Required Thermal Comfort Conditions Inside Hospital Operating Rooms (Ors): A Numerical Assessment

Abstract

This paper presents a computational model along with a thermal comfort criterion aimed at assisting the design of operating rooms (ORs) from the perspective of meeting suitable flow patterns and thermal comfort conditions for the occupants. The computational model is based on the finite volume method (FVM) to describe the air inside ORs along with the human thermoregulation model implemented in virtual mannequins for thermal comfort. The air model considers turbulent fluid motion, species transport and the conservation of energy, including thermal radiation. The human thermoregulation model incorporates two interacting systems of thermoregulation. Namely, the passive system and the active system. The comfort criterion is based on the effective temperature of body parts which is a more suitable indicator than the commonly utilized predicted mean vote (PMV) and predicted percentage of dissatisfied (PPD) for body segments. The focus of the study is placed on the influence that the inlet thermal conditions provided by the air conditioning (AC) system have on the flow pattern and thermal comfort of the occupants. The results show that, for the selected conditions, lower air inlet temperatures than previously reported are required to operate at satisfactory comfort standards. It was also observed that smaller inlet temperatures bring about several improvements in the flow pattern inside the OR such as the size reduction of several recirculation zones (RZs). Nonetheless, smaller inlet temperatures bring about some drawbacks such as the size reduction of the ultra-clean ventilation (UCV) zone and the need of extra air-cooling power.

Recent Achievements in Research on Thermal Comfort and Ventilation in the Aspect of Providing People with Appropriate Conditions in Different Types of Buildings—Semi-Systematic Review

“…Parameters in the operating room: predicted mean vote (PMV) and predicted percentage of dissatisfied (PPD) were investigated by means of CFD simulation in [64]. The influence of air inlet temperature on the flow pattern and thus on the thermal comfort sensation was investigated.…”

“…Research on hospitals is conducted for various spaces in hospitals: hospital ward [57,61], emergency room [59], operation room [59,60,62,64], intensive care unit [59], or nursing home [63]. It would be expected that healthcare facilities should have controlled ventilation through which a better indoor environment can be achieved, and this is indeed the case.…”

“…Natural ventilation/controlled ventilation/both types of ventilation were present in correspondingly 29%/57%/14% of the reviewed papers. Most studies use controlled ventilation [59][60][61][62]64]. There are various research methods: simulations [57,60,62,64], in situ measurements [57,59,61,62], surveys [57,[61][62][63], and their various combinations.…”

“…Most studies use controlled ventilation [59][60][61][62]64]. There are various research methods: simulations [57,60,62,64], in situ measurements [57,59,61,62], surveys [57,[61][62][63], and their various combinations. The main limitations are the inability to generalize the results due to the test conditions in only one climate [59,61,63] or the limited number of analyzed systems [60,64].…”