A launching rocket vehicle technology development is cooling

A
notable provocative interdisciplinary area of research in launching rocket
vehicle technology development is cooling of liquid rocket engine (LRE). During
the process of rocket launching vehicle both fuel and oxidizer are burnt in LRE
combustion chamber as a consequence, hot gases are released from a nozzle to
gain the required thrust. As a consequence, both the nozzle and chamber under
goes high temperature. In order to safeguard the nozzle and chamber of rocket
engine they need to be cooled. Numerous ways of cooling strategies are implemented
to safeguard the nozzle and chamber walls. Thermo physical properties of the
fluid and flow velocity are the key factors which controls the cooling
performance of the nozzle and the chamber walls. Enhance in pressure drop
results in the growth of fluid velocity along with requisite pumping power.
Kerosene the fuel, is being used as regenerative coolant in the case of
semi-cryogenic engine. During the regenerative passage the temperature of the
kerosene should not reach coking limits as thermal conductivity of kerosene is
low. In this regard the thermo physical properties of the kerosene can be
improved which can enhance the heat transfer capacity of kerosene which
influences the exploration of cooling system for semi-cryogenic engine.

The idea of improving heat transfer
performance of fluids with the inclusion of solid particles was first
introduced by Maxwell 2. Suspensions involving milli or microsized particles
create problems, such as sedimentation, clogging of channels, high pressure
drop and severe erosion of system boundaries, to overcome these problems Choi
3 used ultra fine nanometered sized particles (diameter less than 50nm) like
Aluminium, Copper, Silicon, Silver and Titanium or their Oxides dispersed in a
base fluid such as water, ethylene, glycol, toluene and oil. Nanofluids is the term first coined by Choi 2. Nanofluids
have several cooling applications which includes nuclear reactors, vehicle, transformer,
silicon mirror and electronics cooling. In addition these nanofluids can also employed
in several areas such as auto-mobile engines, lubricants, heat exchangers,
micro channel heat sinks, welding equipment, micro-electro-mechanical system and
Wang et al 1. The natural convective flow of a
nanofluid over a convectively heated vertical plate was investigated by Aziz
and khan 4. The natural convection flow past an isothermal horizontal plate
in a porous medium saturated by a nanofluid was studied by Gorla and Chamka 8.
Free convection boundary layer flow past a vertical plate was examined by Kuznetsov
and Nield 9. Turkyilmazoglu 11 examined the heat transfer in transient flow
of some nanofluids over a vertical flat plate. The natural convection flow of a
water-Al2O3 nanofluid was developed by Congedo et al. 16.

 

In
engineering and industrial systems buoyancy-driven flow and heat transfer in vertical
geometries have several important applications for instance solar-collectors, electrical
and microelectronic equipments containers, petroleum reservoirs, geothermal
engineering, thermal buildings insulation, etc. To discuss the importance of
buoyancy force on fluid flow and heat transfer under various physical
conditions, many studies have been published. The combined effect of buoyancy
force and Navier slip on magneto-hydrodynamic flow of a nanofluid over a
convectively heated vertical porous plate was numerically investigated by
Mutuku-Njane and Makinde 18.The forced convective heat transfer due to flow
of  Al2O3–water nanofluid
through a pipe filled with a metal foam was studied experimentally by Nazari et
al.19.

During
the motion of fluid particles, viscosity of the fluid converts some kinetic
energy into thermal energy. Since this process is irreversible and caused due
to viscosity, so this is called viscous dissipation. Viscous dissipation is quite
often a negligible effect in
macro scale systems, in laminar flow in particular, except for very viscous
liquids at comparatively high velocities, but it’s contribution might
become important when the fluid viscosity is very high. It changes the
temperature distributions by playing a role like an energy source, which leads
to affected heat transfer rates. The effect of viscous and joules dissipation
on MHD flow past a streaching poroussurface embedded  in a porous medium for ordinary fluid was studied
by Anjali devi and Ganga 21 .The effect of thermal radiation and viscous
dissipation on boundary layer flow of nanofluids over a moving flat plate were
investigated by Motsumi and Makinde 22.The flow of MHD viscous fluid in porous medium through a moving vertical
plate was inspected by singh23. The stagnation point flow of micropolar fluid
through porous medium and heat transfer with viscous dissipation was discussed
by Kishan et al 24