gallery: clean up dilute riser description

        </header>

        <div class="row 50% uniform">

          <div class="8u 12u(small)">

            Circulating fluidized beds (CFBs) span a wide range of operating ranges throughout 

            their subsystems. The riser section is typically characterized by dilute transport. 

            Here, a 1.8 m section (~9M particles) of a pilot-scale CFB riser at 

            <a href="https://psri.org">PSRI</a> is modeled, just 1/10th of the physical 

            system's length. As high speed (15 m/s) gas flow drives the verically, denser than 

            average (1%) regions can form at (or migrate to) the wall and actually fall against 

            the mean flow. This phenomena can be observed on the right in the video while a 

            streamer climbes slowly on the left. We note that the domain is too small as the 

            streamer has interacted with its periodic image. Future work will simulate the full 

            18 m lenght of the riser. 

            Simulated by MFiX-Exa develop (git hash ef171c9d) using 24 GPUs on NETL's Joule2 HPC.

            Circulating fluidized beds (CFBs) span a wide range of operating conditions 

            throughout their subsystems. The riser section is typically characterized by 

            dilute transport. Here, a 1.8 m section (~9M particles) of a pilot-scale CFB 

            riser at <a href="https://psri.org">PSRI</a> is modeled, just 1/10th of the 

            physical system's length. As high speed (15 m/s) gas flow drives the 

            650 micron HDPE particles vertically, denser than average (1%) regions can 

            form at (or migrate to) the wall and fall against the mean flow. 

            This phenomena can be observed on the right in the video while a streamer 

            climbs slowly on the left. We note that the domain is too short, as the streamer 

            has interacted with its periodic image. Future work will simulate the full 18 m 

            length of the riser.

            Simulation by MFiX-Exa develop (git hash ef171c9d) using 24 GPUs on NETL's Joule2 HPC.

            The animation rendered with <a href="https://www.blender.org">Blender</a>.

            <p><p>