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I have been modeling a Building and I would like to know the considerations that I have to take account regard to the ceiling void 0.5m high. I am Considering this ceiling void as a space. The reason for that is because from about 0.2 m of high, we start to observe convection effects, and I think, Considering that ceiling only as air gap (convection effects are not being taken into account), I am not modeling that appropriately. So, which of two considerations above is the better one? Thanks.

I would like to know if Open Studio provides all the tools necessary to run the simulation of a model aiming to certify this model in the LEED certification. To be more clear, what I want to know is if there is any missing tool in the Opestudio which will not allow me to simulate my model and produce the required data to certify my building in the LEED certification.

I have been modeling a building to submit it to LEED certification and I have some issues Regarding to how to set Correctly fan parameters for the baseline model . I am aware que ASHRAE 90.1 provides a table regarding to BASELINE FAN MOTOR POWER, but I am not find the relation between them and the values ​​found in OpenStudio to configurate the fans. In OpenStudio we have as a fan input The Following items:

FAN EFFICIENCY PRESSURE RISE MAXIMUM FLOW RATE MOTOR EFFICIENCY MOTOR IN AIRSTREM FRACTION

I would like to know which one of them I have to set, and where I can get the values ​​to set them correctly. I know, for instance, that TRACE 700 when is dealing with a BASELINE model of its own calculations. I do not need to set such parameters in there, only for the proposed model.

After run a simulation on OpenStudio, it is possible to have acess to the entire report of the model. However, to submit the reports to LEED process of certification, we need to take parts of this reports. Anybody Knows how to ask for those reports in separated, for instance: A file with the ANNUAL UTILITY PERFOMANCE SUMMARY; another file with INPUT VERIFICATION AND RESULTS SUMMARY, I mean, the big report broked into small ones.

I am modeling a building to submit to LEED certification and I have a concern regard to the baseline HVAC system and the increment of 15% applied to the Equipment Capacity.

First, regarding to the baseline HVAC system, I am using two chillers and fan coils to met the thermal load of the proposed model. Considering that my building has three floors, I choose the system 4, as presented in the picture below.

To represent this system in EnergyPlus, I set the following system in OpenStudio (Packaged Rooftop Heat Pump).

Is it the right representation of the system 4 (appendix G- Table G.3.1.1B)?

Second, Should I Set the 15 % for both models, baseline and proposed model, or only apply this coeficient for the baseline model.

Is there a measure to add a real VRF system in Open Studio like it is possible to do with Chillers?

I would like to know an output variable to analyze the behavior of a chiller along the project day and also the thermal load which this chiller is responsible to attend (basically I want the thermal load of the building).

I know that EnergyPlus provides the nominal capacity of the chiller. The problem is that, they probably are doing some considerations before print this value in the results. This is why I am asking for an output variable which allow me understand how my chiller is really working during a piriod of time.

I Have Been working with simulation of models and I have some concerns about the REFERENCE INPUT of the equipaments . To explain my concerns I will take a chiller as an example: So , I have imported a chiller from the e+ library to my model and some of the inputs of my chiller are already set.

For instance : REFERENCE COP : 3:05 REFERENCE LEAVING CHILLED WATER TEMPERATURE : 6.67 ° C ENTERING refrence CONDESER FLUID TEMPERATURE : 35 ° C

For the real project I already have the Chilled selected and the datasheet of this equipments selected for my project conditions . REFERENCE LEAVING CHILLED WATER TEMPERATURE : 7 ° C Refrence ENTERING CONDESER FLUID TEMPERATURE : 34 ° C

My question is : Do I have to change this for the inputs the ones I have in the data sheet , or should I leave then and the program will take the chiller coefficients, that define the perfomance curves of this equipament, and do the calculations with the plant input que I had set?

I read the INPUTOUTPUTREFERENCE, but there they say that inputs are reference inputs and do not say if I should change it.

Thank you very much guys.

If I add the Cooling Coil Total Cooling Rate of each coil of my secondary plant, then I end up with a value that is smaller than the Plant Supply Side Cooling Demand Rate. For me it must be approximately the same value. The Following picture shows my secondary plant . Circulated in yellow the coil that I mentioned (there is one for each climatized room) .

I am using in my HVAC model the components circulated in yellow, in the follow picture.

My question is if these element represents a water heat exchanger, responsible for exchange heat with air that will be after insufflated inside the rooms. If yes, what is the usual heat exchange configuration adopted in this solution, I mean, a counterflow or a crossflow.

Hi,

I´ve been working in a HVAC system and I am facing a problem regarding to the fans that I had applied to my model. The fan is a constant volume fan. I made a schedule in order to turn the fan off during the weekends and between time period of 7:00pm and 7:00am during week. Then I associated this schedule to each fan. The result shows no reduction in the energy consumption if compared with the case in which the fans are kept turn on 24 hours per day, and every day of the week. It seems that the schedule made by me it is not being working. A bring some pictures here to show in details how I am dealing with it. My conclusion is based on the fan consumption which remains the same, even when my schedule is applied and in the zone mechanical ventilation, which shows that this fan is working continuously, without interruption (last picture).

Thanks!!!

Hi,

In order to Achieve such goal , I use to set the HVAC system and thermostat the temperature to 23 ° C. So , I run the simulation and in the end I plot the graph for each PMV Evaluated zone And Then , I simply check if the PMV is lower than 0.5 and greater than -0.5 . If it did not happen , I change the set point temperature of the thermostat According to the PMV values ​​shown in graph Until the PMV value lies between the range of 0.5 to 0.5 . I was checking at Energyplus references and I saw two topics that I judge que be important in order to have as an output the ideal temperature to set my system, based on the PMV analysis : " Zone Control : Thermostat : Thermalconfort " and " ThermostatSetpoint : ThermalConforft : Fanger : DualSetpoint " . The problem is: I do not know how to apply them in my model and not need checking zone by zone and also having to change the the thermostat temperature when the PMV of the zone is out of the limits of the acceptable range ( between - 0.5 and 0.5).

Thanks guys.

@obuchely, set the two plants loops: one with the chiller and other with the cooling tower. Then, with the cooling tower loop opened, go in the right tab, choose the option MY MODEL and drag the Chiller that you have in there to the cooling tower loop. Hope it´ll work properly.