Seyed Mojtaba Hosseinnia

Université de Sherbrooke | UdeS · Faculty of Engineering

Performance of available air-source heat pumps (ASHP) for buildings is extremely influenced by the outdoor air temperature (OAT). When OAT falls below –20°C, especially in subarctic climate, most commercially available ASHPs lose their defined functionality. To address this issue, a novel cascade heat pump (CHP) is proposed that utilizes two natura...

Decarbonizing industrial heating globally is a significant challenge, driving the integration of high-temperature heat pumps for heat recovery and electrification in the industrial sector. However, current high-temperature heat pumps with low global warming potential refrigerants face limitations in delivering high-temperature heat due to their res...

High temperature cascade heat pump with two separate refrigerants is a crucial system for decarbonizing industrial heating through electrification. The selection of optimal working refrigerants and temperature lifts relies on not only the thermodynamic analysis outputs such as coefficient of performance but also economic and environmental analyses....

High temperature cascade heat pumps (HTCHP) with water, aka R718, at the high stage (HS) and ammonia, aka R717, at the low stage (LS) exhibit a great potential to satisfy both industrial heating and cooling demands while mitigating the global warming issue via industrial decarbonation/electrification as both refrigerants have extremely low global w...

Water has been used as a natural, extremely low global warming potential refrigerant in high-temperature heat pumps. The steam compressor's extra high discharge temperature at high-pressure ratios (e.g., 15) can be prevented via liquid water injection during the compression process as an effective desuperheating method. The proposed thermodynamic a...

Two-step approach for optimum solar assisted ground source heat pump integration in buildings is proposed. At the first step energy targeting based on dynamic pinch analysis allows to target the energy and optimum equipment size according to buildings’ dynamic demands, and as a result, several energy efficient daily design candidates are extracted....

Application of solar assisted ground source heat pumps (SAGSHP) in buildings have been increased in recent years. However, a systematic approach for integrating the optimum SAGSHP system in buildings in order to meet the space heating/cooling and the domestic hot water loads is still missing. A novel dynamic targeting approach is proposed. It can p...

Heat integration techniques such as pinch analysis can play a significant role in saving energy in the design of buildings. The application of pinch analysis in this sector encounters difficulties due to the highly time-dependent behavior of energy streams such as waste heat and solar thermal collectors, as well as the possible need for heat storag...

Vertical ground heat exchangers (GHE), as part of a ground source heat pump system, have been utilized for energy extraction/injection from/to the ground, i.e. a renewable source of energy, in the heating/cooling months to reduce building energy utilization. The current available GHE sizing methods are mostly based on several over-simplified one or...

Thermocline thickness (TLT) is the best parameter to quantify the thermal performance of stratified thermal energy storage (TES) tanks as it defines the inactive part of a storage medium. A detailed literature review reveals that there is no consensus in the community on the temperature band where the TLT is quantified. In this study, a new criteri...

In this study, dynamic streams including space heating, domestic hot water, renewable solar thermal energy and waste heat such as gray water are extracted from a typical multi-family building under extreme winter conditions for one day or 24 h. The maximum heat recovery (MHR) is targeted through an adapted time slice model (TSM) of pinch analysis....

Vapor absorption in aqueous LiBr inside a vertical tube absorber is studied numerically. The governing equations of concentration and energy have been derived in general forms, including the species interdiffusion, Soret and Dufour effects due to combined concentration and temperature gradients during absorption process. All thermophysical properti...

The rate of absorbed water vapor over a horizontal tube bank in a water-cooled falling film absorber depends on several parameters and working conditions. The flow regime between the tubes in falling film absorbers is one of the most influential parameters in the amount of the absorbed vapor. Among different falling film regimes, in this study, the...

Vapor absorption inside free-falling drops of 4.4 mm in diameter in an adiabatic absorber is studied numerically. The full process of forming drops including sessile stage, turning to pendant shape, detachment and free-fall are investigated. In this simulation, the full Navier–Stokes equations are solved. The volume of fluid (VOF) method is used to...

Conjugate mixed convection-conduction heat transfer from a circular cylinder submerged in power-law fluid has been investigated numerically. The steady two-dimensional conduction equation for the heating cylinder and steady two-dimensional laminar boundary layer equations for the flowing fluid are solved simultaneously using finite difference schem...

The purpose of this study is to investigate the effects of different internal designs of traditional wind towers on their thermal behavior numerically. Among the enormous variety of designs of internal partitions in traditional wind towers, which are used in hot and dry areas of Iran, five main important types were chosen. Calculations were done us...

A new design of Wind Tower is investigated numerically under different structural parameters and environmental conditions. The new design is some wetted columns, consisting of wetted curtains hung in the tower column, which are modeled as surfaces that inject droplets of water with very low speed. The CFD open source package – Open FOAM – is used....