Recent content by dpolet

If this example require to use Maximum Normal stress theory, should the compressive normal stress be directly used into eq50.4? or should the principal stress be calculated and used into eq50.4? Thanks.

CRNewsom,you are correct. I mixed psia and psig. Thank you.

NCEES 2008 AM #138 use 970btu/lbm. However, I found at 14.7psia, the water Hfg=1060 btu/lbm. They have different btu/lbm, did I miss anything? Thanks.

If a room was kept at condition1(enthalpy is H1), and the outdoor air condition was given(enthalpy is H2), to calculate the coil load of outdoor air ventilation (CFM was given), should we use the equation of: Q=4.5*CFM*(H1-H2). Thanks.

I understand. Thanks a lot.

These chart are clear. Thank you.

CRNewsom,could you send to me the printable P-H chart? My email is dpolet72 at yahoo.com. Thanks.

bknewto7, I am still a little confused about this when I came across 2001 ncees sample exam T&F #507. I understand the ncees solution method. However, i am not sure how to apply this equation (sensible load (BTU/Hr) = 1.08 * CFM * Delta T) on #507.or the equation should not be used on this...

I will take T&F afternoon. When calculate fluid loss through a valve, will the equiv.length (ft) be listed in the exam (AM+PM)? I did see this in 2008 ncees sample exam, but I am not sure if this is the general rule. I have another question about the R134a P-H chart. Will the ncees give...

I understand now. Thank you very much.

bknewto7, thanks for the response. If the room sensible heat load is 0btu/hr (but the latent load is not zero), the air flow will be 0 CFM. However, if there is no air flow, how the latent load will be removed?

Air flowing at a rate of 3600cfm, and initially at 80F db/67 wb, is passing through a spray of water solution, which has stabilized at 100F. assume a 0.05 bypass factor for spray chamber. What is the flow of dry air at initial conditions (lb/hr)? I am a little confused. How to solve this...

A room has the following: sensible heat gain = 90,000btu/hr latent heat gain = 40,000 btu/hr supply to room = 60F The room is kept at 82 db. When calculate air flow to the room, why only the sensible heat gain is used? Which page of MERM focus on this information? Thanks in advance.

Here is the detailed data Air expands isentropically from point 1 to point 2 P1=200 psia T1=1960R P2=50 psia T2=? using the equation of isentropical process (P2/P1)=(T2/T1)^(k/k-1) k=1.4 for air. T2 can be calculated to 1319R Did I do anything wrong on this calculation? Thank you.

I found App24F and direct isentropical equation will generate different results. Which one will be used? For example, Linderburg 500 practice problem 29-1. I get result of 1319R using equation. the solution is 1375R using air table. Did I do anything wrong? Thanks.