Investigating the use of alternative fuel pumps designs for cleaner aviation

近年来，随着对清洁航空的持续推动，人们一直在积极研究传统航空燃料的替代品。液氢是航空航天技术公司最近（2022年3月）的一份报告中确定的主要候选者之一。燃料泵传统上使用燃料润滑轴承，包括滑动轴承和滚动元件轴承。由于液氢温度极低、粘度低、密度低、容易导致轴承材料脆性以及可能存在的化学效应，这些轴承面临着非常特殊的挑战。本博士项目旨在研究适用于液氢泵的轴承的选择和工程设计。这种泵已经在火箭中使用了几十年，但火箭应用需要仅以分钟为单位的有效使用寿命。这项工作将探索传统轴承设计的定制和适用于燃油泵内服务的新型轴承设计的开发，这些轴承设计可以在所需的负载和转速下运行，同时还具有较长的使用寿命空间（> 10，000小时）。预计这项研究将包括传统的流体轴承设计（包括滑动轴颈轴承）以及（电）磁轴承，它也可能考虑利用可控的不平衡磁拉力在电机内，以协助管理轴承横向载荷。

With the continuing drive towards cleaner aviation in recent years, there have been active investigations into alternatives to traditional aviation fuel. Liquid hydrogen is one of the leading candidates as identified by a recent (March 2022) report from the Aerospace Technologies. Fuel pumps have traditionally used fuel-lubricated bearings including plain bearings and rolling-element bearings. These bearings face very specific challenges with liquid hydrogen due to the very low temperatures, low viscosity, low density, the tendency to cause brittleness of the bearing materials and the possible chemical effects that might exist. This PhD project sets out to investigate the selection and engineering design of bearings suitable for use in liquid hydrogen pumps. Such pumps have been used in rockets for decades but the rocket applications require an active service life measured only in minutes. This work will explore both the customisation of conventional bearing designs and the development of novel bearing designs suitable for service within a fuel pump that could operate at the required loads and rotational speeds whilst also having a long operational life spaces (>10,000 hours). It is expected that the study will embrace traditional fluid bearing designs (including plain journal bearings) as well as (electro- )magnetic bearings and it may also consider the possible exploitation of controllable unbalanced magnetic pull within an electrical machine to assist in managing bearing transverse loads.