<div dir="ltr"><div dir="ltr"><div>Dear Mats, Joe,</div><div><br></div><div>The complexity depends on what kind of coupling terms you want to take into account. Energy and density source/sink terms are easiest (I did those in JOREK), and there are also ways to write a pressure coupling.</div><div>You can see <a href="https://pubs.aip.org/aip/pfb/article-abstract/4/7/2033/940129/Three-dimensional-hybrid-gyrokinetic">https://pubs.aip.org/aip/pfb/article-abstract/4/7/2033/940129/Three-dimensional-hybrid-gyrokinetic</a> for the pressure coupling scheme.</div><div>This has been applied in JOREK at <a href="https://pure.tue.nl/ws/portalfiles/portal/242595133/5.0119435.pdf">https://pure.tue.nl/ws/portalfiles/portal/242595133/5.0119435.pdf</a> (see chapter 4 of <a href="https://pure.tue.nl/ws/files/174874567/20210705_Dvornova_0207.pdf">https://pure.tue.nl/ws/files/174874567/20210705_Dvornova_0207.pdf</a> for more detail).</div><div>Of course this has been written for a very specific formulation of the MHD equations, but I hope the ideas therein may help you.</div><div><br></div><div>All the best,</div><div>Daan</div></div><br><div class="gmail_quote gmail_quote_container"><div dir="ltr" class="gmail_attr">On Thu, 24 Apr 2025 at 09:54, 王美乔 <<a href="mailto:2521795240@qq.com">2521795240@qq.com</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div><p>Dear Dr. Holmstrom,</p>
<p>Thank you so much for your kind reply — I’m really glad to hear from you!</p>
<p>As you mentioned, coupling fluid and Hybrid-PIC in a self-consistent way is indeed quite challenging. We’ve found that handling the collision effects between particles and the background fluid, as well as advancing the electromagnetic fields properly, are among the most difficult aspects. We’re currently exploring possible approaches to address these issues, and we look forward to further discussions and exchanges with you.</p><p>
</p><p>Thanks again for developing the Hybrid-PIC solver in FLASH！！</p>
<p>Best regards,<br>
Joe<br>
University of Chinese Academy of Sciences (UCAS)</p></div><div><br></div><div><hr align="left" style="margin:0px 0px 10px;border-width:0px 0px 1px;border-style:none none solid;border-color:currentcolor currentcolor rgb(228,229,230);height:0px;line-height:0;font-size:0px;padding:20px 0px 0px;width:50px"><div style="font-size:14px;font-family:Verdana;color:rgb(0,0,0)"><a id="m_-6451440812647339016in_alias" style="white-space:normal;display:inline-block;text-decoration:none;font-family:-apple-system,BlinkMacSystemFont,PingFang SC,Microsoft YaHei" href="https://wx.mail.qq.com/home/index?t=readmail_businesscard_midpage&nocheck=true&name=%E7%8E%8B%E7%BE%8E%E4%B9%94&icon=http%3A%2F%2Fthirdqq.qlogo.cn%2Fg%3Fb%3Dsdk%26k%3DibcvtYgppl5lYjlauGM0CmQ%26s%3D100%26t%3D1648049135%3Frand%3D1648443710&mail=2521795240%40qq.com&code=" target="_blank"><table style="white-space:normal;table-layout:fixed;padding-right:20px" cellpadding="0" cellspacing="0"><tbody><tr valign="top"><td style="width:40px;min-width:40px;padding-top:10px"><div style="width:38px;height:38px;border:1px solid rgb(255,255,255);border-radius:50%;margin:0px;vertical-align:top"><img src="http://thirdqq.qlogo.cn/g?b=sdk&k=ibcvtYgppl5lYjlauGM0CmQ&s=100&t=1648049135?rand=1648443710" style="width: 100%; border-radius: 50%;"></div></td><td style="padding:10px 0px 8px 10px"><div style="font-size:14px;color:rgb(51,49,46);line-height:20px;padding-bottom:2px;margin:0px;font-weight:500">王美乔</div><div style="font-size:12px;color:rgb(153,152,150);line-height:18px;margin:0px">2521795240@qq.com</div></td></tr></tbody></table></a></div></div><div> </div><div><div><br></div><div><br></div><div style="font-size:12px;font-family:Arial Narrow;padding:2px 0px">------------------ 原始邮件 ------------------</div><div style="font-size:12px;background:rgb(239,239,239);padding:8px"><div><b>发件人:</b> "Mats Holmstrom" <<a href="mailto:matsh@irf.se" target="_blank">matsh@irf.se</a>>;</div><div><b>发送时间:</b> 2025年4月24日(星期四) 下午2:35</div><div><b>收件人:</b> "flash-users"<<a href="mailto:flash-users@flash.rochester.edu" target="_blank">flash-users@flash.rochester.edu</a>>;</div><div></div><div><b>主题:</b> Re: [FLASH-USERS] Hybird-PIC in FLASH</div></div><div><br></div><br>Hello Joe,<br> I wrote the hybrid PIC solver in FLASH.<br><br>I am not aware of any works that couples fluid and particles, in FLASH, <br>or any other MHD solver.<br><br>What usually is done is to take the MHD E and B fields and simulate test <br>particles, but that does not give any coupling between fluid and particles.<br><br>An interesting idea, but not trivial to derive the math, algorithm and <br>then implement it<br><br>Regards,<br>Mats Holmstrom<br>Swedish Institute of Space Physics<br><br><br>On 2025-04-23 18:31, 王美乔 wrote:<br>> Dear FLASH Team,<br>> <br>> I hope this message finds you well.<br>> <br>> I am currently using FLASH for some Hybrid-PIC research. I have noticed <br>> that modeling all plasma components as particles is extremely <br>> computationally expensive. To address this, I am attempting to treat <br>> most of the low-energy plasma as a fluid, while representing the <br>> high-energy portion as particles.<br>> <br>> However, I have encountered several difficulties with this approach. I <br>> would like to ask whether anyone on the team has experience with such a <br>> setup. Specifically, is it possible to simulate both fluid and <br>> Hybrid-PIC particles simultaneously in FLASH and allow them to interact <br>> with or drive each other? If so, are there recommended methods, modules, <br>> or example cases you could share?<br>> <br>> Thank you very much for your help and advice!<br>> <br>> <br>> Best regards,<br>> Joe<br>> University of Chinese Academy of Sciences<br>> <br>> <br>> _______________________________________________<br>> flash-users mailing list<br>> <a href="mailto:flash-users@flash.rochester.edu" target="_blank">flash-users@flash.rochester.edu</a><br>> <br>> For list info, including unsubscribe:<br>> <a href="https://flash.rochester.edu/mailman/listinfo/flash-users" target="_blank">https://flash.rochester.edu/mailman/listinfo/flash-users</a><br>_______________________________________________<br>flash-users mailing list<br><a href="mailto:flash-users@flash.rochester.edu" target="_blank">flash-users@flash.rochester.edu</a><br><br>For list info, including unsubscribe:<br><a href="https://flash.rochester.edu/mailman/listinfo/flash-users" target="_blank">https://flash.rochester.edu/mailman/listinfo/flash-users</a><br></div>_______________________________________________<br>
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