Some aspects of thermal diffusivity for various soil layers in different harmonics

Abstract

Values of thermal diffusivity (K) in different soil layers for the first three harmonics have been computed for six stations in the dry farming tract of India by using amplitude ratio and phase lag. In general, the combined effect of all these harmonics gives the values of K close to the order of the experimental values. It is found that the theory of simple heat conduction is not applicable to soil medium. While the lowest values of K in all the harmonics are found at Rajahmundry, the highest values are observed at either Hissar or Bhubaneshwar for the first two harmonics and at Pantnagar for the third harmonic. Strong annual and bi-annual cycles dominate at Hissar. Pantnagar and Bhubaneshwar while quarterly cycle is significant only at Pantnagar.