Confronted with low-quality heat source

such as high ash contents

discontinuity and instability in waste heat recovery

innovations are required in the structure of typical heat transfer surface. In this paper a novel structure with rhombus heat transfer surface was presented. This heat transfer surface was efficient in both waste heat recovery and ash blowing. In the heat transfer process

the new heat transfer surface showed similar performance with the staggered tubes arrangement

for instance enhanced heat transfer and relatively large fluid flow resistance and higher convection heat transfer coefficient in the shell side. In the dust blowing process

this surface performed like the aligned tubes arrangement

which was easy to clean and efficient in dust blowing. Numerical simulation and experimental investigation were conducted to obtain heat transfer and flow performance of the new structure. Both numerical and experimental results indicated that the new structure met basic requirements of waste heat recovery

achieving highly efficient heat transfer along with convenience of dust cleaning and descaling.