Spatially resolved optical measurements of water partial pressure and temperature in a PEM fuel cell under dynamic operating conditions
نویسنده
چکیده
In situ non-intrusive measurements of water vapor partial pressure and temperature were performed simultaneously along two gas channels on he cathode side of a PEM fuel cell using tunable diode laser absorption spectroscopy. This measurement technique developed by us was utilized arlier to make measurements in a single bipolar plate channel of a prototype PEM fuel cell. The current study examines the variation of water partial ressure and temperature near the flow inlet and outlet during operation under both steady state and time-varying load conditions. For steady-state peration, an increase in the water vapor partial pressure was observed with increasing current density due to electrochemical production of water. s expected, the measurement channel near the inlet of the flow path showed a lower water vapor partial pressure than the outlet under identical oad conditions; however, the quantitative distribution of water content across the cell is important to understanding operational behavior of a EM fuel cell. These quantitative water concentration differences between two measurement channels are reported with variations in cell load and emperature. Temperature in the gas phase remained constant due to thermal equilibrium of the fuel cell. For time varying operation, no phase lag as observed between the load and the water vapor partial pressure. The outlet measurement channel showed higher partial pressure than the inlet ith larger differences for increasing cell load. The transient data matched the steady-state measurements at the same conditions. A temperature ise from the controlled value was observed at high current densities for the unsteady operation; thus, the temperature did not equilibrate on the ame time scale as the water partial pressure. 2006 Elsevier B.V. All rights reserved.
منابع مشابه
In situ simultaneous measurements of temperature and water partial pressure in a PEM fuel cell under steady state and dynamic cycling
In situ, line-of-sight measurements of water vapor partial pressure and temperature were performed in a gas channel on the cathode side of an perating PEM fuel cell. Tunable diode laser absorption spectroscopy was employed for these measurements for which water transitions sensitive o temperature and partial pressure were utilized. The previously demonstrated methodology for water partial press...
متن کاملIn Situ Optical Diagnostics for Measurements of Water Vapor Partial Pressure in a PEM Fuel Cell
A fiber optic coupled diode laser sensor has been constructed for in situ measurements of water vapor partial pressure in active proton-exchange membrane (PEM) fuel cell systems. The bipolar plate of a prototypical PEM fuel cell was modified to allow for transmission of a near infrared laser beam through the flow channels on either the fuel or oxidizer side of its membrane-electrode assembly. T...
متن کاملEnergy Management Simulation in a PEM Fuel Cell System
In this research the simulation of an air independent Proton Exchange Membrane Fuel Cell (PEMFC) propulsion system was taken into consideration. The system consists of several parts including PEM fuel cell stack, metal hydride and liquid oxygen (LOX) tanks, and also pre-heaters of oxygen and hydrogen gases along with other heat exchangers, to ensure proper operation of system. The heat recovery...
متن کاملExperimental Study of Oxidant Effect on Lifetime of PEM Fuel Cell
In recent decades, fuel cells have been widely used in energy generation. In a PEMFC, considering the specific application, two types of oxidants are used. Durability tests, which are highly costly products, are of crucial importance in evaluating the lifetime of fuel cells. The purpose of the present paper is to investigate the performance of a fuel cell by changing the type of oxidant from a...
متن کاملInvestigation of vessels pressure effect on PEM electrolyzer performance by using a new OneDimensional Dynamic Model
In recent years energy shortage and environmental impacts due to consuming fossil fuels have led to developing renewable energy sources systems. Since these sources are not reliable and are usually time dependent, an energy storing system like hydrogen production is required. In this regard, PEM electrolyzer can be efficiently used to decompose liquid water into hydrogen and oxygen. Because of ...
متن کامل