Numerical Analysis on Modelling Thermal Comfort Minor Operation Theatre

Abstract

An operation theatre (OT) is a special room inside the hospital where medical surgery is carried out by a surgeon with the help of medical personnel. Technical standards or requirements which have been set for heating, ventilation and air conditioning (HVAC) inside an operation theatre is important not only for the comfort of surgeon, patient, and medical personnel, but also to reduce the risk of surgical site infection during surgery. This research focus on Minor Operation Theatre (MOT) which is dental surgery room at Universiti Malaysia Perlis Health Centre with room dimensions of 2.89 m(H)×3.12 m(W)×3.4 m(L) is used for numerical analysis. The air flow supplied to the MOT is from single unit air-conditioning system. Computational Fluid Dynamics (CFD) analysis is a part of an investigation to determine the air flow and temperature distribution inside the MOT. A simulation conducted by using ANSYS Fluent only consider dry air inside MOT. Therefore, the main aim of this research is to compare and analyze the simulation of dry air conducted with previously obtained experimental data of humid air distribution inside the MOT. The comparison of humid and dry air temperature throughout the MOT shows that the difference is 25.3%. The average temperature of humid air inside the MOT is 21.8 °C while for dry air is 16.3 °C. Moreover, the cooling capacity of humid air and dry air are 2.23 kW and 1.64 kW respectively. Thus, the difference between humid air and dry air-cooling capacity is 26.5%. However, the dry air simulation and humid air simulation is the same if only the process is considered as simple cooling.

Investigating thermal environment inside the kitchen of air‐conditioned pantry car on Indian Railway using CFD

“…In this study, “CFD” simulations have been used to evaluate “air temperature” and “air velocity” distribution in the kitchen of an air‐conditioned “pantry car” (Sabtalistia et al, 2014; Yahya et al, 2019; Zainuddin et al, 2014). Further, thermal comfort was estimated in this analysis by identifying the thermal sensation range of occupants inside pantry car kitchens based on parametric studies.…”

“…A "finer meshing" was obtained at specific areas such as doors, airvents, exhaust hoods, heater using the "face-sizing" and "edge-sizing" mesh. In the present simulation, the total number of recorded elements and nodes were 138,920 and 756,022, respectively, found in the final mesh model, which is considered appropriate for CFD estimation (Yahya et al, 2019). Figure 5 illustrates the mesh model of an "air-conditioned railway pantry car kitchen.…”

“…In this study, "CFD" simulations have been used to evaluate "air temperature" and "air velocity" distribution in the kitchen of an air-conditioned "pantry car" (Sabtalistia et al, 2014;Yahya et al, 2019;Zainuddin et al, 2014). Further, thermal comfort was es- "ANSYS fluent R14.5 version software," the "CAD model (in igs file format)" of the pantry car has been imported.…”

“…Many investigators analyzed adequate thermal comfort in the kitchen environment by properly displacing the air supply system's state and validated the design modification using the “computational fluid dynamics (CFD)” simulation (Livchak et al, 2005; Qiu‐Wang & Zhen, 2006; Ren et al, 2012; Sabtalistia et al, 2014; Yuan et al, 2013). The CFD software was used in various countries to determine thermal comfort analysis such as; Anysys fluent 12.12 version in Indonesia (Sabtalistia et al, 2014), Fluent/Uns 5.3 in Malaysia (Zainuddin et al, 2014), AirPak 3.0 version in China (Li et al, 2014), ANSYS Fluent 12.0 version in Malaysia (Yahya et al, 2019), Airpak software 3.0 version in China (Yuan et al, 2013), ANSYS Fluent (CFD solver package) in Italy (Buratti et al, 2017), ANSYS fluent R14.5 version in India (Alam & Salve, 2021), CFX5 (version 5.5.1) in United Kingdom (Yang et al, 2006). In kitchen environment proper capture and containment efficiency could be achieved with an “airflow rate of 12,600 m 3 /h with an air supply temperature of 28°C” (Li et al, 2014).…”

Enhancement of Thermal Comfort Inside the Kitchen of Non-Airconditioned Railway Pantry Car

“…In particular tetrahedral volume, elements were used for the lattice of the CFD model. However, the patch conforming technique was included to develop the mesh with a "fine relevance center" [37]. Finer meshing at particular specific regions of importance like doors, air vents, exhaust, burner, fan using fine size meshing and face sizing meshing.…”