Dynamics of gas flow between interconnected vessels: Experiments and simulations

Abstract

The emergency relief systems of pressure vessels often direct their discharge to containment vessels known as catch tanks or dump tanks, which are part of effluent handling systems. Although many models exists for vent sizing and critical flow calculation, there is less information about the impact of depressurization on the catch tank. This work addresses this topic by presenting experimental and simulation studies. We report experimental temperatures and pressures in the pressurized vessel and in the catch tank during the depressurization of air or helium from several initial conditions. A reproducibility study demonstrates the excellent agreement among the results of different experimental runs. On simulation, we present results of the depressurization of a vessel connected to a catch tank. To accomplish this, an existing dynamic simulator is extended by including a one-dimensional transient heat transfer model and by enabling the simulation of interconnected vessels. The experimental and calculated pressure profiles are generally in very good agreement. The agreement of the experimental and calculated temperature profiles is good but the calculated profiles tend to overestimate the temperature variations in each vessel during the depressurization process compared to the experimental data.