Dynamic Analysis of an Industrial Refrigeration System to Investigate Capacity Control

The paper is concerned with the development of a mathematical model which describes the behaviour of a quick freezing plant and its refrigeration system and its use in designing a capacity control system. The model is represented by sets of non-linear algebraic and differential equations which were derived using a ‘stirred tank’ approach on each section of the plant, in conjunction with conservation laws concerned with mass and energy balances, and with momentum equations relating force and flow rate. The capacity control system developed was based upon the measurement of initial and final product temperatures and product mass flow rate. This system showed an improvement in the operation of the plant over the existing control system. Problems of implementation are also discussed.