Concept Selection: An Improved Clog Resistance Testing Methodology for Wastewater Pump Using Pugh Decision Model

Abstract

Decision making is a systematic process and is an integral part of
design function. This paper discusses the application of Pugh’s
decision matrices in concept selection within wastewater pump clog
resistance testing methodology. Two individual concepts to test clog
resistance testing in advanced wastewater pumps have been
developed. A set of decision criteria were established and concept
evaluation and selection have been carried out using Pugh’s
decision-making model. Combination of both concepts was used as
datum while individual concepts were simultaneously compared
against it and the outcome weighted. The recirculation concept
showed a weighted total of 11 over the lifting device concept with 3.
The datum was rotated and the recirculation concept showed a
weighted total of 46 over the combination concept with 11. The
recirculation concept has been selected and a standard two pump
system with variable speed drive was further developed under this
concept to assess upper volume clogging in wastewater pumps.
Experiments were designed for this methodology and validation
tests were carried out using Flygt N3085SH (standard and upgraded
version) and N3069SH pumps with a combination of parts from the
small product range. The results achieved with this methodology
validate its efficiency and show that Pugh’s matrices if employed
correctly can be a tool in decision making in engineering design