Thermal insulation is widely used in thermal power plants, gas turbines, steam carrying pipes, petrochemical processing plants etc., for improving energy efficiency and protecting the working personnel. The insulation material properties, like thermal conductivity, ageing, weight etc., determine its acceptability for a particular installation unit. It is observed that the thermal conductivity of the insulation material used and the effective thermal conductivity obtained after fixing the insulation on the target differs significantly. Although extensive literature is available on the effective thermal conductivity of building insulation, experimental studies on high-temperature insulation as found in energy systems are scarce. In the present work, the numerical design of an experimental setup to study the effective thermal conductivity of thermal insulation at high temperatures (>373K) when applied on a curved hot surface is carried out. A setup is designed using numerical simulations. The selected design setup is fabricated and experimentally investigated. The heat losses from different sides are experimentally evaluated and compared with numerical results. A reasonable agreement is observed between the two data. It is observed that the maximum heat loss happens through non-target surfaces (i.e. surfaces other than the top curved surface) when the heater is attached to the inside of the top cover. Whereas, maximum heat transfer through the top curved surface is observed when the heater is placed on the insulation.