A newly harvested grain system (Stoecker 1971) has a high moisture content and must be dried to prevent spoilage. The drying can be achieved by blowing it with air. The seasonal operating cost in dollars per square meter of the grain bed for such a dryer consists of the cost of heating of the air.
where Q is air quantity delivered through the bed, m3 /m2 of bed area and Δt is the rise in temperature through heater in °C. The values of Q and Δt also influence the time required for adequate drying of the grain according to the equation
Using the geometric programming method, compute the minimum operating cost and optimum values of Q and Δt that will achieve adequate drying in 60 days.
