'Air-conditioning simulation of an office space' simulation project by Milad_Mafi

#1

I created a new simulation project called 'Air-conditioning simulation of an office space':

This project shows how to simulate the airflow inside an office space.


More of my public projects can be found here.

#2

Description

In the recent spate of urbanization, there has been a rapid increase in the overall energy consumption along with a stark rise in the number of pollutants added to the atmosphere by industries as well as individuals.
 
Air-conditioning, a major culprit in global warming, is one of the prime causes for urban energy consumption. In the current day, offices, homes, and restaurants have installed large capacities of air conditioning to increase thermal comfort. It is up to HVAC engineers to increase the energy efficiency of the system. This may be done by studying the airflow pattern in a room/office space with an air conditioner.

Project Goals

Using the SimScale platform, we will simulate the airflow in an office space with an air conditioner. Based on the results of the aerodynamic analysis, we may draw conclusions to in order to achieve a similar output for a smaller energy consumption.

Analysing certain parameters, suggestions can be made regarding the most effective positions for the A/C vent and exhaust in addition to modifications in the room design.

Geometry

Our CAD engineers have concocted a 3D model of a typical workspace, suitable for performing a simulation. The bottom right of the room has been assigned as the vent (inlet) and the top left has been assigned to be the exhaust (outlet). This geometry is uploaded as a .STEP file onto the SimScale platform.
 

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Overall Geometry of considered office space
 

Meshes

A hex-dominant mesh is created and mapped onto the geometry. Apart from the inlet and outlet, the rest of the geometry is apportioned as ‘wall’. A safe assumption is taken here: The various materials in the office interact with the air in the same manner.

 

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Enclosure of the office space under study
 
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Internal view of meshed office space

Simulations

An analysis type of Fluid Dynamics - Convective Heat Transfer is chosen along with a Laminar turbulence model and a Steady-State Flow. All walls are assigned a similar material (custom) stemming from the assumption mentioned above.

The initial temperature of the room is set to be 20°C and the pressure is equal to atmospheric pressure (105 Pa). The inlet is defined as a velocity inlet with an airflow velocity of 0.75 m/s and a temperature of 10°C. Whereas, the outlet is defined as a pressure outlet with a pressure value of 105 Pa.

Results and Conclusions

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Velocity streamlines of airflow
 
The image above shows a streamlined visualization of the velocity field where the different colours represent the absolute velocity of air. The image below depicts a temperature contour plot indicating the warmer and cooler portions of the office space.
 
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Temperature contour plot
 
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Temperature varaitation along a 45° slice
 
From the results, we noticed that the cooler temperatures remain at the bottom and the warmer ones remain at the top. Moreover, different parts of the room are at a different temperature and there is no uniform distribution. To ensure better mixing (and hence, convection), a configuration consisting both the inlet and outlet to be on top but on opposite sides of the room should be employed.
 
This conclusion may be validated by the elementary principle - Hot air rises and cold air sinks. Therefore, by having the vent at a higher level of the room will facilitate better distribution of temperature across the entire office space.

#3

i need help on designing and analysing a clean room.

#4

Hi sgenda, try to ask a more detailed question on the forum. I’m sure somebody will reply shortly: www.simscale.com/forum

#5

how you make the bolean geometry? some especific program?

#6

Hi sir, i need your help in modelling an agricultural building concerning heat transfers in it

#7

Hi @ptolentino!

You can post your problem along with a link to your model (if you have one) in the project support section of this forum. Either the PowerUsers, me or some other users will help you out then!

Best,

Jousef

#8

Hi, why these contours are not labeled? What's the range for the velocity or temperature?

#9

Hi @mamali14,

you are right that legends are missing in this case. Why don’t you perform post-processing by yourself and see in what range the corresponding quantities are? :slight_smile:

Best,

Jousef