Energy and mass transport in porous icy and dusty media. Microphysical simulations and applications to comets

多孔冰和尘埃介质中的能量和质量传输。

• 批准号: 285787948
• 负责人: Dr. Yuri Skorov
• 金额: --
• 依托单位: Institut für Geophysik und Extraterrestrische Physik
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2016
• 资助国家: 德国
• 起止时间: 2015-12-31 至 2019-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/285787948?language=en
• 关键词: Energy; mass; transport; porous; icy

This proposal will investigate in detail the physical processes in the porous sub-surface layers of small Solar System bodies. This project stems from results of several space missions to comets and results of our laboratory experiments elucidating the transport processes inside porous dusty and icy media under the physical conditions matching those observed at the surfaces of comets. In this project we will develop a novel modular computer model of transport of energy and mass in porous dust-ice surface layers. Our model will consist of i) an entirely new microphysical description of granular samples, both homogeneous and heterogeneous, ii) new multidimensional self-consistent treatments of the transient mass and energy transfer in such varied media, based on discrete and continuum approaches, and iii) a new microphysical model of the evolution of the dust-ice porous mixture. The results of recent and forthcoming laboratory experiments will be used to develop and verify novel computer models. The strength of our approach lies in the (i) use of innovative complementary approaches to computer simulations, from microscopic to mesoscopic scale, and (ii) close relationship of theoretical and experimental works, which will significantly enhance the reliability and applicability of the computer models. As a result, we will get powerful theoretical tools that will allow us to investigate a wide range of problems concerning transient exchange processes in the sub-surface regions of comets. We intend to model the physical processes leading to the observed high temperature of the nucleus surface and its extremely low thermal inertia, the persistent release of volatiles as well as of non-volatiles, the particle ejection process from the cometary surface and its evolution into the inner cometary coma. With the arrival of the European Space Agency's Rosetta spacecraft at the comet 67P/Churyumov-Gerasimenko, unique scientific data from 21 experiments are becoming available. These will, for the first time, allow a detailed study of a comet in sufficient resolution to investigate the fundamental open questions in cometary physics. The key central question to be addressed is how cometary activity works and what drives it. Based on many years experience in the field, we believe that the project will deliver prominent results.

该计划将详细研究太阳系小天体多孔次表层的物理过程。该项目源于对彗星的几次空间飞行任务的结果和我们的实验室实验结果，这些实验阐明了在与彗星表面观察到的物理条件相匹配的物理条件下多孔尘埃和冰介质内部的传输过程。在这个项目中，我们将开发一个新的模块化的计算机模型的能量和质量的传输在多孔尘冰表面层。我们的模型将包括i）一个全新的微观物理描述的颗粒样品，均质和非均质，ii）新的多维自洽处理的瞬态质量和能量转移在这样的不同介质中，基于离散和连续的方法，和iii）一个新的微观物理模型的演变的尘冰多孔混合物。最近和即将进行的实验室实验的结果将用于开发和验证新的计算机模型。我们的方法的优势在于（i）使用创新的互补方法来进行计算机模拟，从微观到介观尺度，以及（ii）理论和实验工作的密切关系，这将显着提高计算机模型的可靠性和适用性。因此，我们将获得强大的理论工具，使我们能够调查广泛的问题，在彗星的次表面区域的瞬态交换过程。我们打算模拟的物理过程，导致观察到的高温的核表面和极低的热惯性，挥发物以及非挥发物的持续释放，从彗星表面的粒子喷射过程及其演变成内部彗星彗发。随着欧洲航天局的罗塞塔号航天器抵达67 P/丘留莫夫-格拉西缅科彗星，从21项实验中获得的独特科学数据正在变得可用。这将是第一次允许对彗星进行足够分辨率的详细研究，以调查彗星物理学中的基本开放问题。要解决的关键核心问题是彗星活动是如何运作的，是什么驱动了它。基于多年的实地经验，我们相信该项目将取得显著的成果。