Rational analysis of mass, momentum, and heat transfer phenomena in liquid storage tanks under realistic operating conditions: 1. Basic formulation

• Published in: Solar energy 1992-08, Vol.49 (2), p.87-94
• Main Authors: Parrini, F., Vitale, S., Alabiso, M., Castellano, L.
• Format: Article
• Language: English
• Subjects: 142000 - Solar Energy- Heat Storage- (1980-); 990200 - Mathematics & Computers; Applied sciences; computer aided analysis; COMPUTERIZED SIMULATION; Computers; CONTAINERS; Energy; ENERGY LOSSES; ENERGY TRANSFER; Exact sciences and technology; FRICTION; GENERAL AND MISCELLANEOUS//MATHEMATICS, COMPUTING, AND INFORMATION SCIENCE; HEAT PUMPS; HEAT TRANSFER; LOSSES; MASS TRANSFER; MOMENTUM TRANSFER; Natural energy; PHYSICAL PROPERTIES; SIMULATION; SOLAR ENERGY; Solar energy storage; SPACE HVAC SYSTEMS; Storage; TANKS; tanks (storage); THERMAL DIFFUSIVITY; THERMAL ENERGY STORAGE EQUIPMENT; THERMODYNAMIC PROPERTIES; VISCOSITY
• ISSN: 0038-092X; 1471-1257
• DOI: 10.1016/0038-092X(92)90142-W

This paper presents a computer code that analyses the performance of storage tanks using water as the working fluid. The new aspects of our work include the following items: (a) the transient Navier-Stokes equations are expressed in two-dimensional Cartesian and cylindrical coordinates, under the assumption of the Boussinesq approximation, (b) the effective viscosity and thermal diffusivity are evaluated by using a simplified form of the Deardorff turbulence model, (c) the energy equation is solved over a domain which includes the tank and a large portion of the surrounding soil, (d) some properly defined source terms have been introduced in the governing equations to describe inlet/outlet devices inside the tank, and localized friction losses, and (e) the boundary conditions are time-dependent to correctly describe the daily heat exchanges between tank, solar collectors and heat pumps for space conditioning. The DF technique and an improved formulation of the MAC method are used to solve the conservation equations. Comparisons with literature studies indicate discrepancies between 0.02 and 0.5%. The results of several tests simulating realistic operating conditions will be shown in the second part of the paper [29].