Effects of dynamic air flow in kitchen environments and the importance of air balancing


Author: Deebak Gobalraj –

GROWING HOSPITALITY INDUSTRY:

As we all know, the hospitality industry is developing a lot these days. Owners are investing heavily into their hotels in order to globalize them and create unique destinations. This development is mainly due to the increase in international tourism and business travel driving the need to create different cuisine options. The multitude of cuisine options and equipment designs can have a significant impact on dynamic air flows and energy consumption.

AIR CONDITIONING IN KITCHEN:

In the hospitality industry, the focus is being given to the improvement of centralized kitchen air conditioning to ensure that the chefs working in the midst of heat are safe and comfortable. Even small-scale kitchens are focused on providing air conditioned kitchens now more than ever.

VENTILATION SYSTEMS OF OLD AND MODERN KITCHEN TRENDS:

In the earlier days, importance was generally given to extract and discharge of exhaust air alone. Whereas now, in trending commercial kitchen ventilation system, the following ventilation systems are present to do air balancing and bring comfort in the kitchen zone-wise:

  • HOT Kitchen Zone – When cooking appliances are present, exhaust air and fresh air (makeup air) systems will be present to extract thermal plumes and radiant heat.
  • COLD Kitchen Zone – The preparation area and refrigeration area have conditioned air and return air systems present.
  • Dish Washing Zone – With the heavy output of steam, systems are in place to extract the steam immediately and recycle makeup air through the area.
DYNAMIC AIR FLOW AND IMPORTANCE OF AIR BALANCING:

Dynamic Air flow occurs due to the following reasons:

  • The heat load is not calculated per the equipment specifications.
  • Selection of improper kitchen equipment that leads to variation in heat load. Examples include wrong burner design, equipment without proper insulation, wrong electrical appliance selections.
  • High air draft transfer through doors/service door/high velocity diffusers
  • Equipment placement changes. An example would be changing the positions of equipment against the original kitchen design.
  • Extraction hood is undersized as it affects suction.
  • Increase in the number of people in the building.
  • Improper selection of exhaust fan, make up air fan, and exhaust & make up air ducting system

As a result of the air draft energy savings plummet!

ILLUSTRATION:

Something that I have observed quite often, is the high draft air transfer through different doors. This is a primary cause of dynamic air flow. Optimal kitchen design would allow the natural hot air from cooking to go undisturbed.

Service door opening affecting dynamic air flow.Service door opening allowing natural air flow.

In the 1st image above, the service door is open so the hot air that is rising is disturbed due to the high draft air from the next room, creating turbulence. The high draft should be balanced to decrease energy loss.

In the 2nd image above, the service door is closed allowing the hot air to rise without disturbance.

When there is a turbulence, the temperature in the kitchen will quickly rise as the extraction does not happen correctly and it combines with exhaust and supply air. Therefore, this makes the kitchen staff become very uncomfortable, air conditioning is increased to cool down the kitchen, and the exhaust is ramped up. Because of this, extra energy is used when it could have been avoided. If this is constantly being repeated, it will result in discomfort, hygiene will be affected, and there will be a huge loss of energy.

As you are designing your next kitchen, be cognizant of the fact that kitchen design impacts more than meets the eye. Kitchen efficiency goes beyond the layout that makes it easiest for your staff to work in, it entails energy usage and safety as well.

Authored By: Deebak Gobalraj

Deebak is the Market Development Manager for India - Southeast Asia for Melink Intelli-Hood.