MODELING THE DISTRIBUTION OF ISOPROPYL N-(3-CHLOROPHENYL) CARBAMATE [CIPC] IN BOX POTATO STORES

A numerical model has been produced to predict the distribution of dep osits of the sprout suppressant isopropyl N-(3-chlorophenyl) carbamate [CIPC] in box potato stores. The model considers the movements of the CIPC by forced convection, sedimentation, natural convection and diff usion. Measurements have mostly shown high levels of CIPC on the top o f the uppermost box, with levels decreasing towards the floor of the s tore. The model predicts this pattern and indicates that particle size , the temperature difference between the air inside and around the box es, and the application rate of the chemical have a large effect on th e levels and uniformity of CIPC deposits. Smaller particles (2 mu m) c an lead to better uniformity of distribution, but they are prone to na tural convection effects which are difficult to control and they are s low to deposit which could lead to greater losses from the store.