Experimental investigation of blended H2/CH4 combustion in combustors with block for micro-thermophotovoltaic

To extend the operation conditions and improve the working performance of micro-thermophotovoltaic system, the combustor with varied block setting and length is proposed, where blended CH4/H2 is employed. Effects of CH4 addition, burner dimensions and parameters on combustion characteristics, energy conversion and multi -factors on working performance are investigated under various flow rates. Results demonstrate that the con-sumption and production of OH and H radicals are strongly impacted by the CH4 blending ratio, affecting the flame regime, burning heat release and heat transfer in the combustion chamber. And 5-15 % CH4 addition is beneficial to the improvement of burner thermal performance, where the highest radiation temperature is achieved at mCH4 = 15 % in combustor C24-0.4 under lower fuel flow rate, while it is also affected by the burner setting. A higher CH4 mixing ratio contributes to the combustor with thin block and the thicker block with lower CH4 addition can both contribute to achieve a better working performance. Besides, the augment of burner length extends the operating conditions and the radiant area, while it reduces Tw, and combustor C29-0.6 obtains the highest radiation power of 48.1 W and electrical power output of 2.9 W with a system efficiency 2.2 % at mCH4 = 10 %, Vf = 635 mL/min and phi = 1.0. So, the appropriate CH4 addition, block setting and burner size can yield enhanced system performance.

Automated summary

This study investigates the effects of CH4 addition, burner dimensions and parameters on the working performance of micro-thermophotovoltaic systems. The results show that appropriate CH4 addition can enhance the thermal performance of the burner, and both thinner and thicker block settings have a positive impact on achieving better working performance. Additionally, increasing the burner length extends the operating conditions and radiant area.