Karakterisasi Distribusi Temperatur dan Unjuk Kerja Tangki Penyimpan Energi Termal Stratifikasi Bertingkat Dengan Variasi Debit Aliran

Abstract

A stratified thermal energy storage tank is often used on a cogeneration power plant to store thermal energy which is produced by exhausted gas energy utilizations from gas turbines. This tank is used as a thermal loads controller on that cogeneration power plant operation by charging the energy when the loads become minimum, and discharging when it is maximum. In this research, a new model is proposed by developing a mechanistic model which is determined from a non-linier regression function using analyzing of temperature distributions to determine the characteristic parameters of stratified PET tank. The temperature distribution data are reached from experiments ofvariable of flowrates.Applying a mechanistic model, the characteristic formulation of the tank is developed.Experiment results show that the temperature distribution of water in the stratified thermal energy storage tank can be represented by Four Parameter Sigmoid (FPS) equation. This equation generally connects the distribution temperature with four others parameters i.e. mean temperatures of cold water, mean temperatures of hot water, a centre point and also slope gradients of thermo-cline(S). Using the FPS equation, the temperature distribution parameters of the thermal energy storage tank are mathematically differentiated. Those parameters include a limit point, thermocline thicknesses, cumulative storage energy (Qcum), and characteristics of Half Figure of Merit (FoM1/2). The results show that values of S are influenced by the flowrates while the thermocline thickness, the cumulative energy storage (Qcum) and the ratio of Half Figure of Merit (FOM1/2) are influenced by the value of S.