On The Road Again

To quote one of my favorite musicians, Willie Nelson, we are going ..."On the road again, just can't wait to get on the road again..." this time to Las Vegas for the 2017 AHR Expo. 

The Mestex division of Mestek will be sharing booth space with our sister companies in booth C1525 in the Las Vegas Convention Center.  Some people are predicting a record turnout of attendees and we expect a busy few days.

This year, Mestex will be using some new (for us) graphical display technology from the Mestek Technology group to help explain some of our newer product offerings.  Our division companies; Applied Air, Aztec, Alton, LJ Wing, Temprite, and King provide solutions to temperature, pressure, airflow, and filtration problems that can be hard to explain using a static piece of equipment.  This graphical display technology will allow us to "walk you in" to three of our products and highlight how certain elements of the products can be used to address your building or process issues.

In addition to these graphics the Mestex people in the booth can explain how our in house CFD analysis services can help optimize a solution.  Projects ranging from large e-commerce warehouses and distribution centers to data centers to "indoor agriculture" grow rooms can be very difficult to design due to high internal thermal loads, humidity levels, stratification, or pressure gradients and CFD allows Mestex to thoroughly analyze and sort out possible solutions.

So come on by the booth and, at least, say "hi".  We would love to discuss how we might help solve your application problems.

Relative Humidity – It’s all relative

A Guest Article by Jim Jagers

The other day I was conducting a training class, and we were discussing evaporative cooling. Someone said they didn’t think evaporative cooling would work very well in their area because the summer temperatures were 90°F plus with 90% RH. If you were to look at many psychrometric charts, you’d see this point is, dare I say it, “off the chart”. To get a feel for this consider a steam room has general temperature of 104°F and 100%RH. At 90°F with 90% RH the heat index is 122°F. It’s doubtful the temperature and humidity are as bad at the same time as he imagined.

People generally associate high temperatures with high humidity percentages. It’s more likely that high temperatures will be associated with lower humidity percentages. At 80°F and 41%RH the heat index is 80°F. 80 degrees feels like 80 degrees. At this point there is approximately 0.009 pounds of moisture per pound of dry air in the atmosphere. If the moisture content remained constant and the air warmed to say 90°F, the relative humidity would actually drop to about 30%. Conversely, if the moisture content remained constant and the temperature dropped to 70°F, the relative humidity would increase to about 57%. This is because cooler air can hold less moisture than warmer air, and relative humidity is the ratio of the moisture in the air compared to the amount of moisture the air (at a specific temperature) can hold expressed as a percentage.

People usually think of their air conditioner as providing cool dry air in the summer, and it does because it does both sensible and latent cooling. Sensible cooling lowers the temperature we sense, and latent cooling removes the moisture. The air entering the coil may be 78°F and have 0.0101lbs of moisture per pound of dry air. The coil temperature may be 45°F and thus the leaving air may be 60°F (It won’t be 45°F because the water in the air is absorbing some of the cold). At this point the leaving air may have a moisture content of 0.0062lbs per pound of dry air. This is a significant reduction in moisture, and it is evidenced you water dripping from the evaporator coil. The leaving air is much dryer than the entering air.

However, in relative terms the air coming off the evaporator coil in the air handler has a relative humidity of 100% or close to it. Remember, cool air can’t hold as much water as warm air. When the air entering the coil, contacts the cold fins it cools rapidly. Condensation occurs when air can’t hold the moisture it contains. At this point the air is fully saturated meaning its relative humidity is 100%.

The point to this brief essay is, as I said at the start, relative humidity is all relative - to the moisture in the air and the air temperature. Warm air isn’t necessarily humid; cool air isn’t necessarily dry, relatively speaking.

Indirect Evaporative Cooling Research Project Launched

Aztec ASC 3-D Model for CFD Research

ASME Paper Documents CFD Modeling of Aztec IDEC System

The 2013 ASME “International Technical Conference and Exhibition on Packaging and Integration of Electronic and Photonic Microsystems”, aka ”InterPACK 2013” is just concluding in San Francisco.  As the conference title implies there are papers and presentations from all over the planet that are focused on research into improving electronics, computers, and data centers.

One of those papers presents results from an on-going research project that Mestex has started with the College of Engineering at the University of Texas at Arlington.  This research project will likely go on for a couple of years and this paper presents some of the first findings that are being used to establish a “baseline” for the rest of the research.

The paper is listed in the proceedings as “InterPACK2013-73302”.  The human-readable title is “CFD MODELING OF INDIRECT/DIRECT EVAPORATIVE COOLING UNIT FOR MODULAR DATA CENTER APPLICATIONS” and the paper covers exactly what the title suggests.  The IDEC product that the paper covers is the Aztec ASC-20 and the goal is to establish that the factory data that we present in our literature can be validated against a detailed CFD model of the product.

By modeling the Aztec ASC-20 components and creating the 3-D CFD model using factory dimensional drawings the researcher was able to confirm that the published factory data is accurate and the ASC-20 will perform as predicted based upon the operating parameters.  This important result can be used to further our research into optimizing the performance of evaporative cooling and fresh air cooling solutions for mission critical/data center applications.  A full scale modular data center mock up is being installed at the Mestex facility and additional documentation and validation of the performance will be conducted over the next several months.  The CFD baseline model will be used to simulate filter performance and airflow changes prior to making the physical changes to the research module.

The Aztec, and Alton DEC, evaporative cooling products have been used in the industrial and large commercial market since 1946.  Over those 66 years the products have been refined and optimized.  This research project will take the product lines to another level of thermal performance, water use optimization, and control software optimization with a specific emphasis on the needs of the mission critical market.

Mestex Hosts Independent Representatives at ASHRAE

Mestex Representatives Attend ASHRAE

With the annual ASHRAE/AHR meetings and exhibits in Dallas for the first time in 6 years, Mestex took advantage of the opportunity to host over 100 independent Mestex reps at the Mestex facility. We were also joined by a number of Mestek corporate employees including Stewart Reed, Mestek CEO.




Mestex DDC Dashboard

Test Area Demonstration

The reps were provided with guided factory tours that included presentations at four key areas in the plant...the gas-fired products test area, the hydronic products test area, the "Mestex Mall" show unit area, and the top secret Mestex R&D area. In addition to highlighting the extensive final test processes that every Mestex product endures the tour also highlighted the latest version of the Mestex DDC control system with full web-enabled interface and user "information dashboard".



"Dallas" Based Theme

Following the tours the reps gathered in the stage area that was set up in the plant for formal presentations on new software technologies that Mestex is introducing in 2013, a more detailed look at the DDC "dashboard", and a glimpse into a huge new sales opportunity. The presentations wrapped up with the introduction of the 2013 Sales Incentive program. The overall formal presentations were introduced by Mestex personnel who played the parts of characters from the TV series "Dallas".

Mestek Booth at ASHRAE/AHR Show

Over the following three days, Mestex personnel hosted a number of engineer and customer visits to the facility and also attended the ASHRAE/AHR show as part of the large Mestek contingent.