Pressure drop and heat transfer properties for normal weight and lightweight pervious concrete

Abstract

This study examines the performance of pervious concrete when used for heating and cooling through forced air conditions. The influence of aggregate type, water-cement ratio, and paste volume on the air flow characteristics were examined through experimental evaluation of 10 mixes. The thermal properties and sensible heat energy stored in the pervious concrete were evaluated by measuring temperature changes with hot air flow. The results show that at a velocity of 0.35 m/s, the pressure drop falls within the range of 500 Pa/m to 8000 Pa/m. The pressure drop increases with an increase in the volume of paste to volume of aggregate ratio and decreases in water/cement ratio due to changes in the porosity and interconnected void structure of the pervious concrete. A modified pressure drop formulation based on the porosity, volume of paste to aggregate, and water/cement ratio is developed which provides a reasonable prediction for pervious concrete. The energy stored in the concrete can be accurately estimated based on the measured specific heat of the pervious concrete.