A Determination of Thermal Diffusivity of Dairy Manure through One-dimensional Fourier Solution



High moisture levels in fresh dairy manure provide a suitable environment for growth of pathogens and cause environmental pollution. Dry manure can be used for different purposes in agriculture and in livestock industry. Such heat properties of manure as specific heat, thermal conductivity and thermal diffusivity are important needed factors for the design and development of a suitable efficient dryer. In this research the thermal diffusivity of dairy manure was determined through one-dimensional Fourier solution. Experiments were carried out at 20, 40, 60 and 82% (w.b) moisture contents and at 40, 50, 60 and 70°C temperature levels. Thermal diffusivities of the dairy manure were obtained in a range of from 0.904×10-7 to 2.11×10-7 m2/s. The trend of increase in thermal diffusivity with by increase in temperature was of a linear type. At a certain constant temperature, thermal diffusivity increased by increase in moisture content (from 20% to 40% (w.b.)) while decreasing at contents above 40% (w.b). A polynomial model can adequately estimate the thermal diffusivity coefficient, ?, (agreeable with moisture content vs. temperature of dairy manure), with a coefficient of determination of 0.99.