This lesson covers the use of multi-hole probes in fluid mechanics, focusing on the differences between 3-hole and 4-hole probes. The lesson explains the additional feature of 4-hole probes that allows for the measurement of an extra flow parameter, which cannot be measured using a 3-hole probe. The lesson also discusses the pressure measurement using these probes and their importance in measuring flow parameters in a turbo machine. The lesson further explains the types of probes, their placement in the flow field, and the problems associated with pressure measurement using these probes. The lesson concludes with a detailed explanation of the construction and operational principle of 4-hole probes.
00:41 - Difference between 3-hole and 4-hole probes
01:37 - Importance of multi-hole probes in measuring flow parameters
02:48 - Problems with pressure measurement using probes
06:16 - Construction of 4-hole probes
19:45 - Operational principle of 4-hole probes
- Multi-hole probes, specifically 3-hole and 4-hole probes, are essential tools in fluid mechanics for measuring flow parameters.
- 4-hole probes have an additional feature that allows for the measurement of an extra flow parameter, which cannot be measured using a 3-hole probe.
- The probes are placed in the flow field with careful consideration of their orientation and the uniformity and steadiness of the flow.
- The construction of 4-hole probes involves drilling holes radially and extending them vertically for connectors to the pressure leads.
- The operational principle of 4-hole probes involves yawing the probes until the pressure at certain orifices becomes equal.