[gmx-users] water flow

[Alex]

Okay, that's a reassuring start. I guess I will just have to try and 
track the cumulative flux to see if it's constant. I wouldn't want the 
flux to be increasing throughout simulation. Never used this option, 
obviously, so thanks for the tip!

Alex


On 6/12/2018 11:38 AM, Justin Lemkul wrote:
>
>
> On 6/12/18 1:37 PM, Alex wrote:
>> Hi Justin,
>>
>> Looking at acc-grps text in the manual, it's a bit unclear how a 
>> constant flow rate would be achieved in this case. Is a constant 
>> force in the amount of molecule mass, times the acceleration vector 
>> applied to each molecule in the group, or is there actual 
>> acceleration magically maintained?
>>
>
> I'm not familiar with the code, but it's what I know people have used 
> to impose a constant force on a bulk solvent without having to use the 
> pull code (which will throw errors).
>
> -Justin
>
>> Thanks,
>>
>> Alex
>>
>>
>> On 6/12/2018 8:24 AM, Justin Lemkul wrote:
>>>
>>>
>>> On 6/11/18 7:38 PM, Alex wrote:
>>>> Hi all,
>>>>
>>>> I'm trying to explore pressure-induced processes, i.e. externally 
>>>> induced
>>>> water flow across a porous membrane that spans the entire box in 
>>>> XY. There
>>>> are obvious choices:
>>>>
>>>> 1. Introduce the same type of a membrane without pores and make it 
>>>> a piston
>>>> with pull code, e.g. constant force or tiny constant velocity along Z.
>>>> 2. Apply constant force pull directly to the entire solvent group.
>>>>
>>>> Any other ideas on osmosis-like processes? Has anyone tried any of the
>>>> options above?
>>>
>>> I would think the pull code would be more headache than it's worth 
>>> in this case. I'd simply try inducing the flow with acc-grps.
>>>
>>> -Justin
>>>
>>
>