3. Introduction
Ventilation systems in hospitals should provide an air flow that maintains the optimum temperature, humidity and
health of the personal and patients.
Hospital air needs to change as much as possible for removing of microorganisms and particles, for this “Special
hygienic ventilation systems “should be used.
4. What we are going to do?
- Acıbadem Hospital wants to make a new operating room in Erzurum or Diyarbakır. We are going to select which city is more
efficiency for selected ventilation system.
5. - It is defined as the ratio of the partial water vapor pressure in the air at the same temperature to the partial pressure of
the water vapor in saturated form and is calculated by the following equation.
- Firstly, we take the relative humidity (Bağıl Nem) values of our cities
Relative Humidity
Diyarbakır: In January % 75 Erzurum: In January %78
In September %35 In September %54
Taken from TS 825
[TS 825 is a “Thermal insulation requirements for buildings” standards for Turkey]
6. Internal and External temperature values
Diyarbakır:
- Dry bulb temperature for cooling: 39.7 Celsius
- Wet bulb temperature for cooling: 22.3 Celsius
- Dry bulb temperature for heating: -8.7 Celsius
- Dew point temperature: 14.03
- Altitude: 675m
Erzurum:
- Dry bulb temperature for cooling: 29.5 Celsius
- Wet bulb temperature for cooling: 18 Celsius
- Dry bulb temperature for heating: -26.2 Celsius
- Dew point temperature: 11.85
- Altitude 1900m
7. Operating Room
Standards
- In operating rooms temperature should be 20-23 ° C, relative humidity should be 30-60%. Positive pressure should be
provided in operating rooms and to the corridors and other adjacent areas. Ventilation systems in operating rooms should
provide air filtration of 90% or more.
- Conventional operating room ventilation systems should have at least 15 filtered air changes per hour and at least 3
(20%) of them should be clean air.
8. Acıbadem Project
Acıbadem Operating Room
Because of we are making an Operating room to Acıbadem Hospitals. Their standards for operating rooms are:
- In operating rooms temperature should be 20° C
- In operating rooms relative humidity should be %40
- 34 filtered air changes per hour
Acıbadem wants 30 m² operating room. We designed that as (6m x 5m). Height of the operating room is 4m.
We use the main standard and give the air from the top and exiting from bottom. We also add exiting air to the top
for supporting.
We will use “Reference System (No Heat Recovery)” system design for operating room.
A constant volume system with 100% outside air supply and 100% exhaust is the reference system against
which the rest are compared.
9.
10. Calculations
- We took all the data we need from Acıbadem and Standards. Now we are going to make the calculations to find which city is
more efficient.
Operating Room Air Flow
Firstly, we find our Operating Rooms air flow:
Room Volume x Air Changes per hour = Air Flow
(6m x 5m x 4m) x 34 = 4080 m3/h
11. Acıbadem Air Conditioning System Design
This figure is design of our air conditioning system.
- Our duct dimensions are 0.5m x 0.5m.
- Air flow rate in the duct is 5 m/s
12. Filters and Pressure Loss
In the OR’s standards there are 3 different type of filter. We stick to the standard and took the filters data from MGT Air Filters
Company.
1) In the first step, filter is G-4 type of filter
- Our air flow rate is 4080 m3/h, so we need two filter with 2800m3/h.
- Its pressure loss is 75pa.
2) In the second we need sensitive filter called F9 type of filter
- We need two filter with 2000 m3/h, Its pressure loss is 150 pa.
13. 3) At the end we use HEPA Filter. HEPA filters are the best in Operating Rooms
So, in addition total pressure loss is the system;
- 505 Pa in the filters
- 150 Pa in the heat pump system Total is 1055 Pa
- 400 Pa in the duct system
We need two filter with 2550m3/h, its pressure loss is 280pa
14. Acıbadem Operating Room Enthalpy
Acıbadem standards for OR is;
- %40 Relative humidity
- 20 Celsius OR temperature
From psychrometric chart;
- Operating room’s enthalpy is 34.88 kj/kg
15. Diyarbakır January Enthalpy
- Relative humidity in January is %75
- Outside max temperature is -8.7 Celsius
- Diyarbakır January enthalpy is -5.39kj/kg
16. Diyarbakır September Enthalpy
- Relative humidity in September is %35
- Outside max temperature is 39.7 Celsius
- Diyarbakır September enthalpy is 81.29 kj/kg
17. Erzurum January Enthalpy
- Relative humidity in January is %78
- Outside max temperature is -26.2 Celsius
- Erzurum January enthalpy is -25.69kj/kg
18. Erzurum September Enthalpy
- Relative humidity in September is %54
- Outside max temperature is -29.5 Celsius
Erzurum September enthalpy is 65.53kj/kg
19. Finding Heating Loads
In psychrometric chart there are 4 type of Air conditioning
process. We will use only Cooling and dehumidifying type of
from psychrometric chart.
From this moment we use an application called Airmap to show you changes of humidity and temperatures on the
psychrometric chart.
When we calculate the heating load, we need these data:
- Indoor Temperature (Always constant 20 Celsius)
- Indoor Humidity (Always constant %40)
- Outside Temperature
- Outside Humidity
- Total air flow ( Always constant 4080 m3/hr)
20. Heating Load at Diyarbakır In January
Heating Load (QL) is 35.644 kW
Cooling Load at Diyarbakır In September
Cooling Load (Qc) is 72.9 kW
21.
22.
23. Heating Load at Erzurum In January
Heating Load (QL) is 58.564 kW
Cooling Load at Erzurum In September
Cooling Load (Qc) is 55.215 kW
24.
25.
26. Heat Pump System in Diyarbakır
From the psychrometric chart;
- Heating Load is 35.6 kW, For -8.7 Celsius
- Cooling Load is 72.9 kW, For 39.7 Celsius
Our project needs a Heat Pump system that greater than 73kW. We use Frigo Block Heat Pump System Company for our project.
- We find two different model of Heat Pump for Diyarbakır project
27. We select the Frost series central units with 3 compressors.
Because its more efficiency and cheaper than the other.
28. Heat Pump System in Erzurum
From the psychrometric chart;
- Heating Load is 58.564 kW, For -26.2 Celsius
- Cooling Load is 55.215 kW, For 29.5 Celsius
Our project needs a Heat Pump system that greater than 59kW. We use Frigo Block Heat Pump System Company for our
project.
We find two different model of Heat Pump for Erzurum project
29. We select the Frost series central units with 2 compressors.
Because its more efficiency and cheaper than the other.
30.
31. To sum up, Acıbadem Hospital wants to make a new operating room in East side of Turkey. They gave us 2 cities in east
Diyarbakır and Erzurum. Acıbadem will build one Operating room which city is cheaper and more energy saving. We find some
values and make calculations to find which city is more suitable.
From our calculations, Erzurum is cheaper building cost and more energy saving than Diyarbakır. At the Erzurum project
Acıbadem needs to buy an Air Conditioning system with 2 compressors but in the Diyarbakır, Acıbadem needs to buy an Air
Conditioning system with 3 compressors because of the heating loads.
For selected air conditioning systems;
- In Erzurum 97800-Watt energy usage
- In Diyarbakır 126600-Watt Energy usage
From these reasons, Acıbadem Hospital will make a new operating room in Erzurum.
Conclusion
