I believe any pressure developed in the impeller before exiting the periphery of the impeller is transient and does not contribute to the pressure produced at the discharge of the impeller in the volute due to conversion of kinetic energy, of the fluid exiting the impeller, to pressure. I have...
Never is a long time, and these four statements hardly add up to "never weld attachments to any SS pressure pipe of any thickness" IMO. All four are valid concerns, and may be more or less important for certain loads, thicknesses, pressures, and materials, but are also all valid concerns when...
I don't see an SIF for a reducer in B31.3 2014 but there is one in B31.1 2016 - note that flexibility factor is 1
(13) The equation applies only if the following conditions are met:
(a) Cone angle does not exceed 60 deg, and the reducer is concentric.
(b) The larger of D1/t1 and D2/t2 does...
@Snickster Thank you for the attached Kellogg method as this is most helpful. Are the Caesar stress results reflecting these localized stress results at points of restraint? I did see the WRC sub program in Caesar but would the geometry of the dummy leg welded to the elbows be reviewable with...
Looking further and as KevinZ indicated there is a stress concentration factor applied to the reducer (based on the connecting piping diameter and wall thickness). However, the SIF is based on the angle and also D2, t2- see attached.
I believe you would just analyze the connecting pipe at wall thickness of the connecting pipe at the connecting pipe wall thickness and at the location of the connections. There is no analysis of the reducer sloping section or stress concentration factor applied to the reducer as far as I can...
Caesar does have a WRC 107 sub-program. It has been a while since I used Caesar and the WRC 107 sub-program but I believe it can be used independent of a stress analysis. For instance, if you model a dummy leg and node at the connection of the dummy leg to the pipe then Caesar piping stress...
Here is the Kellogg method. It was the first method used and is still used today by design firms I worked for as the first check. If check passes the Kellogg method then no further analysis is required.
When designing piping systems you should check for local stresses at pipe supports, especially when using thin wall pipe such as Sch 10s. I had a project in which we used all Sch. 10s stainless steel and the local stresses at pipe supports were way above limits. The piping in this case rested...
I did my analysis on my own without having tried to do a differential equation set up like this in about 20 years so I don't know what you are talking about.
Well I was close. I forgot to include the weight force of the mass acting down, and I did not realize that you can reduce the restriction effect to a linear function R*Q = R*A*V and then use an approximate value of R as shown. I think my equation is still correct if I include the Mg factor...
You have to consider the entire work required to produce the refrigeration effect. Most of the work is typically the work of the compressor in a cooling system but includes all energy input such as evaporator fans, etc.
I do not agree with the analogy of using the same concept as a pump curve and system curve and finding the intersection. My understanding under that analogy the system curve drawn in red (or green) is the pressure loss in the pipe at given flow. So at 14.66 psia suction pressure (pressure in...
I don't think you need to include the pressure drop due to velocity increase from zero velocity prior to suction. If the graph was developed with open end at flange of ejector the curve already takes into account pressure drop due to velocity increase and friction losses between flange and...
More correctly what you have appears to be an "air ejector". I believe that the pressure you measured with flange blinded would result in measurement of the maximum suction pressure in the jet chamber during no flow in the suction, however there is an additional pressure drop when there is flow...
I posted my reply before I saw your post with the sketch of the exhauster. There does not appear to be any additional restriction at the inlet. It is not really a venturi but more like an eductor with different pressure/flow characteristics than a venturi, although I am not that familiar with...
I get about the same results as Katmar. If the total differential pressure is 1.46 psig (3 inHg) then at 600 lbs per hour (2.18 SCFS) the pressure drop will be equal to the available drop of 1.46 (3inHg) as you indicate between the entrance of the pipe and the end (top) of the pipe. This...
