61786: Student Aerospace or Mechanical Engineering (f/m/x) - Concept development for the integration of liquid hydrogen tanks into an aircraft structure supported by analytical and numerical means

Updated: over 2 years ago
Location: Braunschweig, NIEDERSACHSEN
Deadline: The position may have been removed or expired!

In order to fulfill the ambitious goals in CO2 emission reduction new technical solutions are needed to break the global dependency on fossil fuels in the commercial aviation domain. One way to radically reduce C02 emissions would be the conversion of conventional propulsion systems to hydrogen-based ones. A fuel cell powering an electrically driven propeller as well as a hydrogen driven gas turbine are solution approaches currently investigated at several DLR sites. Both approaches require a safe integration of a robust hydrogen storage systems into the aircraft structure. This concerns in particular the challenge to store the hydrogen under liquified conditions (-253°C). Thus, the new aircraft’s structural components must be designed and sized in order to withstand the thermal loads implied by this severe temperature conditions on top of the mechanical loads induced by common flight and ground loads. In this context new design solutions are developed at the Institute of Composite Structures and Adaptive Systems.

This student vacancy offers you the chance to gain first hand work experience regarding the development of tanks for the storage of liquid hydrogen (LH2) designed for an aeronautical application.

Your student research paper, bachelor or master thesis will contribute to the research activities at DLR by focusing on the development and evaluation of different concepts for the integration of a LH2 Tank into an aircraft structure. The scope of your work will comprise an LH2 Tank which is not an integral part of the load bearing aircraft structure. This implies that flight and ground loads are carried by a conventional aircraft structure consisting of frames, longerons, stringers and skin. The tank itself is loaded by internal pressure loads and in case of a double walled vacuum insulated tank also by external pressure loads. In addition, the tank undertakes thermal loads resulting form the cryogenic condition of the stored hydrogen (-253°C). These thermal loads lead to substantial thermal contraction/expansion between refueled and un fueled condition.

Your task will be the concept development and preliminary sizing of the tank mountings which transfers the inertial loads from the tank to the aircraft structure. Tank mount fittings, on tank and on aircraft side, as well as necessary local reinforcements are within the scope of your thesis. Furthermore, the tank mountings must be designed to allow thermal expansion/contraction as well as imperfections resulting from manufacturing without inducing considerable bearing stresses.

Beside these mechanical challenges, tank mountings act as a thermal bridge dependent on the chosen design and lead to a short-circuiting of the tank insulation. Thus, the minimization of the thermal conductivity of the components must be kept in mind.

The following working steps are planed:

  • familiarize yourself with challenges linked to the integration of an LH2 tank into an aircraft structure
  • integrate into the surrounding research activities and derive requirements, boundary conditions and loads for the design and sizing of the tank mount
  • perform a literature research to keep up with the state of the art
  • list concepts from the literature and develop own concepts for the tank mounts as well as for the mount fittings on tank and aircraft side.
  • sssess the different concepts by means of thermal and mechanical performance
  • preliminary size selected concepts by analytical and numerical means

Your benefits:

At the Institute of Composite Structures and Adaptive Systems our students gain insights into a real research process for future aerospace components and contribute to new technical solutions with their own ideas. Our unique infrastructure offers you a working environment in which you have unparalleled scope to develop your creative ideas and accomplish your professional objectives. Our human resources policy places great value on a healthy family and work-life-balance as well as equal opportunities for persons of all genders (f/m/x). Individuals with disabilities will be given preferential consideration in the event their qualifications are equivalent to those of other candidates.