Simulation of Heat Exchange in Vessels with Helical Coils and Influence of Stirrer Position

Abstract

Agitated vessels are used for a wide range of applications, especially in chemical industry. This work is a pilot study on the influence of the stirrer installation height on the local as well as on the total heat flux with an immersed helical coil in an agitated vessel. A simplified geometrical model is used for observation of fundamental effects in contrast to a full mathematical model. The local heat flux, however, was observed to demonstrate the heat flux disparity along the coil. An optimum is proposed with the aim to maximize total heat flux and minimize tempering time.

Flow Fields in Stirred Vessels Depending on Different Internal Heat Exchangers and Vessel Bottoms

“… with the help of CFD simulations, but unfortunately only for their specific stirring system. Only a few current publications create the comprehensive, complete approach based on flow measurement and coupled flow simulation, e.g., , , , . It, thus, becomes clear that the substantial velocity fields measured within this study contribute to the combination and comparison of experimental and simulated data.…”

Optical Measurement Method of Particle Suspension in Stirred Vessels

“…For the evaluation and design of mixing and suspending processes, dimensionless parameters are used to describe the flow state, power input, quality of suspension and the behavior of the suspended particles , . While there are plenty of simulated CFD data available in literature for suspension reactors, practical measurement data for stirred vessels with internals are lacking.…”

“…For optimization purposes the following key parameters were identified – , , : minimal needed agitator frequency for different internals to ensure sufficient suspension quality, assessed by the 90 % suspension height criterion, resulting minimal motor power demand, velocity fields and flow conditions, turbulent kinetic energy and dissipation rate ε . …”