AVERAGE AND LOCAL HEAT TRANSFER FOR CROSSFLOW OF LIQUID METAL IN A TUBE BANK

Journal Article · Thu Feb 01 00:00:00 EST 1962 · Dissertation Abstr.

OSTI ID:4837713

Rickard, C L

Local and average heat transfer coefficients were obtained for the flow of mercury normal to a staggered tube bank. The tube bank consisted of sixty 1/ 2-inch tubes, six wide and ten deep, arranged in an equilateral triangular array. Results are presented showing the effects of Reyn olds number, Prandtl number, wetting of the tube surfaces by the mercury, gas entrained in the liquid metal flow, tube location in the bank, and angular variation of tube surface temperature on the local and average heat transfer coefficients. Circumferential heat flow in the wall of t e tubes is shown to have an important bearing on calcul ion of true' local heat transfer coefficients, Analytical tudies of heat transfer to liquid metals in a tube bank ar presented which show the theory to be only in fair agree ent with the experimental results. Pressure drop result for both mercury and water flow through the tube bank are also given. The range of Reynolds numbers and Prandtl numbers covered in the mercury heat transfer tests was 20,000 to 200,000 and 0.0l4 to 0.022, respectively. A che on the accuracy of the experimental technique by measuring heat transfer rates to water flowing through the tube bank covered the Reynolds number range 8,000 to 20,0 0. The principal results obtained from the study are: the average and local heat transfer coefflcients for a tube with approxi-mately constant surface temperature located in e interior of the tube bank can be expressed by the equations Nu = 1.04 cos THETA !/sup 1/2 respectively; the average heat tra sfer coefficients at a given Reynolds number are higher- ior constant surface heat flux conditions than for constant rface temperature conditions; gas entrained in a liquid metal flow reduces heat transfer coefficients only under conditions of non-wetting and wetting or non-wetting of the heat transfer surfaces has no effect on the coefficients in the absence of gas entrainment and surface fouling; friction factors measured for the flow of mercury through the tube bank under non- wetting conditions are in general agreement with those for ordinary fluids and wetting or non-wetting of the tube surfaces in a tube bank has little if any effect on the pressure loss; and analytical solutions for heat transfer to liquid metals in a tube bank which are based on assumptions of molecular conduction and potential flow give Nusselt numbers which are 25% to 39% below the experimental results at a Peclet number of 4,000 and 8% to l8% below at a Peclet number of 600.

• Research Organization: Cornell Univ., Ithaca, N.Y.
• NSA Number: NSA-16-022310
• OSTI ID: 4837713
• Journal Information: Dissertation Abstr., Vol. Vol: 22; Other Information: Orig. Receipt Date: 31-DEC-62
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

ENGINEERING AND EQUIPMENT
ADHESION
CONFIGURATION
COUNTER CURRENT
DISTRIBUTION
EFFICIENCY
FLUID FLOW
FLUIDS
FRICTION
GASES
HEAT TRANSFER
HEATING
IMPREGNATION
IMPURITIES
LIQUID FLOW
LIQUID METAL COOLANT
LIQUID METALS
MATHEMATICS
MEASURED VALUES
MERCURY
MOLECULES
NUSSELT NUMBER
PECLET NUMBER
PERFORMANCE
PRANDTL NUMBER
PRESSURE
REYNOLDS NUMBER
SURFACE TENSION
SURFACES
TEMPERATURE
TESTING
TUBES
TURBULENCE
WATER
WETTING AGENTS