Impact of Jet
OBJECTIVES
The objectives of the experiment are:
1. To demonstrate pump performance when connected in series and parallel
2. To show shut off point of pump in series and parallel
ABSTRACT / INTRODUCTION Pump is a general term for any fluid machine; used to transfer and add energy to fluid in a system, either at the same level or to a new height. There are some fundamental parameters used to determine the performance of a pump. The mass flow rate of fluid is the obvious primary pump performance parameter and for incompressible flow, it is more common to use volume flow rate rather than mass flow rate. The performance of a pump is characterized by its net head, H. In selecting a pump for a given situation, we have a variety of pumps to choose among. The manufacturers provide the pump performance information such as the pump performance curves. The engineer’s task is to the pump or pumps that best fits in with the system characteristics. One of the considerations in fulfilling a system characteristic is whether to combine a pump in one system or not. The combination may be in parallel or series. When pumps are operated in series, the combined net head is simply the sum of the net heads of each pump at a given volume flow rate.
Combined net head for n pumps in series: Hcombined = ∑Hi
While if two or more identical or similar pumps are operated in parallel, their individual volume flow rates rather than their net heads are summed.
Combined capacity for n pumps in parallel: Vcombined = ∑Vi
The flow rate depends on the height to which the fluid is pumped, and the relationship between “head” and flow rate is called the “pump characteristic curve.” Often in engineering applications a single pump cannot deliver the flow rate or head necessary for a particular need, and two or more pumps can be combined in series to increase the height to which the fluid can be pumped, or in parallel to increase the flow rate.
The objectives of the experiment are:
1. To demonstrate pump performance when connected in series and parallel
2. To show shut off point of pump in series and parallel
ABSTRACT / INTRODUCTION Pump is a general term for any fluid machine; used to transfer and add energy to fluid in a system, either at the same level or to a new height. There are some fundamental parameters used to determine the performance of a pump. The mass flow rate of fluid is the obvious primary pump performance parameter and for incompressible flow, it is more common to use volume flow rate rather than mass flow rate. The performance of a pump is characterized by its net head, H. In selecting a pump for a given situation, we have a variety of pumps to choose among. The manufacturers provide the pump performance information such as the pump performance curves. The engineer’s task is to the pump or pumps that best fits in with the system characteristics. One of the considerations in fulfilling a system characteristic is whether to combine a pump in one system or not. The combination may be in parallel or series. When pumps are operated in series, the combined net head is simply the sum of the net heads of each pump at a given volume flow rate.
Combined net head for n pumps in series: Hcombined = ∑Hi
While if two or more identical or similar pumps are operated in parallel, their individual volume flow rates rather than their net heads are summed.
Combined capacity for n pumps in parallel: Vcombined = ∑Vi
The flow rate depends on the height to which the fluid is pumped, and the relationship between “head” and flow rate is called the “pump characteristic curve.” Often in engineering applications a single pump cannot deliver the flow rate or head necessary for a particular need, and two or more pumps can be combined in series to increase the height to which the fluid can be pumped, or in parallel to increase the flow rate.
References: 1. Yunus A.Cengel and John M. Cimbala, Fluid Mechanics: Fundamentals and Application, McGraw-Hill, pg.764-779, 2006. 2. Syed Noh Syed Abu Bakar Al-Saggof and Sanisah Saharin, Fluid Mechanics Laboratory Guidelines for Aerospace Engineering Laboratory 1(MEC 2700), January 2008 3