{ "cells": [ { "cell_type": "markdown", "metadata": {}, "source": [ "# 7.23 Flow Through Orifice Meters" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "A square edged orifice of 2\" diameter is installed in a 4\" schedule 40 pipe. A mercury manometer is connected between standard taps 1D upstream and 0.5D downstream.\n", "\n", "a) Find the theoretical calibration constant for the meter when 60 deg F water flows through the pipe in the fully turbulent region. \n", "\n", "b) Find the flow rate of 60 deg F water when the mercury deflection is 4.4\"" ] }, { "cell_type": "code", "execution_count": 1, "metadata": {}, "outputs": [], "source": [ "from fluids.units import *\n", "P1 = 2*u.bar # assumed\n", "T = 60*u.degF\n", "NPS, D_pipe, Do_pipe, t = nearest_pipe(NPS=4, schedule=40)\n", "mu = 1.1e-3*u.Pa*u.s # viscosity of water\n", "rho = 62.364*u.lb/u.ft**3 # density of water\n", "Do = 2*u.inch" ] }, { "cell_type": "code", "execution_count": 2, "metadata": {}, "outputs": [ { "data": { "text/html": [ "105.73900650508152 gallon/minute" ], "text/latex": [ "$105.73900650508152\\ \\frac{\\mathrm{gallon}}{\\mathrm{minute}}$" ], "text/plain": [ "105.73900650508152 " ] }, "execution_count": 2, "metadata": {}, "output_type": "execute_result" } ], "source": [ "# b)\n", "dP = (4.4*u.inch_Hg - 4.4*u.inch_H2O_60F)\n", "P2 = P1 - dP\n", "m = differential_pressure_meter_solver(D=D_pipe, rho=rho, mu=mu, k=1e20, D2=Do, P1=P1, P2=P2, \n", " meter_type='ISO 5167 orifice', taps='D and D/2')\n", "Q = (m/rho).to(u.gal/u.min)\n", "Q" ] }, { "cell_type": "code", "execution_count": 3, "metadata": {}, "outputs": [ { "data": { "text/plain": [ "(0.6067029339232126 ,\n", " 0.6260667537160854 )" ] }, "execution_count": 3, "metadata": {}, "output_type": "execute_result" } ], "source": [ "# a)\n", "C, _ = differential_pressure_meter_C_epsilon(D=D_pipe, rho=rho, m=m, mu=mu, k=1e20, D2=Do, P1=P1, P2=P2,\n", " meter_type='ISO 5167 orifice', taps='D and D/2')\n", "C, flow_coefficient(D_pipe, Do, C)" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "Crane TP 410 reports a flow coefficient of 0.625 and a flow rate of 106 gal/min, indicating the problem benefited from the iteration little." ] } ], "metadata": { "language_info": { "name": "python" } }, "nbformat": 4, "nbformat_minor": 1 }