Thanks to everyone for concerning about this question, after two days trial and error, I have made some progress, but there is still something haunting me, and two new questions arose, details are written as follows:
For table expression problem:
I also considered to increase rows of table to reach the goal previously, however, it is very time-consuming and unsmart, since this method is actually realized by interpolation, thus, we need to select points(as much as possible) to reflect pressure variation, in this case, in order to get points enough to describe the pressure of one circular in certain R(R1 <= R <= R2), where R1=10.15mm, R2=11.75mm, for example, when R = 10.15mm, corresponding pressure P = 20e+6 Pa, I selected 360 points to assign corresponding pressure value, besides, in order to reflect pressure variation according to R, in R direction, I also need to select enough points, here, I selected 60 points, i.e. the increment of R is 0.05mm, as a result, 1 R --- 360 points, now we have 60 different R values, we need 60*360=21600 points, which is too much! So, this method is not suitable for me.
In Figure 6, I selected 360 pressure points for one circular(i.e. 1 point for 1 degree), and 5 different R values which are 10.15mm, 10.5mm, 11mm, 11.5mm, 11.75mm, as we can see from it, pressure effect is successfully displayed.
For function expression and unit problem
Now, I have to resort to method 2, i.e. ‘Function method’ as I had shown in Figure 9, the pressure function is P=k*ln(0.0175/R),(in this case, R is described by ‘m’), where k=1.37e+8, however, according to the pressure contour, the result of load is not what I expected, corresponding pressure arrows are shown in Figure 10. After I tried several times, I found it was caused by unit, the unit I intended to adopt is m-Pa-N-s, so, when I set property of material, the density is 8600kg/m^3(typical copper density) shown in Figure 13(a), and the Young’s modulus 1.1e+11 Pa and Poisson’s ratio 0.34 in Figure 13(b), when came to prescribe load, either in ‘table expression’ or ‘function expression’, R must be input in ‘mm’(Figure), if it was in ‘m’, the result would be wrong, for example, in Figure 6, 7, 8(Table expression method whose corresponding table is shown in Figure 14) as well as Figure 11 and 12(Function expression method), the unit of R is ‘mm’, and once the unit of R was converted to ‘m’, the load result would be displayed as what is presented in Figure 10(Function expression method) and Figure 16(Table expression method), why did this happen? What is the reason?
Another two new question
(4) How to increase the number of load arrows?
As is shown in Figure 11, by using ‘Function expression’, arrows of load is very scarce compared to those in ‘Table expression’, is there any method to increase the number of arrows?
(5) How to view load in contour mode in load module?
Is it possible to display the load prescribed by ‘Function expression’ in contour form like Figure 2, or at least the same as ‘Table expression-plot data source’ shown in Figure 7?
Regards,
Lee
Updated Figures
Figure 5
Figure 6
Figure 7
Figure 8
Figure 9
Figure 10
Figure 11
Figure 12
Figure 13(a)
Figure 13(b)
Figure 13
Figure 14
Figure 15
Figure 16
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Hello everyone, I encountered a problem when I was trying to exert pressure load on circular surface in ABAQUS, here are the details:
I wanted to exert a pressure load which varies with radius on a circular surface shown in Figure 1.
Figure 2 is the expected effect which is realized in Workbench in which I used a tabular form to describe the relation ship between Pressure and X(which is radius R) in cylindrical coordinate system, however, in ABAQUS, the table has four parameters to fill in, actually, in my opinion, every row in the table defines a pressure value in one point, which is not what I wish to get.
There is an other way called ‘Expression field’ shown in Figure 4 to set load, in this method, we can edit an function to realize the goal, however, I failed and I don’t know why.
Thus, I have several questions, they are:
(1) How to exert a pressure load which varies with radius R? just like Figure 2
(2) Why I failed to get the expected load effect by using ‘Expression field’ method?
(3) It is about unit problem, in ABAQUS, the unit has to be consistent, what is this mean? Does it mean unit should be in the same system throughout whole simulation, or it just in one setting? For example, if I use ‘Pa’ to describe the value of pressure when I define materials, in this section(defining material), I need to use ‘m’ to describe length, however, when comes to another section, such as defining load, do I have to use ‘m’ and ‘Pa’ in table when I tried to set the load by tabular method, or I can use ‘mm’ and ‘MPa’ instead when I fill in the table?
Regards
Lee
Figure 1
Figure 2
Figure 3
Figure 4
