ACREX - 2013

Watch the video ACREX - 2013 on YouTube

I was in the ACREX-2013 exhibition held at Bombay Exhibition Center on 7th,8th & 9th in Mumbai. Watch the video above to get a feel.

Rules of Thumb in Refrigeration Engineering

The rules of thumb article below is a part in series of lecturers of Prithvi Datta (UK) ] he used at

Colleges of HE & FE in United Kingdom with practical experimentation for promoting innovation and

modification in R&HVAC Engineering.Thousands of Trainers of Trainees and students of courses from

Apprentice Mechanic to Ph.D. had appreciated the series to master skills for Experimental Studies

and Techniques.

Part 1

During my professional duties as Lecturer in R&AC in a Humberside college of HE&FE we

were using R12,22 or 502 for following use of Rule of Thumbs. I tried to use R410A for the

following example using limited data available to me at that moment.Selected R410 for this

application with COP of 8.33 is good example.

why some refrigerant cannot be used without waste of energy and operational and capital

losses.Phase & State of Refrigerant at important specific points within as simple

Refrigeration Cycle working in UK with R410A working at ambient temp. 25 deg for

refrigeration duty of - 20 deg. C (ignoring pressure drop caused within the pipework).

Refrigeration Cycle should be studied at 12 specific point in the cycle

with R410A working at ambient temp. 25 deg for refrigeration duty of - 20 deg. C Refrigeration Cycle should be studied at 12 specific point in the cycle

Ability to forecast State and Phase of Refrigerant at these 12 points and mastering P-h

Chart using these 12 points can allow true professionals to raise energy efficiency of

Refrigeration Systems and gain best of trouble shooting skills.

High Side of Cycle                   

Point Position                   State.        State.    Phase of Refrigerant
       
1. Inlet of Compressor               3               -18       Superheated Gas

2. Outlet of Compressor            25              80       Superheated Gas

3. Inlet to Condenser              25              70       Superheated Gas

4. 1/8 of Condenser               25               40       Saturated Vapour

5. ½ of Condenser                 25               40       45% Vapour +55% Liquid

6. 7/8 of Condenser               25               40       100% Saturated Liquid

7. Outlet of Condenser          25               33       Subcooled Liquid

8. Inlet of Metering device     25               32       Subcooled Liquid 

Low Side of Cycle                   

9. Outlet of MD                    3                -28       Liquid with Flash Gas

10. inlet of Evaporator        3                 -28       Liquid with Flash Gas


11. ½ of Evaporator            3                 -28       45% Liquid + 55% Vapour


12. Outlet of Evaporator     3                 -22       Superheated Gas

Please visit the site for the next post for the Part-2 of the Rules of Thumbs.

5 Wrongs At ACREX-2013

It is not only HVAC industry that should support energy conservation brigade but the trend in the whole world in any industry is such.There should be a strong movement in this direction.
 
Go Green - Environment friendly and the buzz word being "Dedicated to Eco Friendly Environment".
What rubbish !Ask ACREX-2013 organisers and visit the stalls of the companies you will find the vast difference between what is being propagated on the paper and what is the ground reality.
 
I was in ACREX-2013 exhibition held at Bombay Exhibition Center on 7th,8th & 9th in Mumbai.
I have attached the theme photo of the ACREX-2013 bill board that says "Dedicated to Eco Friendly Environment". The reality is far from the spirit of the theme.
 
The reasons are below:
 
1) I visited the stalls of the most big compressor manufacturers for the compressor requirement on "Natural Refrigerant" and couldn't find even a single manufacturer who could supply for the requirement.
 
2) We often talk of Renewable source of energy - Solar.The harsh reality is that most of the manufacturers are not ready to switch to this technology because of the captivity of their mind sets.
 
3) Companies are still using conventional HFC's and not ready to switch over.
 
4) No clear long term perspective from Small & Medium scale HVAC players.
 
5) No clear R&D guide lines on renewable source of energy use in present day environment.
 
I hear Australia has developed some of the solar energy concepts in HVAC and one of them I featured on my blog here and also at:
http://harshbardhanlive.wordpress.com/
where the energy being consumed is only 34 watts.
 
The need of the hour is to switch to more natural sources of energy and going green will be only possible when we change our mind sets and not merely on the bill boards as on ACREX-2013.

Feel free to comment on my post may be if your observation is different from mine I could change my outlook!