ECSS Final Report
Title: Investigating morphology evolution in thin-film polymer blends
PI: Baskar Ganapathysubramanian
PI Institution: Iowa State University
ECSS Consultant(s): Amit Chourasia (SDSC) and Christopher Thompson (Purdue)
Allocation Start/End dates: 4/1/2016 – 3/31/2017
Abstract:
We propose to deploy a highly parallel computational framework to efficiently model equilibrium
structures of flexible/semi-flexible polymers in complex, non-periodic geometries. The semi-flexible
(flexible) polymer physics is represented using the wormlike (Gaussian) chain model within the SelfConsistent Field Theory (SCFT) paradigm. The mathematical foundations and associated software
developments will enable modeling a wide range of systems of scientific and societal relevance, in
addition to the ability to investigate complex geometries with non-periodic boundaries in three
dimensions. Our emphasis is to create powerful, yet flexible software that can be utilized by a range of
users. To aid in making this accessible to as many users as possible, we intend to deploy a web-based
tool that will allow researchers without significant experience with high performance computing to
utilize this framework.
Executive Summary:
Short paragraph or two that summarizes the user problem, background information, concise analysis
and main conclusions/solutions.
Develop a gateway for the research team and collaborators to easily run simulation and visualization
through a web browser. The gateway will provide an ability to choose various parameters and
view/download data and results including visualizations. Ability to conduct interactive visualization of
results will also being explored.
Statement by the PI:
The collaborative team of staff from the Ganapathysubramanian group and ECSS staff have made some
very exciting preliminary progress in (a) designing a user friendly deployment framework for the SCFT
simulator, as well as (b) efficient visualization approaches to parse the produced high dimensional data. I
think the continuation of the ECSS project in this year will result in concrete approaches for both
deployment as well as visualization that would be very valuable.
Chronology:
Describe how the ECSS project was initiated (user submitted a proposal, a ticket, etc) and the steps used
to address the problem as the ECSS project was executed.
The project was initiated in conjunction with XRAC allocation request. The project developed a work
plan and is making progress.
Technical Details:
Describe the problem in technical terms along with possible solutions and the actual solution. Include
“before and after” performance charts etc. as applicable.
The project team initiated the project with a custom graphical tool that could submit job to their
university cluster. The goal was turn this project into a Science Gateway that will offer capabilities for
larger community to use the software developed by the project team.
The initial solution was developing the Science Gateway based on Hubzero/Diagrid platform. The actual
solution is still on intended lines. However slow development and unanticipated issues with HubZero
environment has impacted the project progress. These issues include installation and compilation of
appropriate libraries on HubZero environment, issue with X-Server and graphical interface, limitation on
directly using SSH libraries, etc. All these issues have been nearly resolved as of now. The allocation has
shifted from Stampede to Comet cluster, this change will require new submission setup for computation
and visualization. Visualization work was initially planned using Paraview software, but current
development is being undertaken via VisIt software. Once the Gateway pipeline is in place, the
visualization software could be switched.
Figure 1: Explore concurrent visualization of three scalar variables on a 2D grid data. Left image:
density_0 variable is shown via color, density_1 variable is represented by height deformation and
density_2 variable is shown by contour lines. Right image: The three variables are mapped using
monotonic color ramps going from white to red, green and blue and opacity ramp going from fully
transparent to fully opaque from minimum to maximum data range for each variable.
Collaboration details:
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Summarize the role and contributions (by name and institution) of the ECSS staff and project team
members.
1) ECSS Staff - Christopher Thompson @ 20-25 %, Amit Chourasia @ 20 -25%
a. Gateway development – Christopher Thompson (ECSS)
b. Visualization development – Amit Chourasia (ECSS)
2) Project Group – David Ackerman @ 20-25%, Alec Lofquist @ 20-25%
a. Visualization workflow assessment and integration; domain expert – David Ackerman (ISU)
b. Gateway integration assessment/testing – Alec Lofquist (ISU)
3) Technical Support – Steven Clark, HUBzero Admin
a. Consulting on technical expertise of sending jobs to XSEDE resources from HUBzero.
b. Aiding in minor changes to HUBzero middleware for supporting this project.
Outcome and Recommendations:
What was the final product/project produced by the team?
A gateway is under construction for the project.
What is the recommendation of the consultant for the PI to build upon this project in future?
A barebone setup is in place, but significant customizations are still needed. More time is needed to
accomplish the planned project goals. An extension was requested and granted for this work.
Lessons Learned:
Describe any lessons learned while completing this project that other ECSS staff (or XSEDE staff) may find
of value. Describe any plans to write an advanced topic article for documentation or to create a tutorial
based on lessons learned in this project. Consider volunteering to give a talk at the monthly ECSS
symposium.
Amit Chourasia gained familiarity with HubZero and also explored Multiple program multiple data
(MPMD) style execution of MPI codes.
Impact:
What impact does the completion of this project have on the project team, XSEDE and the community as
a whole?
The project team will gain a rich capability to provide their software to a larger community. XSEDE
resources will be used to deliver improved computation and visualization capability. The HubZero
platform will have another Science Gateway success story.
Publications:
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1) Diblock polymers under triangular confinement, J.H. green, D.Ackerman, B. Ganapathysubramanian,
to be submitted to Applied Physics Letters
2) "Effects of Confinement Geometry on Diblock Copolymer Systems Using Finite Element Analysis, J.H.
green, D.Ackerman, B. Ganapathysubramanian, presented at the National Conference on Undergraduate
Research, 2017 in Memphis
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