On the single-zone modeling for optimal climate control of a real-sized livestock stable system

Abstract

This paper discusses mathematical modeling for development and implementation of a model-based optimal indoor climate control for a real-sized livestock stable system. As a typical modern and large-sized stable system, the considered stable uses hybrid ventilation and low-pressure climate control strategies. Due to the main concern of the feasibility for commercializing the developed control system, the single-zone concept is adopted for modeling the considered system. Based on the energy balance and mass balance analysis, the thermal and flow dynamics of the indoor climate are quantitatively described. The models for air inlets, outlets and their driving systems as well as the heating systems, one is used to heat up the stable and another one is used to emulate the animals' heat generation, are also extensively studied. The system parameters are identified through arranged experiments. The developed model is further validated through comparison with real system's operations. Even though some deviations in terms of the indoor temperature can be observed, the developed model shows consistent intendancy with the real system. Nevertheless, some modeling errors can be compensated by an optimal (constraint MPC) controller developed based on this simple model. The obtained results show a clear feasibility to use a simple single-zone model for developing a sophisticated optimal control to handle largesized climate control problem.

Control of variable-speed pressurization fan for an offshore HVAC system

“…where C w is a specific pressure coefficient related to wind direction [13], H out is the equivalent height of the outlet center to the reference pressure level and H npl is the natural pressure level [14].…”

“…How to effectively reduce buildings' energy consumption and make the operation more environmentally friendly is very crucial for human beings to cope with the climate change and global housewarming. In recent decades, very extensive studies have been focused, from development of efficient buildings [4], [7], mathematical modeling of indoor climate [1], [3], [5], to optimal control of buildings ventilation/Heating Ventilation and Air-Condition (HVAC) systems [8], [13]. Nevertheless, it has been noticed that almost all existing studies only focus on the on-shore situations.…”

Optimal control of offshore indoor climate

“…A recent study shows that the energy consumption of buildings accounts up to 40% of energy used worldwide, and buildings lead to 21% of all greenhouse gas emissions [10]. In recent decades, there has been extensive studies on the development of efficient buildings [4], [7], mathematical modeling of indoor climate [1], [3], [5], and optimal control of buildings' ventilation/HVAC systems [8], [12], [13], [14] etc. The literature survey reveals that almost all existing studies on energy-efficient buildings focus on the on-ground situations.…”

“…this is very important for offshore systems, from a safety perspective; and • The MPC technique originally rooted and grew up in industrial process applications. Furthermore, some existing investigations [12], [13] for on-ground indoor climate control have indicated that there is a huge potential for using the MPC technique for efficient indoor climate control. It would be quite interesting to check how to extend these results/methods to handle offshore indoor climate situations.…”

“…It would be quite interesting to check how to extend these results/methods to handle offshore indoor climate situations. After a mathematical model for a typical offshore indoor climate and its HVAC system is derived using the Single-Zone concept [1], [13], a constraint MPC controller is developed and afterwards compared with a PID solution derived from the existing HVAC control system. Our simulation results clearly show that the MPC performance is much better than the PID's, in terms of faster time responses, less overshoots and more robustness to disturbance.…”