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When Physics Gets Puzzling

The Energy Enigma That’s Got Scientists Scratching Their Heads

What happens when a simple invention challenges one of physics’ most famous equations? Spoiler alert: Einstein might need to make room at the table.

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A great asset to DDSB

David has been our primary Controls Contractor for last 25 years. We are always surprised that even today he comes up with new and innovative designs.

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Recent Videos

Bourdon Tube Investigation

Industry experts contacted indicated that the volume of a Bourdon tube does not change while flexing or they had no data on this consideration. If the industry consensus is true, work output can exceed work input (Wout ˃ Win) as per an APS experiment.

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Questions?

HVAC systems that mix fresh air and building return air to varying quantities for cooling purposes often have control logic comparing the total heat content of the outdoor air to the total heat content of the return air. (Total heat content in air is called enthalpy.) 

Typical logic reverts the fresh air dampers back to the code ventilation level when the enthalpy in the outdoor air exceeds that in the return air.

The rest time of the HVAC refrigeration as well as the run time are factors in determining the total energy cost of mechanical cooling for the HVAC system.

If the outdoor air temperature is lower than the return air temperature when the refrigeration is off altering the HVAC dampers to full fresh air would extend the rest time for the refrigeration because the HVAC system would be providing cooler air to the occupied space.

Limitations on the RH level may be required in the designer’s logic.