The aim of ventilation for commercial kitchens is capturing fumes and odours, providing fire protection measures and insuring comfort. But the technologies concerning extraction and introduction of fresh air are not numerous.In this article, the author explains how difficult are the dimensioning of the equipment and the calculation of the airflow to extract.The author also refers to guide and regulations related to commercial kitchens.
The second part of the paper deals with the measurements of the indoor thermal environment and the ventilation performance of a commercial kitchen.Measurements were made with a tracer gas (SF6) which is non-toxic and odorless.A smoke machine (ROSCO) was placed on the floor of the middle of the kitchen while operating the ventilated ceiling system. Air inlets near the floor or at the lower parts of the walls brought fresh air in the lower part of the kitchen and pushed the smoke upward.The results almost agreed with the results of the previous numerical simulation ( in part 1).
The impact on thermal comfort of the way of introducing replacement air (to replace air being exhausted by the hood) in a kitchen was analysed using mathematical models and laboratory experiments with a tyhermal mannequin. Results allow to rank systems for replacement air introduction from the most to the least tolerable : displacement ventilation, mixing ventilation with ceiling air diffusers, front-face discharge and backdrop plenum.
This study was aimed to analyse the ventilation efficiency and indoor air quality in the conventional kitchens, when porous screens were installed on the transoms. Numerical simulations and laboratory full-scale experiments were carried out in the model kitchen in the Department of Architecture at National Cheng-Kung University. The influences of porous screens on the temperature fields, flow structures and ventilation rates were indicated. The "Tracer-gas Concentration Decay" method was conducted to measure the air exchange rate and the age of air in the model kitchen.
Samples near a frying pan, grill plate or deep fryer were taken in 10 kitchens in order to determine the composition of aerosol and vapours in the surrouding air. The main components are aerosols and low molecular aldehydes. Up to 90% of the aerosols consist of triglycerides and fatty acids. An aerosol concentration of 1.5 to 2 mg/m3 can be used as a guideline value to design the ventilation system.
The complex design, build, maintain and retrofit process has been mapped in order to provide a logical structure and flow for the kitchen design system. The developed prototype kitchen design concept demonstrates the capabilities and requirements of a truly integrated and efficient design process. The design of the professional kitchen environment follows the methodology of the industrial design process. The kitchen layout design and time dependent internal loads are specified through the understanding of a specific restaurant and its food service process.
In 1998, a program was initiated to develop an innovative backshelf hood system that could achieve a much lower capture and containment (C&C) exhaust rate than traditional backshelf hoods. As part of this effort, an evaluation of the state-of-the-art tools in use in commercial kitchen ventilation in the United States was undertaken. This paper presents the new hood concept KVL, a description of the latest techniques available for determining C&C performance, and comparisons of the KVL new hood concept to other hoods.