Design and analysis of metal hydride reactor embedded with internal copper fins and external water cooling

Abstract

Summary Hydrogen is considered as a viable alternative fuel source for many domains. The main challenge in hydrogen technology is its storage. The most efficient form of storing hydrogen by volume is to adopt solid‐state storage. This is achieved by gas‐solid interaction using metal hydrides (MH). But, to achieve the full storing potential of MH, the heat management of the reactor is the critical factor. MHs having inferior thermal conductivity prove a challenge and thus, several kinds of research have gone into developing efficient MH reactors with features trying to enhance the heat transfer rate. In the view of this, in the present work, an MH reactor is designed and numerically (finite volume method) analyzed its heat transfer characteristics during hydrogenation and dehydrogenation of La0.9Ce0.1Ni5 at 293 K. Besides, to achieve improved heat transfer rates, new internal copper fins, and external water jackets are provided. The objective of the present work is to achieve high heat transfer rates with minimum reduction in MH mass within the reactor. Also, a parametric study is carried out to identify the optimized fin design by varying number fins, fin height, and fin thickness, which results in the optimum fin structure of 12 numbers, 12 mm, and 2 mm, respectively. The CFD simulation of MH reactor with and without fins results in improved heat transfer rates and reaction kinetics with internal copper fins. The maximum temperature rise during absorption is reduced by 22.3 K, and during desorption, the drop in bed temperature is reduced by 6.8 K, using optimized copper fins. The obtained results are compared with previous work and observed that the implementation of internal copper fins with external water cooling provides better heat transfer. The proposed reactor + fin arrangement can be efficiently used for the development of MH based thermodynamic devices.

Characterisation of La0.9Ce0.1Ni5 alloy for the development of single‐stage thermally driven sorption hydrogen compressor

“…The structure of the MH reactor used for performance prediction is shown in Figure 3. The details of design and analysis of the MH reactor including details of simulation (computational domain, mesh structure and boundary conditions) are given in the authors' recent article 56 . The required governing equations are solved using the second‐order upwind discretization scheme with the time step size of 0.1 seconds and meshing 2.4 million elements.…”

Performance comparison betweenH2‐metal hydrides andCO2‐adsorbents‐based sorption refrigeration systems

“…The initial condition of absorbing bed is F I G U R E 3 Reactor geometry 21 1 -Space for alloy powder, 2 -Reactor Cylinder, 3 -Coolant Jacket, 4 -Coolant Inlet, 5 -Coolant Outlet, 6 -Top Flange, 7 -Bottom Flange, 8 -Gas Inlet/Outlet, 9 -Thermocouples, 10 -Gas Distribution Tube All dimensions in mm ρ mat z, r,θ ð Þ= ρ i ; T mat z,r, θ ð Þ= T gas z, r, θ…”

“…Reactor geometry 21 1 – Space for alloy powder, 2 – Reactor Cylinder, 3 – Coolant Jacket, 4 – Coolant Inlet, 5 – Coolant Outlet, 6 – Top Flange, 7 – Bottom Flange, 8 – Gas Inlet/Outlet, 9 – Thermocouples, 10 – Gas Distribution Tube All dimensions in mm…”

Modeling and numerical simulation of an industrial scale metal hydride reactor based on CFD‐Taguchi combined method

“…The study of layouts on temperature distribution showed equal variation radially, but vertical layout showed significantly smaller variation in the longitudinal direction. Gupta et al 19 analyzed a reactor's performance through FVM using Ansys software with internal copper fins and an outer water jacket. A parametric study on the influence of fin geometry was carried, and the optimized configuration was with the fin with 12 mm height, 2 mm thickness, and 12 number of fins.…”