Venturimeter installation – effect of inclination on reading When a venturimeter is installed in an inclined position, then for a given discharge the instrument will indicate __________ differential head reading (between its pressure taps):

Introduction:
Venturimeters measure flow rate from the pressure drop between an upstream section and a throat. This question probes whether instrument inclination alters the indicated differential for the same flow.

Given Data / Assumptions:

• Same two tap locations relative to the converging section and throat, regardless of pipe orientation.
• Elevation difference between taps is properly accounted for in static head (as usual in Bernoulli).
• Flow, fluid, and temperature are unchanged.

Concept / Approach:
The venturimeter reading corresponds to the pressure difference arising from velocity change, not from instrument orientation. Bernoulli’s equation includes elevation head z; when taps move together with the pipe, their relative elevation difference remains the same. Thus, for the same Q, the pressure differential (and manometer reading) is unchanged.

Step-by-Step Solution:
1) Apply Bernoulli between the upstream tap and the throat.2) For identical geometry, Δz between taps is the same whether the meter is horizontal or inclined along its axis.3) The velocity head difference for a fixed Q is the same.4) Therefore the measured Δp (converted to differential head) is the same.

Verification / Alternative check:
Manufacturers’ calibration curves specify discharge vs differential head independent of installation angle, provided taps are at the specified axial positions and manometer connections are correct.

Why Other Options Are Wrong:

• More or less: would imply geometry-dependent Δz changed, which it does not for the same tap spacing along the meter.
• Indeterminate or zero: contradicts standard venturimeter principles.

Common Pitfalls:
Confusing “inclined manometers” (used to increase reading sensitivity) with an inclined venturimeter body; these are different ideas.

Final Answer:
the same