Phase change material slurry (PCS) can serve as cold storage material and secondary refrigerant to transport cold energy with the advantages of good flow ability and high energy density. Ice slurry is a safe and efficient cold storage medium

which has been widely used in cold storage air conditioning. However

the low temperature of ice slurry preparation limits its efficiency in terms of energy utilization in air-conditioning systems. The urea slurry can be prepared by cooling the high mass concentration urea solution

and the phase change temperature range covers the air-conditioning condition. Furthermore

the phase change latent heat is high

and thus the urea slurry can be potentially used in several applications. In this paper

the thermos-physical properties of urea solution and the fluidity of urea slurry are experimentally studied. The results indicated that the phase transition temperature of urea solution with a mass concentration of 43%–48% is 5–12 ℃

and the latent heat is in the range of 213.7–223.2 J/g. Furthermore

the density of urea solution (mass concentration was higher than 32.5%) at the liquids increased with solution mass concentration

while the tendency of kinematic viscosity was opposite. Additionally

the flow characteristics of urea slurry were affected by the solid fraction and Re; thus

it can be regarded as a dilatant fluid under different working conditions.