就是后者啊
: FAA新规定，对复合材料的弱项，damage tolerance的应用，必须对所有飞机做damage
: tolerance的强度校核。简单说就是，如果机身上一块sandiwich panel有crack/delam/
: disbond了，FAA要知道飞机局部/总体在这种condition下，外载荷不变接着飞能撑多久。
: 这是一个新的requirement。有心的可以多留意，一旦入了这行优势无穷哦，呵呵
:
: .
: damage
: .
: complicated.
| m****n
发帖数: 293 | 11 And I have developed a computational package based on abaqus to predict the
life of composite strucutres with damages under a variety of loads (cyclic,
impact and dynamic) after analyzing the detailed distributions and histories
of displacement, strain and stress as well as energy release rate around
crack and delamination. Do you think if this tool can be used for damage
tolerance? Thanks. | l***o
发帖数: 7937 | 12 Does this package assume crack develops in a predetermined direction, as
is often the case for the debonding, decohesion or delamination of laminates, using CZM and cohesive models, or is it moderately general like the crack-tip element in NASTRAN and ANSYS, or even more general like FRAC3D?
What is the output of the package? Is it given as the history of crack size, or is it given as the history of damage index as in CDM, or is it given as the number of cycles as many fatigue software packages
【在 m****n 的大作中提到】
: And I have developed a computational package based on abaqus to predict the
: life of composite strucutres with damages under a variety of loads (cyclic,
: impact and dynamic) after analyzing the detailed distributions and histories
: of displacement, strain and stress as well as energy release rate around
: crack and delamination. Do you think if this tool can be used for damage
: tolerance? Thanks.
| c****w
发帖数: 565 | 13 once a model with damage, under loading condition, then it will crack in the
way you want, such as you want fatigue or creep model. The constitutive
material model has already handled your problem. I don't understand why you
need damage tolerance.
About crack growth, damage size increase, delamination area, it all depends
how to define them in your model. Say damage parameter (0-1) for crack
growth, you can visualize it in any CAE software after running simulation.
About composite structure, I a | h***e
发帖数: 79 | 14 国内有本杨光松的书《复合材料损伤力学》，可以看看。这方面文章也很多，但做基础
研究的多。
美国的航天是难进呀，现在在苦苦地找。 |
|
