Research on low-temperature performance of plate-fin hydrogen preheater for a proton-exchange membrane fuel cell

ABSTRACT

In order to improve the cold-start performance of the fuel cell vehicles, a rapid anode heating system is provided to enable the stack to quickly reach its optimal performance at low temperatures. In this study, a three-dimensional element model of plate-fin heat exchanger has been developed and used to study the effect of structural parameters of staggered fins on the hydrogen transport phenomena and heat transfer performance. A series of simulations were carried out to study the influence of different fin parameters on heat transfer performance. Good agreement is found by comparing the simulation values with the predicted values of the experimental correlation and the deviation is less than 10%. It is shown that fin length has the greatest impact on the thermal performance factor of the radiator, while the contribution of fin thickness is minimal. Experiments show that the maximum heat transfer capacity of the plate-fin heat exchanger reaches 900 W, and the performance of the stack is increased by about 15%. Through the sensitivity analysis of the structural parameters of the hydrogen preheater, the optimal parameter combination was obtained. This research provides guidance for the design of the preheater and plays an important role in improving the low-temperature durability of hydrogen fuel cell engines.

KEYWORDS:

• Proton-exchange membrane fuel cell
• hydrogen preheating
• staggered fin
• heat transfer
• Taguchi evaluation algorithm

Nomenclature

h Fin height (mm)

p Stagger pitch (mm)

l Stagger length (mm)

L Total fin length (mm)

D₁ Minimum inside diameter (mm)

D₂ Maximum inside diameter (mm)

$\mathrm{\Delta }p$ Wall thickness (mm)

T_c Core thickness (mm)

Ac Minimum free flow area (m²)

D_h Hydraulic diameter (mm)

$\mathrm{\Delta }p$ Entrance and exit loss coefficient

$\mathrm{\Delta }p$ Kinematic viscosity of the fluid

$\mathrm{\Delta }p$ Nusser number

Pr Prandtl number

j Heat transfer factor

f Friction factor

h Convection heat transfer coefficient

m Mass flow rate (kg/sec)

$\mathrm{\Delta }p$ Pressure drop (pa)

P Heat transfer power (W)

t₁ Inlet temperature (°C)

t₂ Outlet temperature (°C)

L Tube length (cm)

T Temperature (°C)

A Air-side surface area (m²)

σ Minimum flow-to-face area ratio

Dimensionless groups

Re Reynolds number

Exp Experimental

Sim Simulation

C Coolant

H Hydrogen

us Unreinforced surface

Greek symbols

ρ Density (kg/m³)

λ Thermal conductivity (W/m·k)

C_p Specific heat at constant pressure (j/kg·k).

Additional information

Funding

The authors would like to thank the reviewers for their helpful suggestions. This work is supported by the National Natural Science Foundation of China (52075481), Zhejiang Provincial Natural Science Foundation (LR19E050002, LQ21E060009), Zhejiang Province Key Science and Technology Project (2019C01057), Talent introduction start-up fund project (20200724Z0095). --> -->